Merge pull request #48535 from groud/tiles_squashed

TileSet and TileMap rework (squashed)

13 files changed, 7953 insertions, 0 deletions

diff --git a/editor/plugins/tiles/SCsub b/editor/plugins/tiles/SCsub
new file mode 100644
index 0000000000..359d04e5df
--- /dev/null
+++ b/editor/plugins/tiles/SCsub
@@ -0,0 +1,5 @@
+#!/usr/bin/env python
+
+Import("env")
+
+env.add_source_files(env.editor_sources, "*.cpp")
diff --git a/editor/plugins/tiles/tile_atlas_view.cpp b/editor/plugins/tiles/tile_atlas_view.cpp
new file mode 100644
index 0000000000..4de2f962bc
--- /dev/null
+++ b/editor/plugins/tiles/tile_atlas_view.cpp
@@ -0,0 +1,649 @@
+/*************************************************************************/
+/*  tile_atlas_view.cpp                                                  */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "tile_atlas_view.h"
+
+#include "core/input/input.h"
+#include "core/os/keyboard.h"
+#include "scene/gui/box_container.h"
+#include "scene/gui/center_container.h"
+#include "scene/gui/label.h"
+#include "scene/gui/panel.h"
+#include "scene/gui/texture_rect.h"
+
+#include "editor/editor_scale.h"
+
+void TileAtlasView::_gui_input(const Ref<InputEvent> &p_event) {
+	bool ctrl = Input::get_singleton()->is_key_pressed(KEY_CONTROL);
+
+	Ref<InputEventMouseButton> b = p_event;
+	if (b.is_valid()) {
+		if (ctrl && b->is_pressed() && b->get_button_index() == MOUSE_BUTTON_WHEEL_DOWN) {
+			// Zoom out
+			zoom_widget->set_zoom_by_increments(-2);
+			emit_signal("transform_changed", zoom_widget->get_zoom(), Vector2(scroll_container->get_h_scroll(), scroll_container->get_v_scroll()));
+			_update_zoom(zoom_widget->get_zoom(), true);
+			accept_event();
+		}
+
+		if (ctrl && b->is_pressed() && b->get_button_index() == MOUSE_BUTTON_WHEEL_UP) {
+			// Zoom in
+			zoom_widget->set_zoom_by_increments(2);
+			emit_signal("transform_changed", zoom_widget->get_zoom(), Vector2(scroll_container->get_h_scroll(), scroll_container->get_v_scroll()));
+			_update_zoom(zoom_widget->get_zoom(), true);
+			accept_event();
+		}
+	}
+}
+
+Size2i TileAtlasView::_compute_base_tiles_control_size() {
+	// Update the texture.
+	Vector2i size;
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+	if (texture.is_valid()) {
+		size = texture->get_size();
+	}
+
+	// Extend the size to all existing tiles.
+	Size2i grid_size = tile_set_atlas_source->get_atlas_grid_size();
+	for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+		Vector2i tile_id = tile_set_atlas_source->get_tile_id(i);
+		grid_size = grid_size.max(tile_id + Vector2i(1, 1));
+	}
+	size = size.max(grid_size * (tile_set_atlas_source->get_texture_region_size() + tile_set_atlas_source->get_separation()) + tile_set_atlas_source->get_margins());
+
+	return size;
+}
+
+Size2i TileAtlasView::_compute_alternative_tiles_control_size() {
+	Vector2i size;
+	for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+		Vector2i tile_id = tile_set_atlas_source->get_tile_id(i);
+		int alternatives_count = tile_set_atlas_source->get_alternative_tiles_count(tile_id);
+		Vector2i line_size;
+		Size2i texture_region_size = tile_set_atlas_source->get_tile_texture_region(tile_id).size;
+		for (int j = 1; j < alternatives_count; j++) {
+			int alternative_id = tile_set_atlas_source->get_alternative_tile_id(tile_id, j);
+			bool transposed = Object::cast_to<TileData>(tile_set_atlas_source->get_tile_data(tile_id, alternative_id))->get_transpose();
+			line_size.x += transposed ? texture_region_size.y : texture_region_size.x;
+			line_size.y = MAX(line_size.y, transposed ? texture_region_size.x : texture_region_size.y);
+		}
+		size.x = MAX(size.x, line_size.x);
+		size.y += line_size.y;
+	}
+
+	return size;
+}
+
+void TileAtlasView::_update_zoom(float p_zoom, bool p_zoom_on_mouse_pos, Vector2i p_scroll) {
+	// Compute the minimum sizes.
+	Size2i base_tiles_control_size = _compute_base_tiles_control_size();
+	base_tiles_root_control->set_custom_minimum_size(Vector2(base_tiles_control_size) * p_zoom);
+
+	Size2i alternative_tiles_control_size = _compute_alternative_tiles_control_size();
+	alternative_tiles_root_control->set_custom_minimum_size(Vector2(alternative_tiles_control_size) * p_zoom);
+
+	// Set the texture for the base tiles.
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+
+	// Set the scales.
+	if (base_tiles_control_size.x > 0 && base_tiles_control_size.y > 0) {
+		base_tiles_drawing_root->set_scale(Vector2(p_zoom, p_zoom));
+	} else {
+		base_tiles_drawing_root->set_scale(Vector2(1, 1));
+	}
+	if (alternative_tiles_control_size.x > 0 && alternative_tiles_control_size.y > 0) {
+		alternative_tiles_drawing_root->set_scale(Vector2(p_zoom, p_zoom));
+	} else {
+		alternative_tiles_drawing_root->set_scale(Vector2(1, 1));
+	}
+
+	// Update the margin container's margins.
+	const char *constants[] = { "margin_left", "margin_top", "margin_right", "margin_bottom" };
+	for (int i = 0; i < 4; i++) {
+		margin_container->add_theme_constant_override(constants[i], margin_container_paddings[i] * p_zoom);
+	}
+
+	// Update the backgrounds.
+	background_left->update();
+	background_right->update();
+
+	if (p_scroll != Vector2i(-1, -1)) {
+		scroll_container->set_h_scroll(p_scroll.x);
+		scroll_container->set_v_scroll(p_scroll.y);
+	}
+
+	// Zoom on the position.
+	if (previous_zoom != p_zoom) {
+		// TODO: solve this.
+		// There is however an issue with scrollcainter preventing this, as it seems
+		// that the scrollbars are not updated right aways after its children update.
+
+		// Compute point on previous area.
+		/*Vector2 max = Vector2(scroll_container->get_h_scrollbar()->get_max(), scroll_container->get_v_scrollbar()->get_max());
+		Vector2 min = Vector2(scroll_container->get_h_scrollbar()->get_min(), scroll_container->get_v_scrollbar()->get_min());
+		Vector2 value = Vector2(scroll_container->get_h_scrollbar()->get_value(), scroll_container->get_v_scrollbar()->get_value());
+
+		Vector2 old_max = max * previous_zoom / p_zoom;
+
+		Vector2 max_pixel_change = max - old_max;
+		Vector2 ratio = ((value + scroll_container->get_local_mouse_position()) / old_max).max(Vector2()).min(Vector2(1,1));
+		Vector2 offset = max_pixel_change * ratio;
+
+		print_line("--- ZOOMED ---");
+		print_line(vformat("max: %s", max));
+		print_line(vformat("min: %s", min));
+		print_line(vformat("value: %s", value));
+		print_line(vformat("size: %s", scroll_container->get_size()));
+		print_line(vformat("mouse_pos: %s", scroll_container->get_local_mouse_position()));
+
+		print_line(vformat("ratio: %s", ratio));
+		print_line(vformat("max_pixel_change: %s", max_pixel_change));
+		print_line(vformat("offset: %s", offset));
+
+
+		print_line(vformat("value before: %s", Vector2(scroll_container->get_h_scroll(), scroll_container->get_v_scroll())));
+		scroll_container->set_h_scroll(10000);//scroll_container->get_h_scroll()+offset.x);
+		scroll_container->set_v_scroll(10000);//scroll_container->get_v_scroll()+offset.y);
+		print_line(vformat("value after: %s", Vector2(scroll_container->get_h_scroll(), scroll_container->get_v_scroll())));
+		*/
+
+		previous_zoom = p_zoom;
+	}
+}
+
+void TileAtlasView::_scroll_changed() {
+	emit_signal("transform_changed", zoom_widget->get_zoom(), Vector2(scroll_container->get_h_scroll(), scroll_container->get_v_scroll()));
+}
+
+void TileAtlasView::_zoom_widget_changed() {
+	_update_zoom(zoom_widget->get_zoom());
+	emit_signal("transform_changed", zoom_widget->get_zoom(), Vector2(scroll_container->get_h_scroll(), scroll_container->get_v_scroll()));
+}
+
+void TileAtlasView::_base_tiles_root_control_gui_input(const Ref<InputEvent> &p_event) {
+	base_tiles_root_control->set_tooltip("");
+
+	Ref<InputEventMouseMotion> mm = p_event;
+	if (mm.is_valid()) {
+		Transform2D xform = base_tiles_drawing_root->get_transform().affine_inverse();
+		Vector2i coords = get_atlas_tile_coords_at_pos(xform.xform(mm->get_position()));
+		if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+			coords = tile_set_atlas_source->get_tile_at_coords(coords);
+			if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+				base_tiles_root_control->set_tooltip(vformat(TTR("Source: %d\nAtlas coordinates: %s\nAlternative: 0"), source_id, coords));
+			}
+		}
+	}
+}
+
+void TileAtlasView::_draw_base_tiles() {
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+	if (texture.is_valid()) {
+		Vector2i margins = tile_set_atlas_source->get_margins();
+		Vector2i texture_region_size = tile_set_atlas_source->get_texture_region_size();
+
+		// Draw the texture, square by square.
+		Size2i grid_size = tile_set_atlas_source->get_atlas_grid_size();
+		for (int x = 0; x < grid_size.x; x++) {
+			for (int y = 0; y < grid_size.y; y++) {
+				Vector2i coords = Vector2i(x, y);
+				if (tile_set_atlas_source->get_tile_at_coords(coords) == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					Rect2i rect = Rect2i(texture_region_size * coords + margins, texture_region_size);
+					base_tiles_draw->draw_texture_rect_region(texture, rect, rect);
+				}
+			}
+		}
+
+		// Draw the texture around the grid.
+		Rect2i rect;
+		// Top.
+		rect.position = Vector2i();
+		rect.set_end(Vector2i(texture->get_size().x, margins.y));
+		base_tiles_draw->draw_texture_rect_region(texture, rect, rect);
+		// Bottom
+		rect.position = Vector2i(0, margins.y + (grid_size.y * texture_region_size.y));
+		rect.set_end(texture->get_size());
+		base_tiles_draw->draw_texture_rect_region(texture, rect, rect);
+		// Left
+		rect.position = Vector2i(0, margins.y);
+		rect.set_end(Vector2i(margins.x, margins.y + (grid_size.y * texture_region_size.y)));
+		base_tiles_draw->draw_texture_rect_region(texture, rect, rect);
+		// Right.
+		rect.position = Vector2i(margins.x + (grid_size.x * texture_region_size.x), margins.y);
+		rect.set_end(Vector2i(texture->get_size().x, margins.y + (grid_size.y * texture_region_size.y)));
+		base_tiles_draw->draw_texture_rect_region(texture, rect, rect);
+
+		// Draw actual tiles, using their properties (modulation, etc...)
+		for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+			Vector2i atlas_coords = tile_set_atlas_source->get_tile_id(i);
+
+			// Update the y to max value.
+			Vector2i offset_pos = (margins + (atlas_coords * texture_region_size) + tile_set_atlas_source->get_tile_texture_region(atlas_coords).size / 2 + tile_set_atlas_source->get_tile_effective_texture_offset(atlas_coords, 0));
+
+			// Draw the tile.
+			TileSetAtlasPluginRendering::draw_tile(base_tiles_draw->get_canvas_item(), offset_pos, tile_set, source_id, atlas_coords, 0);
+		}
+	}
+}
+
+void TileAtlasView::_draw_base_tiles_texture_grid() {
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+	if (texture.is_valid()) {
+		Vector2i margins = tile_set_atlas_source->get_margins();
+		Vector2i separation = tile_set_atlas_source->get_separation();
+		Vector2i texture_region_size = tile_set_atlas_source->get_texture_region_size();
+
+		Size2i grid_size = tile_set_atlas_source->get_atlas_grid_size();
+
+		// Draw each tile texture region.
+		for (int x = 0; x < grid_size.x; x++) {
+			for (int y = 0; y < grid_size.y; y++) {
+				Vector2i origin = margins + (Vector2i(x, y) * (texture_region_size + separation));
+				Vector2i base_tile_coords = tile_set_atlas_source->get_tile_at_coords(Vector2i(x, y));
+				if (base_tile_coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					if (base_tile_coords == Vector2i(x, y)) {
+						// Draw existing tile.
+						Vector2i size_in_atlas = tile_set_atlas_source->get_tile_size_in_atlas(base_tile_coords);
+						Vector2 region_size = texture_region_size * size_in_atlas + separation * (size_in_atlas - Vector2i(1, 1));
+						base_tiles_texture_grid->draw_rect(Rect2i(origin, region_size), Color(1.0, 1.0, 1.0, 0.8), false);
+					}
+				} else {
+					// Draw the grid.
+					base_tiles_texture_grid->draw_rect(Rect2i(origin, texture_region_size), Color(0.7, 0.7, 0.7, 0.1), false);
+				}
+			}
+		}
+	}
+}
+
+void TileAtlasView::_draw_base_tiles_dark() {
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+	if (texture.is_valid()) {
+		Vector2i margins = tile_set_atlas_source->get_margins();
+		Vector2i separation = tile_set_atlas_source->get_separation();
+		Vector2i texture_region_size = tile_set_atlas_source->get_texture_region_size();
+
+		Size2i grid_size = tile_set_atlas_source->get_atlas_grid_size();
+
+		// Draw each tile texture region.
+		for (int x = 0; x < grid_size.x; x++) {
+			for (int y = 0; y < grid_size.y; y++) {
+				Vector2i origin = margins + (Vector2i(x, y) * (texture_region_size + separation));
+				Vector2i base_tile_coords = tile_set_atlas_source->get_tile_at_coords(Vector2i(x, y));
+
+				if (base_tile_coords == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					// Draw the grid.
+					base_tiles_dark->draw_rect(Rect2i(origin, texture_region_size), Color(0.0, 0.0, 0.0, 0.5), true);
+				}
+			}
+		}
+	}
+}
+
+void TileAtlasView::_draw_base_tiles_shape_grid() {
+	// Draw the shapes.
+	Vector2i tile_shape_size = tile_set->get_tile_size();
+	for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+		Vector2i tile_id = tile_set_atlas_source->get_tile_id(i);
+		Vector2 in_tile_base_offset = tile_set_atlas_source->get_tile_effective_texture_offset(tile_id, 0);
+		Rect2i texture_region = tile_set_atlas_source->get_tile_texture_region(tile_id);
+		Vector2 origin = texture_region.position + (texture_region.size - tile_shape_size) / 2 + in_tile_base_offset;
+
+		// Draw only if the tile shape fits in the texture region
+		tile_set->draw_tile_shape(base_tiles_shape_grid, Rect2(origin, tile_shape_size), Color(1.0, 0.5, 0.2, 0.8));
+	}
+}
+
+void TileAtlasView::_alternative_tiles_root_control_gui_input(const Ref<InputEvent> &p_event) {
+	alternative_tiles_root_control->set_tooltip("");
+
+	Ref<InputEventMouseMotion> mm = p_event;
+	if (mm.is_valid()) {
+		Transform2D xform = alternative_tiles_drawing_root->get_transform().affine_inverse();
+		Vector3i coords3 = get_alternative_tile_at_pos(xform.xform(mm->get_position()));
+		Vector2i coords = Vector2i(coords3.x, coords3.y);
+		int alternative_id = coords3.z;
+		if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS && alternative_id != TileSetAtlasSource::INVALID_TILE_ALTERNATIVE) {
+			alternative_tiles_root_control->set_tooltip(vformat(TTR("Source: %d\nAtlas coordinates: %s\nAlternative: %d"), source_id, coords, alternative_id));
+		}
+	}
+}
+
+void TileAtlasView::_draw_alternatives() {
+	// Draw the alternative tiles.
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+	if (texture.is_valid()) {
+		Vector2 current_pos;
+		for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+			Vector2i atlas_coords = tile_set_atlas_source->get_tile_id(i);
+			current_pos.x = 0;
+			int y_increment = 0;
+			Rect2i texture_region = tile_set_atlas_source->get_tile_texture_region(atlas_coords);
+			int alternatives_count = tile_set_atlas_source->get_alternative_tiles_count(atlas_coords);
+			for (int j = 1; j < alternatives_count; j++) {
+				int alternative_id = tile_set_atlas_source->get_alternative_tile_id(atlas_coords, j);
+				TileData *tile_data = Object::cast_to<TileData>(tile_set_atlas_source->get_tile_data(atlas_coords, alternative_id));
+				bool transposed = tile_data->get_transpose();
+
+				// Update the y to max value.
+				Vector2i offset_pos = current_pos;
+				if (transposed) {
+					offset_pos = (current_pos + Vector2(texture_region.size.y, texture_region.size.x) / 2 + tile_set_atlas_source->get_tile_effective_texture_offset(atlas_coords, alternative_id));
+					y_increment = MAX(y_increment, texture_region.size.x);
+				} else {
+					offset_pos = (current_pos + texture_region.size / 2 + tile_set_atlas_source->get_tile_effective_texture_offset(atlas_coords, alternative_id));
+					y_increment = MAX(y_increment, texture_region.size.y);
+				}
+
+				// Draw the tile.
+				TileSetAtlasPluginRendering::draw_tile(alternatives_draw->get_canvas_item(), offset_pos, tile_set, source_id, atlas_coords, alternative_id);
+
+				// Increment the x position.
+				current_pos.x += transposed ? texture_region.size.y : texture_region.size.x;
+			}
+			if (alternatives_count > 1) {
+				current_pos.y += y_increment;
+			}
+		}
+	}
+}
+
+void TileAtlasView::_draw_background_left() {
+	Ref<Texture2D> texture = get_theme_icon("Checkerboard", "EditorIcons");
+	background_left->set_size(base_tiles_root_control->get_custom_minimum_size());
+	background_left->draw_texture_rect(texture, Rect2(Vector2(), background_left->get_size()), true);
+}
+
+void TileAtlasView::_draw_background_right() {
+	Ref<Texture2D> texture = get_theme_icon("Checkerboard", "EditorIcons");
+	background_right->set_size(alternative_tiles_root_control->get_custom_minimum_size());
+	background_right->draw_texture_rect(texture, Rect2(Vector2(), background_right->get_size()), true);
+}
+
+void TileAtlasView::set_atlas_source(TileSet *p_tile_set, TileSetAtlasSource *p_tile_set_atlas_source, int p_source_id) {
+	ERR_FAIL_COND(!p_tile_set);
+	ERR_FAIL_COND(!p_tile_set_atlas_source);
+	ERR_FAIL_COND(p_source_id < 0);
+	ERR_FAIL_COND(p_tile_set->get_source(p_source_id) != p_tile_set_atlas_source);
+
+	tile_set = p_tile_set;
+	tile_set_atlas_source = p_tile_set_atlas_source;
+	source_id = p_source_id;
+
+	// Show or hide the view.
+	bool valid = tile_set_atlas_source->get_texture().is_valid();
+	hbox->set_visible(valid);
+	missing_source_label->set_visible(!valid);
+
+	// Update the rect cache.
+	_update_alternative_tiles_rect_cache();
+
+	// Update everything.
+	_update_zoom(zoom_widget->get_zoom());
+
+	// Change children control size.
+	Size2i base_tiles_control_size = _compute_base_tiles_control_size();
+	for (int i = 0; i < base_tiles_drawing_root->get_child_count(); i++) {
+		Control *control = Object::cast_to<Control>(base_tiles_drawing_root->get_child(i));
+		if (control) {
+			control->set_size(base_tiles_control_size);
+		}
+	}
+
+	Size2i alternative_control_size = _compute_alternative_tiles_control_size();
+	for (int i = 0; i < alternative_tiles_drawing_root->get_child_count(); i++) {
+		Control *control = Object::cast_to<Control>(alternative_tiles_drawing_root->get_child(i));
+		if (control) {
+			control->set_size(alternative_control_size);
+		}
+	}
+
+	// Update.
+	base_tiles_draw->update();
+	base_tiles_texture_grid->update();
+	base_tiles_shape_grid->update();
+	base_tiles_dark->update();
+	alternatives_draw->update();
+	background_left->update();
+	background_right->update();
+}
+
+float TileAtlasView::get_zoom() const {
+	return zoom_widget->get_zoom();
+};
+
+void TileAtlasView::set_transform(float p_zoom, Vector2i p_scroll) {
+	zoom_widget->set_zoom(p_zoom);
+	_update_zoom(zoom_widget->get_zoom(), false, p_scroll);
+};
+
+void TileAtlasView::set_padding(Side p_side, int p_padding) {
+	ERR_FAIL_COND(p_padding < 0);
+	margin_container_paddings[p_side] = p_padding;
+}
+
+Vector2i TileAtlasView::get_atlas_tile_coords_at_pos(const Vector2 p_pos) const {
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+	if (texture.is_valid()) {
+		Vector2i margins = tile_set_atlas_source->get_margins();
+		Vector2i separation = tile_set_atlas_source->get_separation();
+		Vector2i texture_region_size = tile_set_atlas_source->get_texture_region_size();
+
+		// Compute index in atlas
+		Vector2 pos = p_pos - margins;
+		Vector2i ret = (pos / (texture_region_size + separation)).floor();
+
+		return ret;
+	}
+
+	return TileSetAtlasSource::INVALID_ATLAS_COORDS;
+}
+
+void TileAtlasView::_update_alternative_tiles_rect_cache() {
+	alternative_tiles_rect_cache.clear();
+
+	Rect2i current;
+	for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+		Vector2i tile_id = tile_set_atlas_source->get_tile_id(i);
+		int alternatives_count = tile_set_atlas_source->get_alternative_tiles_count(tile_id);
+		Size2i texture_region_size = tile_set_atlas_source->get_tile_texture_region(tile_id).size;
+		int line_height = 0;
+		for (int j = 1; j < alternatives_count; j++) {
+			int alternative_id = tile_set_atlas_source->get_alternative_tile_id(tile_id, j);
+			TileData *tile_data = Object::cast_to<TileData>(tile_set_atlas_source->get_tile_data(tile_id, alternative_id));
+			bool transposed = tile_data->get_transpose();
+			current.size = transposed ? Vector2i(texture_region_size.y, texture_region_size.x) : texture_region_size;
+
+			// Update the rect.
+			if (!alternative_tiles_rect_cache.has(tile_id)) {
+				alternative_tiles_rect_cache[tile_id] = Map<int, Rect2i>();
+			}
+			alternative_tiles_rect_cache[tile_id][alternative_id] = current;
+
+			current.position.x += transposed ? texture_region_size.y : texture_region_size.x;
+			line_height = MAX(line_height, transposed ? texture_region_size.x : texture_region_size.y);
+		}
+
+		current.position.x = 0;
+		current.position.y += line_height;
+	}
+}
+
+Vector3i TileAtlasView::get_alternative_tile_at_pos(const Vector2 p_pos) const {
+	for (Map<Vector2, Map<int, Rect2i>>::Element *E_coords = alternative_tiles_rect_cache.front(); E_coords; E_coords = E_coords->next()) {
+		for (Map<int, Rect2i>::Element *E_alternative = E_coords->value().front(); E_alternative; E_alternative = E_alternative->next()) {
+			if (E_alternative->value().has_point(p_pos)) {
+				return Vector3i(E_coords->key().x, E_coords->key().y, E_alternative->key());
+			}
+		}
+	}
+
+	return Vector3i(TileSetAtlasSource::INVALID_ATLAS_COORDS.x, TileSetAtlasSource::INVALID_ATLAS_COORDS.y, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+}
+
+Rect2i TileAtlasView::get_alternative_tile_rect(const Vector2i p_coords, int p_alternative_tile) {
+	ERR_FAIL_COND_V_MSG(!alternative_tiles_rect_cache.has(p_coords), Rect2i(), vformat("No cached rect for tile coords:%s", p_coords));
+	ERR_FAIL_COND_V_MSG(!alternative_tiles_rect_cache[p_coords].has(p_alternative_tile), Rect2i(), vformat("No cached rect for tile coords:%s alternative_id:%d", p_coords, p_alternative_tile));
+
+	return alternative_tiles_rect_cache[p_coords][p_alternative_tile];
+}
+
+void TileAtlasView::update() {
+	scroll_container->update();
+	base_tiles_texture_grid->update();
+	base_tiles_shape_grid->update();
+	base_tiles_dark->update();
+	alternatives_draw->update();
+	background_left->update();
+	background_right->update();
+}
+
+void TileAtlasView::_bind_methods() {
+	ADD_SIGNAL(MethodInfo("transform_changed", PropertyInfo(Variant::FLOAT, "zoom"), PropertyInfo(Variant::VECTOR2, "scroll")));
+}
+
+TileAtlasView::TileAtlasView() {
+	Panel *panel_container = memnew(Panel);
+	panel_container->set_h_size_flags(SIZE_EXPAND_FILL);
+	panel_container->set_v_size_flags(SIZE_EXPAND_FILL);
+	panel_container->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	add_child(panel_container);
+
+	//Scrolling
+	scroll_container = memnew(ScrollContainer);
+	scroll_container->get_h_scrollbar()->connect("value_changed", callable_mp(this, &TileAtlasView::_scroll_changed).unbind(1));
+	scroll_container->get_v_scrollbar()->connect("value_changed", callable_mp(this, &TileAtlasView::_scroll_changed).unbind(1));
+	panel_container->add_child(scroll_container);
+	scroll_container->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+
+	zoom_widget = memnew(EditorZoomWidget);
+	add_child(zoom_widget);
+	zoom_widget->set_anchors_and_offsets_preset(Control::PRESET_TOP_LEFT, Control::PRESET_MODE_MINSIZE, 2 * EDSCALE);
+	zoom_widget->connect("zoom_changed", callable_mp(this, &TileAtlasView::_zoom_widget_changed).unbind(1));
+
+	CenterContainer *center_container = memnew(CenterContainer);
+	center_container->set_h_size_flags(SIZE_EXPAND_FILL);
+	center_container->set_v_size_flags(SIZE_EXPAND_FILL);
+	center_container->connect("gui_input", callable_mp(this, &TileAtlasView::_gui_input));
+	scroll_container->add_child(center_container);
+
+	missing_source_label = memnew(Label);
+	missing_source_label->set_text(TTR("No atlas source with a valid texture selected."));
+	center_container->add_child(missing_source_label);
+
+	margin_container = memnew(MarginContainer);
+	center_container->add_child(margin_container);
+
+	hbox = memnew(HBoxContainer);
+	hbox->add_theme_constant_override("separation", 10);
+	hbox->hide();
+	margin_container->add_child(hbox);
+
+	VBoxContainer *left_vbox = memnew(VBoxContainer);
+	hbox->add_child(left_vbox);
+
+	VBoxContainer *right_vbox = memnew(VBoxContainer);
+	hbox->add_child(right_vbox);
+
+	// Base tiles.
+	Label *base_tile_label = memnew(Label);
+	base_tile_label->set_text(TTR("Base tiles"));
+	base_tile_label->set_align(Label::ALIGN_CENTER);
+	left_vbox->add_child(base_tile_label);
+
+	base_tiles_root_control = memnew(Control);
+	base_tiles_root_control->set_v_size_flags(Control::SIZE_EXPAND_FILL);
+	base_tiles_root_control->connect("gui_input", callable_mp(this, &TileAtlasView::_base_tiles_root_control_gui_input));
+	left_vbox->add_child(base_tiles_root_control);
+
+	background_left = memnew(Control);
+	background_left->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	background_left->set_texture_repeat(TextureRepeat::TEXTURE_REPEAT_ENABLED);
+	background_left->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	background_left->connect("draw", callable_mp(this, &TileAtlasView::_draw_background_left));
+	base_tiles_root_control->add_child(background_left);
+
+	base_tiles_drawing_root = memnew(Control);
+	base_tiles_drawing_root->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	base_tiles_drawing_root->set_texture_filter(TEXTURE_FILTER_NEAREST);
+	base_tiles_drawing_root->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	base_tiles_root_control->add_child(base_tiles_drawing_root);
+
+	base_tiles_draw = memnew(Control);
+	base_tiles_draw->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	base_tiles_draw->connect("draw", callable_mp(this, &TileAtlasView::_draw_base_tiles));
+	base_tiles_draw->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	base_tiles_drawing_root->add_child(base_tiles_draw);
+
+	base_tiles_texture_grid = memnew(Control);
+	base_tiles_texture_grid->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	base_tiles_texture_grid->connect("draw", callable_mp(this, &TileAtlasView::_draw_base_tiles_texture_grid));
+	base_tiles_texture_grid->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	base_tiles_drawing_root->add_child(base_tiles_texture_grid);
+
+	base_tiles_shape_grid = memnew(Control);
+	base_tiles_shape_grid->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	base_tiles_shape_grid->connect("draw", callable_mp(this, &TileAtlasView::_draw_base_tiles_shape_grid));
+	base_tiles_shape_grid->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	base_tiles_drawing_root->add_child(base_tiles_shape_grid);
+
+	base_tiles_dark = memnew(Control);
+	base_tiles_dark->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	base_tiles_dark->connect("draw", callable_mp(this, &TileAtlasView::_draw_base_tiles_dark));
+	base_tiles_dark->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	base_tiles_drawing_root->add_child(base_tiles_dark);
+
+	// Alternative tiles.
+	Label *alternative_tiles_label = memnew(Label);
+	alternative_tiles_label->set_text(TTR("Alternative tiles"));
+	alternative_tiles_label->set_align(Label::ALIGN_CENTER);
+	right_vbox->add_child(alternative_tiles_label);
+
+	alternative_tiles_root_control = memnew(Control);
+	alternative_tiles_root_control->connect("gui_input", callable_mp(this, &TileAtlasView::_alternative_tiles_root_control_gui_input));
+	right_vbox->add_child(alternative_tiles_root_control);
+
+	background_right = memnew(Control);
+	background_right->set_texture_repeat(TextureRepeat::TEXTURE_REPEAT_ENABLED);
+	background_right->connect("draw", callable_mp(this, &TileAtlasView::_draw_background_right));
+	background_right->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	alternative_tiles_root_control->add_child(background_right);
+
+	alternative_tiles_drawing_root = memnew(Control);
+	alternative_tiles_drawing_root->set_texture_filter(TEXTURE_FILTER_NEAREST);
+	alternative_tiles_drawing_root->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	alternative_tiles_root_control->add_child(alternative_tiles_drawing_root);
+
+	alternatives_draw = memnew(Control);
+	alternatives_draw->connect("draw", callable_mp(this, &TileAtlasView::_draw_alternatives));
+	alternatives_draw->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+	alternative_tiles_drawing_root->add_child(alternatives_draw);
+}
diff --git a/editor/plugins/tiles/tile_atlas_view.h b/editor/plugins/tiles/tile_atlas_view.h
new file mode 100644
index 0000000000..28fd3ed1e0
--- /dev/null
+++ b/editor/plugins/tiles/tile_atlas_view.h
@@ -0,0 +1,153 @@
+/*************************************************************************/
+/*  tile_atlas_view.h                                                    */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef TILE_ATLAS_VIEW_H
+#define TILE_ATLAS_VIEW_H
+
+#include "editor/editor_zoom_widget.h"
+#include "scene/gui/box_container.h"
+#include "scene/gui/button.h"
+#include "scene/gui/label.h"
+#include "scene/gui/margin_container.h"
+#include "scene/gui/scroll_container.h"
+#include "scene/gui/texture_rect.h"
+#include "scene/resources/tile_set.h"
+
+class TileAtlasView : public Control {
+	GDCLASS(TileAtlasView, Control);
+
+private:
+	TileSet *tile_set;
+	TileSetAtlasSource *tile_set_atlas_source;
+	int source_id = -1;
+
+	float previous_zoom = 1.0;
+	EditorZoomWidget *zoom_widget;
+	void _zoom_widget_changed();
+	void _scroll_changed();
+	void _update_zoom(float p_zoom, bool p_zoom_on_mouse_pos = false, Vector2i p_scroll = Vector2i(-1, -1));
+	void _gui_input(const Ref<InputEvent> &p_event);
+
+	Map<Vector2, Map<int, Rect2i>> alternative_tiles_rect_cache;
+	void _update_alternative_tiles_rect_cache();
+
+	ScrollContainer *scroll_container;
+	MarginContainer *margin_container;
+	int margin_container_paddings[4] = { 0, 0, 0, 0 };
+	HBoxContainer *hbox;
+	Label *missing_source_label;
+
+	// Background
+	Control *background_left;
+	void _draw_background_left();
+	Control *background_right;
+	void _draw_background_right();
+
+	// Left side.
+	Control *base_tiles_root_control;
+	void _base_tiles_root_control_gui_input(const Ref<InputEvent> &p_event);
+
+	Control *base_tiles_drawing_root;
+
+	Control *base_tiles_draw;
+	void _draw_base_tiles();
+
+	Control *base_tiles_texture_grid;
+	void _draw_base_tiles_texture_grid();
+
+	Control *base_tiles_shape_grid;
+	void _draw_base_tiles_shape_grid();
+
+	Control *base_tiles_dark;
+	void _draw_base_tiles_dark();
+
+	Size2i _compute_base_tiles_control_size();
+
+	// Right side.
+	Control *alternative_tiles_root_control;
+	void _alternative_tiles_root_control_gui_input(const Ref<InputEvent> &p_event);
+
+	Control *alternative_tiles_drawing_root;
+
+	Control *alternatives_draw;
+	void _draw_alternatives();
+
+	Size2i _compute_alternative_tiles_control_size();
+
+protected:
+	static void _bind_methods();
+
+public:
+	// Global.
+	void set_atlas_source(TileSet *p_tile_set, TileSetAtlasSource *p_tile_set_atlas_source, int p_source_id);
+
+	ScrollContainer *get_scroll_container() { return scroll_container; };
+
+	float get_zoom() const;
+	void set_transform(float p_zoom, Vector2i p_scroll);
+
+	void set_padding(Side p_side, int p_padding);
+
+	// Left side.
+	void set_texture_grid_visible(bool p_visible) { base_tiles_texture_grid->set_visible(p_visible); };
+	void set_dark_visible(bool p_visible) { base_tiles_dark->set_visible(p_visible); };
+	void set_tile_shape_grid_visible(bool p_visible) { base_tiles_shape_grid->set_visible(p_visible); };
+
+	Vector2i get_atlas_tile_coords_at_pos(const Vector2 p_pos) const;
+
+	void add_control_over_atlas_tiles(Control *p_control, bool scaled = true) {
+		if (scaled) {
+			base_tiles_drawing_root->add_child(p_control);
+		} else {
+			base_tiles_root_control->add_child(p_control);
+		}
+		p_control->set_mouse_filter(Control::MOUSE_FILTER_PASS);
+	};
+
+	// Right side.
+	Vector3i get_alternative_tile_at_pos(const Vector2 p_pos) const;
+	Rect2i get_alternative_tile_rect(const Vector2i p_coords, int p_alternative_tile);
+
+	void add_control_over_alternative_tiles(Control *p_control, bool scaled = true) {
+		if (scaled) {
+			alternative_tiles_drawing_root->add_child(p_control);
+		} else {
+			alternative_tiles_root_control->add_child(p_control);
+		}
+		p_control->set_mouse_filter(Control::MOUSE_FILTER_PASS);
+	};
+
+	// Update everything.
+	void update();
+
+	TileAtlasView();
+};
+
+#endif // TILE_ATLAS_VIEW
diff --git a/editor/plugins/tiles/tile_data_editors.cpp b/editor/plugins/tiles/tile_data_editors.cpp
new file mode 100644
index 0000000000..0b674bec39
--- /dev/null
+++ b/editor/plugins/tiles/tile_data_editors.cpp
@@ -0,0 +1,218 @@
+/*************************************************************************/
+/*  tile_data_editors.cpp                                                */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "tile_data_editors.h"
+
+#include "tile_set_editor.h"
+
+TileData *TileDataEditor::_get_tile_data(TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile) {
+	ERR_FAIL_COND_V(!p_tile_set, nullptr);
+	ERR_FAIL_COND_V(!p_tile_set->has_source(p_atlas_source_id), nullptr);
+
+	TileData *td = nullptr;
+	TileSetSource *source = *p_tile_set->get_source(p_atlas_source_id);
+	TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
+	if (atlas_source) {
+		ERR_FAIL_COND_V(!atlas_source->has_tile(p_atlas_coords), nullptr);
+		ERR_FAIL_COND_V(!atlas_source->has_alternative_tile(p_atlas_coords, p_alternative_tile), nullptr);
+		td = Object::cast_to<TileData>(atlas_source->get_tile_data(p_atlas_coords, p_alternative_tile));
+	}
+
+	return td;
+}
+
+void TileDataEditor::edit(TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+}
+
+void TileDataTextureOffsetEditor::draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+	TileData *tile_data = _get_tile_data(p_tile_set, p_atlas_source_id, p_atlas_coords, p_alternative_tile);
+	ERR_FAIL_COND(!tile_data);
+
+	bool valid;
+	Variant value = tile_data->get(p_property, &valid);
+	if (!valid) {
+		return;
+	}
+	ERR_FAIL_COND(value.get_type() != Variant::VECTOR2I);
+
+	Vector2i tile_set_tile_size = p_tile_set->get_tile_size();
+	Rect2i rect = Rect2i(-tile_set_tile_size / 2, tile_set_tile_size);
+	p_tile_set->draw_tile_shape(p_canvas_item, p_transform.xform(rect), Color(1.0, 0.0, 0.0));
+}
+
+void TileDataIntegerEditor::draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+	TileData *tile_data = _get_tile_data(p_tile_set, p_atlas_source_id, p_atlas_coords, p_alternative_tile);
+	ERR_FAIL_COND(!tile_data);
+
+	bool valid;
+	Variant value = tile_data->get(p_property, &valid);
+	if (!valid) {
+		return;
+	}
+	ERR_FAIL_COND(value.get_type() != Variant::INT);
+
+	Ref<Font> font = TileSetEditor::get_singleton()->get_theme_font("bold", "EditorFonts");
+	int height = font->get_height();
+	int width = 200;
+	p_canvas_item->draw_string(font, p_transform.get_origin() + Vector2i(-width / 2, height / 2), vformat("%d", value), HALIGN_CENTER, width, -1, Color(1, 1, 1), 1, Color(0, 0, 0, 1));
+}
+
+void TileDataFloatEditor::draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+	TileData *tile_data = _get_tile_data(p_tile_set, p_atlas_source_id, p_atlas_coords, p_alternative_tile);
+	ERR_FAIL_COND(!tile_data);
+
+	bool valid;
+	Variant value = tile_data->get(p_property, &valid);
+	if (!valid) {
+		return;
+	}
+	ERR_FAIL_COND(value.get_type() != Variant::FLOAT);
+
+	Ref<Font> font = TileSetEditor::get_singleton()->get_theme_font("bold", "EditorFonts");
+	int height = font->get_height();
+	int width = 200;
+	p_canvas_item->draw_string(font, p_transform.get_origin() + Vector2i(-width / 2, height / 2), vformat("%.2f", value), HALIGN_CENTER, width, -1, Color(1, 1, 1), 1, Color(0, 0, 0, 1));
+}
+
+void TileDataPositionEditor::draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+	TileData *tile_data = _get_tile_data(p_tile_set, p_atlas_source_id, p_atlas_coords, p_alternative_tile);
+	ERR_FAIL_COND(!tile_data);
+
+	bool valid;
+	Variant value = tile_data->get(p_property, &valid);
+	if (!valid) {
+		return;
+	}
+	ERR_FAIL_COND(value.get_type() != Variant::VECTOR2I && value.get_type() != Variant::VECTOR2);
+
+	Ref<Texture2D> position_icon = TileSetEditor::get_singleton()->get_theme_icon("EditorPosition", "EditorIcons");
+	p_canvas_item->draw_texture(position_icon, p_transform.get_origin() + Vector2(value) - position_icon->get_size() / 2);
+}
+
+void TileDataOcclusionShapeEditor::draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+	TileData *tile_data = _get_tile_data(p_tile_set, p_atlas_source_id, p_atlas_coords, p_alternative_tile);
+	ERR_FAIL_COND(!tile_data);
+
+	Vector<String> components = String(p_property).split("/", true);
+	if (components[0].begins_with("occlusion_layer_") && components[0].trim_prefix("occlusion_layer_").is_valid_integer()) {
+		int occlusion_layer = components[0].trim_prefix("occlusion_layer_").to_int();
+		if (occlusion_layer >= 0 && occlusion_layer < p_tile_set->get_occlusion_layers_count()) {
+			// Draw all shapes.
+			Vector<Color> debug_occlusion_color;
+			debug_occlusion_color.push_back(Color(0.5, 0, 0, 0.6));
+
+			RenderingServer::get_singleton()->canvas_item_add_set_transform(p_canvas_item->get_canvas_item(), p_transform);
+			Ref<OccluderPolygon2D> occluder = tile_data->get_occluder(occlusion_layer);
+			if (occluder.is_valid() && occluder->get_polygon().size() >= 3) {
+				p_canvas_item->draw_polygon(Variant(occluder->get_polygon()), debug_occlusion_color);
+			}
+			RenderingServer::get_singleton()->canvas_item_add_set_transform(p_canvas_item->get_canvas_item(), Transform2D());
+		}
+	}
+}
+
+void TileDataCollisionShapeEditor::draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+	TileData *tile_data = _get_tile_data(p_tile_set, p_atlas_source_id, p_atlas_coords, p_alternative_tile);
+	ERR_FAIL_COND(!tile_data);
+
+	Vector<String> components = String(p_property).split("/", true);
+	if (components[0].begins_with("physics_layer_") && components[0].trim_prefix("physics_layer_").is_valid_integer()) {
+		int physics_layer = components[0].trim_prefix("physics_layer_").to_int();
+		if (physics_layer >= 0 && physics_layer < p_tile_set->get_physics_layers_count()) {
+			// Draw all shapes.
+			Color debug_collision_color = p_canvas_item->get_tree()->get_debug_collisions_color();
+			RenderingServer::get_singleton()->canvas_item_add_set_transform(p_canvas_item->get_canvas_item(), p_transform);
+			for (int i = 0; i < tile_data->get_collision_shapes_count(physics_layer); i++) {
+				Ref<Shape2D> shape = tile_data->get_collision_shape_shape(physics_layer, i);
+				if (shape.is_valid()) {
+					shape->draw(p_canvas_item->get_canvas_item(), debug_collision_color);
+				}
+			}
+			RenderingServer::get_singleton()->canvas_item_add_set_transform(p_canvas_item->get_canvas_item(), Transform2D());
+		}
+	}
+}
+
+void TileDataTerrainsEditor::draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+	TileData *tile_data = _get_tile_data(p_tile_set, p_atlas_source_id, p_atlas_coords, p_alternative_tile);
+	ERR_FAIL_COND(!tile_data);
+
+	Vector<String> components = String(p_property).split("/", true);
+	if (components[0] == "terrain_mode" || components[0] == "terrain" || components[0] == "terrains_peering_bit") {
+		TileSetAtlasPluginTerrain::draw_terrains(p_canvas_item, p_transform, p_tile_set, tile_data);
+	}
+}
+
+void TileDataNavigationPolygonEditor::draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) {
+	TileData *tile_data = _get_tile_data(p_tile_set, p_atlas_source_id, p_atlas_coords, p_alternative_tile);
+	ERR_FAIL_COND(!tile_data);
+
+	Vector<String> components = String(p_property).split("/", true);
+	if (components[0].begins_with("navigation_layer_") && components[0].trim_prefix("navigation_layer_").is_valid_integer()) {
+		int navigation_layer = components[0].trim_prefix("navigation_layer_").to_int();
+		if (navigation_layer >= 0 && navigation_layer < p_tile_set->get_navigation_layers_count()) {
+			// Draw all shapes.
+			RenderingServer::get_singleton()->canvas_item_add_set_transform(p_canvas_item->get_canvas_item(), p_transform);
+
+			Ref<NavigationPolygon> navigation_polygon = tile_data->get_navigation_polygon(navigation_layer);
+			if (navigation_polygon.is_valid()) {
+				Vector<Vector2> verts = navigation_polygon->get_vertices();
+				if (verts.size() < 3) {
+					return;
+				}
+
+				Color color = p_canvas_item->get_tree()->get_debug_navigation_color();
+
+				RandomPCG rand;
+				for (int i = 0; i < navigation_polygon->get_polygon_count(); i++) {
+					// An array of vertices for this polygon.
+					Vector<int> polygon = navigation_polygon->get_polygon(i);
+					Vector<Vector2> vertices;
+					vertices.resize(polygon.size());
+					for (int j = 0; j < polygon.size(); j++) {
+						ERR_FAIL_INDEX(polygon[j], verts.size());
+						vertices.write[j] = verts[polygon[j]];
+					}
+
+					// Generate the polygon color, slightly randomly modified from the settings one.
+					Color random_variation_color;
+					random_variation_color.set_hsv(color.get_h() + rand.random(-1.0, 1.0) * 0.05, color.get_s(), color.get_v() + rand.random(-1.0, 1.0) * 0.1);
+					random_variation_color.a = color.a;
+					Vector<Color> colors;
+					colors.push_back(random_variation_color);
+
+					RenderingServer::get_singleton()->canvas_item_add_polygon(p_canvas_item->get_canvas_item(), vertices, colors);
+				}
+			}
+
+			RenderingServer::get_singleton()->canvas_item_add_set_transform(p_canvas_item->get_canvas_item(), Transform2D());
+		}
+	}
+}
diff --git a/editor/plugins/tiles/tile_data_editors.h b/editor/plugins/tiles/tile_data_editors.h
new file mode 100644
index 0000000000..f4f9c25157
--- /dev/null
+++ b/editor/plugins/tiles/tile_data_editors.h
@@ -0,0 +1,110 @@
+/*************************************************************************/
+/*  tile_data_editors.h                                                  */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef TILE_DATA_EDITORS_H
+#define TILE_DATA_EDITORS_H
+
+#include "scene/gui/control.h"
+#include "scene/resources/tile_set.h"
+
+class TileDataEditor : public Control {
+	GDCLASS(TileDataEditor, Control);
+
+protected:
+	TileData *tile_data;
+	String property;
+
+	TileData *_get_tile_data(TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile);
+
+public:
+	// Edits a TileData property.
+	void edit(TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property);
+
+	// Used to draw the value over a tile.
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property){};
+};
+
+class TileDataTextureOffsetEditor : public TileDataEditor {
+	GDCLASS(TileDataTextureOffsetEditor, TileDataEditor);
+
+public:
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) override;
+};
+
+class TileDataIntegerEditor : public TileDataEditor {
+	GDCLASS(TileDataIntegerEditor, TileDataEditor);
+
+public:
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) override;
+};
+
+class TileDataFloatEditor : public TileDataEditor {
+	GDCLASS(TileDataFloatEditor, TileDataEditor);
+
+public:
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) override;
+};
+
+class TileDataPositionEditor : public TileDataEditor {
+	GDCLASS(TileDataPositionEditor, TileDataEditor);
+
+public:
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) override;
+};
+
+class TileDataOcclusionShapeEditor : public TileDataEditor {
+	GDCLASS(TileDataOcclusionShapeEditor, TileDataEditor);
+
+public:
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) override;
+};
+
+class TileDataCollisionShapeEditor : public TileDataEditor {
+	GDCLASS(TileDataCollisionShapeEditor, TileDataEditor);
+
+public:
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) override;
+};
+
+class TileDataTerrainsEditor : public TileDataEditor {
+	GDCLASS(TileDataTerrainsEditor, TileDataEditor);
+
+public:
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) override;
+};
+
+class TileDataNavigationPolygonEditor : public TileDataEditor {
+	GDCLASS(TileDataNavigationPolygonEditor, TileDataEditor);
+
+public:
+	virtual void draw_over_tile(CanvasItem *p_canvas_item, Transform2D p_transform, TileSet *p_tile_set, int p_atlas_source_id, Vector2i p_atlas_coords, int p_alternative_tile, String p_property) override;
+};
+
+#endif // TILE_DATA_EDITORS_H
diff --git a/editor/plugins/tiles/tile_map_editor.cpp b/editor/plugins/tiles/tile_map_editor.cpp
new file mode 100644
index 0000000000..cfc4dff329
--- /dev/null
+++ b/editor/plugins/tiles/tile_map_editor.cpp
@@ -0,0 +1,3368 @@
+/*************************************************************************/
+/*  tile_map_editor.cpp                                                  */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "tile_map_editor.h"
+
+#include "tiles_editor_plugin.h"
+
+#include "editor/editor_scale.h"
+#include "editor/plugins/canvas_item_editor_plugin.h"
+
+#include "scene/gui/center_container.h"
+#include "scene/gui/split_container.h"
+
+#include "core/input/input.h"
+#include "core/math/geometry_2d.h"
+#include "core/os/keyboard.h"
+
+void TileMapEditorTilesPlugin::_notification(int p_what) {
+	switch (p_what) {
+		case NOTIFICATION_ENTER_TREE:
+		case NOTIFICATION_THEME_CHANGED:
+			select_tool_button->set_icon(get_theme_icon("ToolSelect", "EditorIcons"));
+			paint_tool_button->set_icon(get_theme_icon("Edit", "EditorIcons"));
+			line_tool_button->set_icon(get_theme_icon("CurveLinear", "EditorIcons"));
+			rect_tool_button->set_icon(get_theme_icon("Rectangle", "EditorIcons"));
+			bucket_tool_button->set_icon(get_theme_icon("Bucket", "EditorIcons"));
+
+			picker_button->set_icon(get_theme_icon("ColorPick", "EditorIcons"));
+			erase_button->set_icon(get_theme_icon("Eraser", "EditorIcons"));
+
+			missing_texture_texture = get_theme_icon("TileSet", "EditorIcons");
+			break;
+		case NOTIFICATION_VISIBILITY_CHANGED:
+			_stop_dragging();
+	}
+}
+
+void TileMapEditorTilesPlugin::tile_set_changed() {
+	_update_fix_selected_and_hovered();
+	_update_bottom_panel();
+	_update_tile_set_sources_list();
+	_update_atlas_view();
+}
+
+void TileMapEditorTilesPlugin::_on_random_tile_checkbox_toggled(bool p_pressed) {
+	scatter_spinbox->set_editable(p_pressed);
+}
+
+void TileMapEditorTilesPlugin::_on_scattering_spinbox_changed(double p_value) {
+	scattering = p_value;
+}
+
+void TileMapEditorTilesPlugin::_update_toolbar() {
+	// Stop draggig if needed.
+	_stop_dragging();
+
+	// Hide all settings.
+	for (int i = 0; i < tools_settings->get_child_count(); i++) {
+		Object::cast_to<CanvasItem>(tools_settings->get_child(i))->hide();
+	}
+
+	// Show only the correct settings.
+	if (tool_buttons_group->get_pressed_button() == select_tool_button) {
+	} else if (tool_buttons_group->get_pressed_button() == paint_tool_button) {
+		tools_settings_vsep->show();
+		picker_button->show();
+		erase_button->show();
+		tools_settings_vsep_2->show();
+		random_tile_checkbox->show();
+		scatter_label->show();
+		scatter_spinbox->show();
+	} else if (tool_buttons_group->get_pressed_button() == line_tool_button) {
+		tools_settings_vsep->show();
+		picker_button->show();
+		erase_button->show();
+		tools_settings_vsep_2->show();
+		random_tile_checkbox->show();
+		scatter_label->show();
+		scatter_spinbox->show();
+	} else if (tool_buttons_group->get_pressed_button() == rect_tool_button) {
+		tools_settings_vsep->show();
+		picker_button->show();
+		erase_button->show();
+		tools_settings_vsep_2->show();
+		random_tile_checkbox->show();
+		scatter_label->show();
+		scatter_spinbox->show();
+	} else if (tool_buttons_group->get_pressed_button() == bucket_tool_button) {
+		tools_settings_vsep->show();
+		picker_button->show();
+		erase_button->show();
+		tools_settings_vsep_2->show();
+		bucket_continuous_checkbox->show();
+		random_tile_checkbox->show();
+		scatter_label->show();
+		scatter_spinbox->show();
+	}
+}
+
+Control *TileMapEditorTilesPlugin::get_toolbar() const {
+	return toolbar;
+}
+
+void TileMapEditorTilesPlugin::_update_tile_set_sources_list() {
+	// Update the sources.
+	int old_current = sources_list->get_current();
+	sources_list->clear();
+
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	for (int i = 0; i < tile_set->get_source_count(); i++) {
+		int source_id = tile_set->get_source_id(i);
+
+		// TODO: handle with virtual functions
+		TileSetSource *source = *tile_set->get_source(source_id);
+		TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
+		if (atlas_source) {
+			Ref<Texture2D> texture = atlas_source->get_texture();
+			if (texture.is_valid()) {
+				sources_list->add_item(vformat("%s - (id:%d)", texture->get_path().get_file(), source_id), texture);
+			} else {
+				sources_list->add_item(vformat("No texture atlas source - (id:%d)", source_id), missing_texture_texture);
+			}
+		} else {
+			sources_list->add_item(vformat("Unknown type source - (id:%d)", source_id), missing_texture_texture);
+		}
+		sources_list->set_item_metadata(i, source_id);
+	}
+
+	if (sources_list->get_item_count() > 0) {
+		if (old_current > 0) {
+			// Keep the current selected item if needed.
+			sources_list->set_current(CLAMP(old_current, 0, sources_list->get_item_count() - 1));
+		} else {
+			sources_list->set_current(0);
+		}
+		sources_list->emit_signal("item_selected", sources_list->get_current());
+	}
+
+	// Synchronize
+	TilesEditor::get_singleton()->set_atlas_sources_lists_current(sources_list->get_current());
+}
+
+void TileMapEditorTilesPlugin::_update_atlas_view() {
+	// Update the atlas display.
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		tile_atlas_view->hide();
+		return;
+	}
+
+	int source_index = sources_list->get_current();
+	if (source_index >= 0 && source_index < sources_list->get_item_count()) {
+		int source_id = sources_list->get_item_metadata(source_index);
+		TileSetSource *source = *tile_set->get_source(source_id);
+		TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
+		if (atlas_source) {
+			tile_atlas_view->set_atlas_source(*tile_map->get_tileset(), atlas_source, source_id);
+			tile_atlas_view->show();
+		}
+	} else {
+		tile_atlas_view->hide();
+	}
+
+	// Synchronize atlas view.
+	TilesEditor::get_singleton()->synchronize_atlas_view(tile_atlas_view);
+
+	tile_atlas_control->update();
+}
+
+void TileMapEditorTilesPlugin::_update_bottom_panel() {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+
+	// Update the tabs.
+	missing_source_label->set_visible(tile_set.is_valid() && tile_set->get_source_count() == 0);
+	atlas_sources_split_container->set_visible(tile_set.is_valid() && tile_set->get_source_count() > 0);
+}
+
+bool TileMapEditorTilesPlugin::forward_canvas_gui_input(const Ref<InputEvent> &p_event) {
+	if (!is_visible_in_tree()) {
+		// If the bottom editor is not visible, we ignore inputs.
+		return false;
+	}
+
+	if (CanvasItemEditor::get_singleton()->get_current_tool() != CanvasItemEditor::TOOL_SELECT) {
+		return false;
+	}
+
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return false;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return false;
+	}
+
+	// Shortcuts
+	if (ED_IS_SHORTCUT("tiles_editor/cut", p_event) || ED_IS_SHORTCUT("tiles_editor/copy", p_event)) {
+		// Fill in the clipboard.
+		if (!tile_map_selection.is_empty()) {
+			memdelete(tile_map_clipboard);
+			TypedArray<Vector2i> coords_array;
+			for (Set<Vector2i>::Element *E = tile_map_selection.front(); E; E = E->next()) {
+				coords_array.push_back(E->get());
+			}
+			tile_map_clipboard = tile_map->get_pattern(coords_array);
+		}
+
+		if (ED_IS_SHORTCUT("tiles_editor/cut", p_event)) {
+			// Delete selected tiles.
+			if (!tile_map_selection.is_empty()) {
+				undo_redo->create_action(TTR("Delete tiles"));
+				for (Set<Vector2i>::Element *E = tile_map_selection.front(); E; E = E->next()) {
+					undo_redo->add_do_method(tile_map, "set_cell", E->get(), -1, TileSetAtlasSource::INVALID_ATLAS_COORDS, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+					undo_redo->add_undo_method(tile_map, "set_cell", E->get(), tile_map->get_cell_source_id(E->get()), tile_map->get_cell_atlas_coords(E->get()), tile_map->get_cell_alternative_tile(E->get()));
+				}
+				undo_redo->add_undo_method(this, "_set_tile_map_selection", _get_tile_map_selection());
+				tile_map_selection.clear();
+				undo_redo->add_do_method(this, "_set_tile_map_selection", _get_tile_map_selection());
+				undo_redo->commit_action();
+			}
+		}
+
+		return true;
+	}
+	if (ED_IS_SHORTCUT("tiles_editor/paste", p_event)) {
+		if (drag_type == DRAG_TYPE_NONE) {
+			drag_type = DRAG_TYPE_CLIPBOARD_PASTE;
+		}
+		CanvasItemEditor::get_singleton()->update_viewport();
+		return true;
+	}
+	if (ED_IS_SHORTCUT("tiles_editor/cancel", p_event)) {
+		if (drag_type == DRAG_TYPE_CLIPBOARD_PASTE) {
+			drag_type = DRAG_TYPE_NONE;
+			CanvasItemEditor::get_singleton()->update_viewport();
+			return true;
+		}
+	}
+	if (ED_IS_SHORTCUT("tiles_editor/delete", p_event)) {
+		// Delete selected tiles.
+		if (!tile_map_selection.is_empty()) {
+			undo_redo->create_action(TTR("Delete tiles"));
+			for (Set<Vector2i>::Element *E = tile_map_selection.front(); E; E = E->next()) {
+				undo_redo->add_do_method(tile_map, "set_cell", E->get(), -1, TileSetAtlasSource::INVALID_ATLAS_COORDS, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+				undo_redo->add_undo_method(tile_map, "set_cell", E->get(), tile_map->get_cell_source_id(E->get()), tile_map->get_cell_atlas_coords(E->get()), tile_map->get_cell_alternative_tile(E->get()));
+			}
+			undo_redo->add_undo_method(this, "_set_tile_map_selection", _get_tile_map_selection());
+			tile_map_selection.clear();
+			undo_redo->add_do_method(this, "_set_tile_map_selection", _get_tile_map_selection());
+			undo_redo->commit_action();
+		}
+		return true;
+	}
+
+	Ref<InputEventMouseMotion> mm = p_event;
+	if (mm.is_valid()) {
+		has_mouse = true;
+		Transform2D xform = CanvasItemEditor::get_singleton()->get_canvas_transform() * tile_map->get_global_transform();
+		Vector2 mpos = xform.affine_inverse().xform(mm->get_position());
+
+		switch (drag_type) {
+			case DRAG_TYPE_PAINT: {
+				Map<Vector2i, TileMapCell> to_draw = _draw_line(drag_start_mouse_pos, drag_last_mouse_pos, mpos);
+				for (Map<Vector2i, TileMapCell>::Element *E = to_draw.front(); E; E = E->next()) {
+					if (!erase_button->is_pressed() && E->get().source_id == -1) {
+						continue;
+					}
+					Vector2i coords = E->key();
+					if (!drag_modified.has(coords)) {
+						drag_modified.insert(coords, TileMapCell(tile_map->get_cell_source_id(coords), tile_map->get_cell_atlas_coords(coords), tile_map->get_cell_alternative_tile(coords)));
+					}
+					tile_map->set_cell(coords, E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+				}
+			} break;
+			case DRAG_TYPE_BUCKET: {
+				Vector<Vector2i> line = TileMapEditor::get_line(tile_map, tile_map->world_to_map(drag_last_mouse_pos), tile_map->world_to_map(mpos));
+				for (int i = 0; i < line.size(); i++) {
+					if (!drag_modified.has(line[i])) {
+						Map<Vector2i, TileMapCell> to_draw = _draw_bucket_fill(line[i], bucket_continuous_checkbox->is_pressed());
+						for (Map<Vector2i, TileMapCell>::Element *E = to_draw.front(); E; E = E->next()) {
+							if (!erase_button->is_pressed() && E->get().source_id == -1) {
+								continue;
+							}
+							Vector2i coords = E->key();
+							if (!drag_modified.has(coords)) {
+								drag_modified.insert(coords, TileMapCell(tile_map->get_cell_source_id(coords), tile_map->get_cell_atlas_coords(coords), tile_map->get_cell_alternative_tile(coords)));
+							}
+							tile_map->set_cell(coords, E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+						}
+					}
+				}
+			} break;
+			default:
+				break;
+		}
+		drag_last_mouse_pos = mpos;
+		CanvasItemEditor::get_singleton()->update_viewport();
+
+		return true;
+	}
+
+	Ref<InputEventMouseButton> mb = p_event;
+	if (mb.is_valid()) {
+		has_mouse = true;
+		Transform2D xform = CanvasItemEditor::get_singleton()->get_canvas_transform() * tile_map->get_global_transform();
+		Vector2 mpos = xform.affine_inverse().xform(mb->get_position());
+
+		if (mb->get_button_index() == MOUSE_BUTTON_LEFT) {
+			if (mb->is_pressed()) {
+				// Pressed
+				if (tool_buttons_group->get_pressed_button() == select_tool_button) {
+					drag_start_mouse_pos = mpos;
+					if (tile_map_selection.has(tile_map->world_to_map(drag_start_mouse_pos)) && !mb->get_shift()) {
+						// Move the selection
+						drag_type = DRAG_TYPE_MOVE;
+						drag_modified.clear();
+						for (Set<Vector2i>::Element *E = tile_map_selection.front(); E; E = E->next()) {
+							Vector2i coords = E->get();
+							drag_modified.insert(coords, TileMapCell(tile_map->get_cell_source_id(coords), tile_map->get_cell_atlas_coords(coords), tile_map->get_cell_alternative_tile(coords)));
+							tile_map->set_cell(coords, -1, TileSetAtlasSource::INVALID_ATLAS_COORDS, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+						}
+					} else {
+						// Select tiles
+						drag_type = DRAG_TYPE_SELECT;
+					}
+				} else {
+					// Check if we are picking a tile.
+					if (picker_button->is_pressed()) {
+						drag_type = DRAG_TYPE_PICK;
+						drag_start_mouse_pos = mpos;
+					} else {
+						// Paint otherwise.
+						if (tool_buttons_group->get_pressed_button() == paint_tool_button) {
+							drag_type = DRAG_TYPE_PAINT;
+							drag_start_mouse_pos = mpos;
+							drag_modified.clear();
+							Map<Vector2i, TileMapCell> to_draw = _draw_line(drag_start_mouse_pos, mpos, mpos);
+							for (Map<Vector2i, TileMapCell>::Element *E = to_draw.front(); E; E = E->next()) {
+								if (!erase_button->is_pressed() && E->get().source_id == -1) {
+									continue;
+								}
+								Vector2i coords = E->key();
+								if (!drag_modified.has(coords)) {
+									drag_modified.insert(coords, TileMapCell(tile_map->get_cell_source_id(coords), tile_map->get_cell_atlas_coords(coords), tile_map->get_cell_alternative_tile(coords)));
+								}
+								tile_map->set_cell(coords, E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+							}
+						} else if (tool_buttons_group->get_pressed_button() == line_tool_button) {
+							drag_type = DRAG_TYPE_LINE;
+							drag_start_mouse_pos = mpos;
+							drag_modified.clear();
+						} else if (tool_buttons_group->get_pressed_button() == rect_tool_button) {
+							drag_type = DRAG_TYPE_RECT;
+							drag_start_mouse_pos = mpos;
+							drag_modified.clear();
+						} else if (tool_buttons_group->get_pressed_button() == bucket_tool_button) {
+							drag_type = DRAG_TYPE_BUCKET;
+							drag_start_mouse_pos = mpos;
+							drag_modified.clear();
+							Vector<Vector2i> line = TileMapEditor::get_line(tile_map, tile_map->world_to_map(drag_last_mouse_pos), tile_map->world_to_map(mpos));
+							for (int i = 0; i < line.size(); i++) {
+								if (!drag_modified.has(line[i])) {
+									Map<Vector2i, TileMapCell> to_draw = _draw_bucket_fill(line[i], bucket_continuous_checkbox->is_pressed());
+									for (Map<Vector2i, TileMapCell>::Element *E = to_draw.front(); E; E = E->next()) {
+										if (!erase_button->is_pressed() && E->get().source_id == -1) {
+											continue;
+										}
+										Vector2i coords = E->key();
+										if (!drag_modified.has(coords)) {
+											drag_modified.insert(coords, TileMapCell(tile_map->get_cell_source_id(coords), tile_map->get_cell_atlas_coords(coords), tile_map->get_cell_alternative_tile(coords)));
+										}
+										tile_map->set_cell(coords, E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+									}
+								}
+							}
+						}
+					}
+				}
+
+			} else {
+				// Released
+				_stop_dragging();
+			}
+
+			CanvasItemEditor::get_singleton()->update_viewport();
+
+			return true;
+		}
+		drag_last_mouse_pos = mpos;
+	}
+
+	return false;
+}
+
+void TileMapEditorTilesPlugin::forward_canvas_draw_over_viewport(Control *p_overlay) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	if (!tile_map->is_visible_in_tree()) {
+		return;
+	}
+
+	Transform2D xform = CanvasItemEditor::get_singleton()->get_canvas_transform() * tile_map->get_global_transform();
+	Vector2i tile_shape_size = tile_set->get_tile_size();
+
+	// Draw the selection.
+	if (is_visible_in_tree() && tool_buttons_group->get_pressed_button() == select_tool_button) {
+		// In select mode, we only draw the current selection if we are modifying it (pressing control or shift).
+		if (drag_type == DRAG_TYPE_MOVE || (drag_type == DRAG_TYPE_SELECT && !Input::get_singleton()->is_key_pressed(KEY_CONTROL) && !Input::get_singleton()->is_key_pressed(KEY_SHIFT))) {
+			// Do nothing
+		} else {
+			tile_map->draw_cells_outline(p_overlay, tile_map_selection, Color(0.0, 0.0, 1.0), xform);
+		}
+	}
+
+	// handle the preview of the tiles to be placed.
+	if (is_visible_in_tree() && has_mouse) { // Only if the tilemap editor is opened and the viewport is hovered.
+		Map<Vector2i, TileMapCell> preview;
+		Rect2i drawn_grid_rect;
+
+		if (drag_type == DRAG_TYPE_PICK) {
+			// Draw the area being picvked.
+			Rect2i rect = Rect2i(tile_map->world_to_map(drag_start_mouse_pos), tile_map->world_to_map(drag_last_mouse_pos) - tile_map->world_to_map(drag_start_mouse_pos)).abs();
+			rect.size += Vector2i(1, 1);
+			for (int x = rect.position.x; x < rect.get_end().x; x++) {
+				for (int y = rect.position.y; y < rect.get_end().y; y++) {
+					Vector2i coords = Vector2i(x, y);
+					if (tile_map->get_cell_source_id(coords) != -1) {
+						Rect2 cell_region = xform.xform(Rect2(tile_map->map_to_world(coords) - tile_shape_size / 2, tile_shape_size));
+						tile_set->draw_tile_shape(p_overlay, cell_region, Color(1.0, 1.0, 1.0), false);
+					}
+				}
+			}
+		} else if (drag_type == DRAG_TYPE_SELECT) {
+			// Draw the area being selected.
+			Rect2i rect = Rect2i(tile_map->world_to_map(drag_start_mouse_pos), tile_map->world_to_map(drag_last_mouse_pos) - tile_map->world_to_map(drag_start_mouse_pos)).abs();
+			rect.size += Vector2i(1, 1);
+			Set<Vector2i> to_draw;
+			for (int x = rect.position.x; x < rect.get_end().x; x++) {
+				for (int y = rect.position.y; y < rect.get_end().y; y++) {
+					Vector2i coords = Vector2i(x, y);
+					if (tile_map->get_cell_source_id(coords) != -1) {
+						to_draw.insert(coords);
+					}
+				}
+			}
+			tile_map->draw_cells_outline(p_overlay, to_draw, Color(1.0, 1.0, 1.0), xform);
+		} else if (drag_type == DRAG_TYPE_MOVE) {
+			// Preview when moving.
+			Vector2i top_left;
+			if (!tile_map_selection.is_empty()) {
+				top_left = tile_map_selection.front()->get();
+			}
+			for (Set<Vector2i>::Element *E = tile_map_selection.front(); E; E = E->next()) {
+				top_left = top_left.min(E->get());
+			}
+			Vector2i offset = drag_start_mouse_pos - tile_map->map_to_world(top_left);
+			offset = tile_map->world_to_map(drag_last_mouse_pos - offset) - tile_map->world_to_map(drag_start_mouse_pos - offset);
+
+			TypedArray<Vector2i> selection_used_cells = selection_pattern->get_used_cells();
+			for (int i = 0; i < selection_used_cells.size(); i++) {
+				Vector2i coords = tile_map->map_pattern(offset + top_left, selection_used_cells[i], selection_pattern);
+				preview[coords] = TileMapCell(selection_pattern->get_cell_source_id(selection_used_cells[i]), selection_pattern->get_cell_atlas_coords(selection_used_cells[i]), selection_pattern->get_cell_alternative_tile(selection_used_cells[i]));
+			}
+		} else if (drag_type == DRAG_TYPE_CLIPBOARD_PASTE) {
+			// Preview when pasting.
+			Vector2 mouse_offset = (Vector2(tile_map_clipboard->get_size()) / 2.0 - Vector2(0.5, 0.5)) * tile_set->get_tile_size();
+			TypedArray<Vector2i> clipboard_used_cells = tile_map_clipboard->get_used_cells();
+			for (int i = 0; i < clipboard_used_cells.size(); i++) {
+				Vector2i coords = tile_map->map_pattern(tile_map->world_to_map(drag_last_mouse_pos - mouse_offset), clipboard_used_cells[i], tile_map_clipboard);
+				preview[coords] = TileMapCell(tile_map_clipboard->get_cell_source_id(clipboard_used_cells[i]), tile_map_clipboard->get_cell_atlas_coords(clipboard_used_cells[i]), tile_map_clipboard->get_cell_alternative_tile(clipboard_used_cells[i]));
+			}
+		} else if (!picker_button->is_pressed()) {
+			bool expand_grid = false;
+			if (tool_buttons_group->get_pressed_button() == paint_tool_button && drag_type == DRAG_TYPE_NONE) {
+				// Preview for a single pattern.
+				preview = _draw_line(drag_last_mouse_pos, drag_last_mouse_pos, drag_last_mouse_pos);
+				expand_grid = true;
+			} else if (tool_buttons_group->get_pressed_button() == line_tool_button) {
+				if (drag_type == DRAG_TYPE_NONE) {
+					// Preview for a single pattern.
+					preview = _draw_line(drag_last_mouse_pos, drag_last_mouse_pos, drag_last_mouse_pos);
+					expand_grid = true;
+				} else if (drag_type == DRAG_TYPE_LINE) {
+					// Preview for a line pattern.
+					preview = _draw_line(drag_start_mouse_pos, drag_start_mouse_pos, drag_last_mouse_pos);
+					expand_grid = true;
+				}
+			} else if (tool_buttons_group->get_pressed_button() == rect_tool_button && drag_type == DRAG_TYPE_RECT) {
+				// Preview for a line pattern.
+				preview = _draw_rect(tile_map->world_to_map(drag_start_mouse_pos), tile_map->world_to_map(drag_last_mouse_pos));
+				expand_grid = true;
+			} else if (tool_buttons_group->get_pressed_button() == bucket_tool_button && drag_type == DRAG_TYPE_NONE) {
+				// Preview for a line pattern.
+				preview = _draw_bucket_fill(tile_map->world_to_map(drag_last_mouse_pos), bucket_continuous_checkbox->is_pressed());
+			}
+
+			// Expand the grid if needed
+			if (expand_grid && !preview.is_empty()) {
+				drawn_grid_rect = Rect2i(preview.front()->key(), Vector2i(1, 1));
+				for (Map<Vector2i, TileMapCell>::Element *E = preview.front(); E; E = E->next()) {
+					drawn_grid_rect.expand_to(E->key());
+				}
+			}
+		}
+
+		if (!preview.is_empty()) {
+			const int fading = 5;
+
+			// Draw the lines of the grid behind the preview.
+			if (drawn_grid_rect.size.x > 0 && drawn_grid_rect.size.y > 0) {
+				drawn_grid_rect = drawn_grid_rect.grow(fading);
+				for (int x = drawn_grid_rect.position.x; x < (drawn_grid_rect.position.x + drawn_grid_rect.size.x); x++) {
+					for (int y = drawn_grid_rect.position.y; y < (drawn_grid_rect.position.y + drawn_grid_rect.size.y); y++) {
+						Vector2i pos_in_rect = Vector2i(x, y) - drawn_grid_rect.position;
+
+						// Fade out the border of the grid.
+						float left_opacity = CLAMP(Math::inverse_lerp(0.0f, (float)fading, (float)pos_in_rect.x), 0.0f, 1.0f);
+						float right_opacity = CLAMP(Math::inverse_lerp((float)drawn_grid_rect.size.x, (float)(drawn_grid_rect.size.x - fading), (float)pos_in_rect.x), 0.0f, 1.0f);
+						float top_opacity = CLAMP(Math::inverse_lerp(0.0f, (float)fading, (float)pos_in_rect.y), 0.0f, 1.0f);
+						float bottom_opacity = CLAMP(Math::inverse_lerp((float)drawn_grid_rect.size.y, (float)(drawn_grid_rect.size.y - fading), (float)pos_in_rect.y), 0.0f, 1.0f);
+						float opacity = CLAMP(MIN(left_opacity, MIN(right_opacity, MIN(top_opacity, bottom_opacity))) + 0.1, 0.0f, 1.0f);
+
+						Rect2 cell_region = xform.xform(Rect2(tile_map->map_to_world(Vector2(x, y)) - tile_shape_size / 2, tile_shape_size));
+						tile_set->draw_tile_shape(p_overlay, cell_region, Color(1.0, 0.5, 0.2, 0.5 * opacity), false);
+					}
+				}
+			}
+
+			// Draw the preview.
+			for (Map<Vector2i, TileMapCell>::Element *E = preview.front(); E; E = E->next()) {
+				if (!erase_button->is_pressed() && random_tile_checkbox->is_pressed()) {
+					Vector2i size = tile_set->get_tile_size();
+					Vector2 position = tile_map->map_to_world(E->key()) - size / 2;
+					Rect2 cell_region = xform.xform(Rect2(position, size));
+
+					tile_set->draw_tile_shape(p_overlay, cell_region, Color(1.0, 1.0, 1.0, 0.5), true);
+				} else {
+					if (tile_set->has_source(E->get().source_id)) {
+						TileSetSource *source = *tile_set->get_source(E->get().source_id);
+						TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
+						if (atlas_source) {
+							// Get tile data.
+							TileData *tile_data = Object::cast_to<TileData>(atlas_source->get_tile_data(E->get().get_atlas_coords(), E->get().alternative_tile));
+
+							// Compute the offset
+							Rect2i source_rect = atlas_source->get_tile_texture_region(E->get().get_atlas_coords());
+							Vector2i tile_offset = atlas_source->get_tile_effective_texture_offset(E->get().get_atlas_coords(), E->get().alternative_tile);
+
+							// Compute the destination rectangle in the CanvasItem.
+							Rect2 dest_rect;
+							dest_rect.size = source_rect.size;
+
+							bool transpose = tile_data->get_transpose();
+							if (transpose) {
+								dest_rect.position = (tile_map->map_to_world(E->key()) - Vector2(dest_rect.size.y, dest_rect.size.x) / 2 - tile_offset);
+							} else {
+								dest_rect.position = (tile_map->map_to_world(E->key()) - dest_rect.size / 2 - tile_offset);
+							}
+
+							dest_rect = xform.xform(dest_rect);
+
+							if (tile_data->get_flip_h()) {
+								dest_rect.size.x = -dest_rect.size.x;
+							}
+
+							if (tile_data->get_flip_v()) {
+								dest_rect.size.y = -dest_rect.size.y;
+							}
+
+							// Get the tile modulation.
+							Color modulate = tile_data->get_modulate();
+							Color self_modulate = tile_map->get_self_modulate();
+							modulate = Color(modulate.r * self_modulate.r, modulate.g * self_modulate.g, modulate.b * self_modulate.b, modulate.a * self_modulate.a);
+
+							// Draw the tile.
+							p_overlay->draw_texture_rect_region(atlas_source->get_texture(), dest_rect, source_rect, modulate * Color(1.0, 1.0, 1.0, 0.5), transpose, tile_set->is_uv_clipping());
+						}
+					} else {
+						Vector2i size = tile_set->get_tile_size();
+						Vector2 position = tile_map->map_to_world(E->key()) - size / 2;
+						Rect2 cell_region = xform.xform(Rect2(position, size));
+
+						tile_set->draw_tile_shape(p_overlay, cell_region, Color(0.0, 0.0, 0.0, 0.5), true);
+					}
+				}
+			}
+		}
+	}
+}
+
+void TileMapEditorTilesPlugin::_mouse_exited_viewport() {
+	has_mouse = false;
+	CanvasItemEditor::get_singleton()->update_viewport();
+}
+
+TileMapCell TileMapEditorTilesPlugin::_pick_random_tile(const TileMapPattern *p_pattern) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return TileMapCell();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return TileMapCell();
+	}
+
+	TypedArray<Vector2i> used_cells = p_pattern->get_used_cells();
+	double sum = 0.0;
+	for (int i = 0; i < used_cells.size(); i++) {
+		int source_id = p_pattern->get_cell_source_id(used_cells[i]);
+		Vector2i atlas_coords = p_pattern->get_cell_atlas_coords(used_cells[i]);
+		int alternative_tile = p_pattern->get_cell_alternative_tile(used_cells[i]);
+
+		TileSetSource *source = *tile_set->get_source(source_id);
+		TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
+		if (atlas_source) {
+			sum += Object::cast_to<TileData>(atlas_source->get_tile_data(atlas_coords, alternative_tile))->get_probability();
+		} else {
+			sum += 1.0;
+		}
+	}
+
+	double empty_probability = sum * scattering;
+	double current = 0.0;
+	double rand = Math::random(0.0, sum + empty_probability);
+	for (int i = 0; i < used_cells.size(); i++) {
+		int source_id = p_pattern->get_cell_source_id(used_cells[i]);
+		Vector2i atlas_coords = p_pattern->get_cell_atlas_coords(used_cells[i]);
+		int alternative_tile = p_pattern->get_cell_alternative_tile(used_cells[i]);
+
+		TileSetSource *source = *tile_set->get_source(source_id);
+		TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
+		if (atlas_source) {
+			current += Object::cast_to<TileData>(atlas_source->get_tile_data(atlas_coords, alternative_tile))->get_probability();
+		} else {
+			current += 1.0;
+		}
+
+		if (current >= rand) {
+			return TileMapCell(source_id, atlas_coords, alternative_tile);
+		}
+	}
+	return TileMapCell();
+}
+
+Map<Vector2i, TileMapCell> TileMapEditorTilesPlugin::_draw_line(Vector2 p_start_drag_mouse_pos, Vector2 p_from_mouse_pos, Vector2i p_to_mouse_pos) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return Map<Vector2i, TileMapCell>();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return Map<Vector2i, TileMapCell>();
+	}
+
+	// Get or create the pattern.
+	TileMapPattern erase_pattern;
+	erase_pattern.set_cell(Vector2i(0, 0), -1, TileSetAtlasSource::INVALID_ATLAS_COORDS, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+	TileMapPattern *pattern = erase_button->is_pressed() ? &erase_pattern : selection_pattern;
+
+	Map<Vector2i, TileMapCell> output;
+	if (!pattern->is_empty()) {
+		// Paint the tiles on the tile map.
+		if (!erase_button->is_pressed() && random_tile_checkbox->is_pressed()) {
+			// Paint a random tile.
+			Vector<Vector2i> line = TileMapEditor::get_line(tile_map, tile_map->world_to_map(p_from_mouse_pos), tile_map->world_to_map(p_to_mouse_pos));
+			for (int i = 0; i < line.size(); i++) {
+				output.insert(line[i], _pick_random_tile(pattern));
+			}
+		} else {
+			// Paint the pattern.
+			// If we paint several tiles, we virtually move the mouse as if it was in the center of the "brush"
+			Vector2 mouse_offset = (Vector2(pattern->get_size()) / 2.0 - Vector2(0.5, 0.5)) * tile_set->get_tile_size();
+			Vector2i last_hovered_cell = tile_map->world_to_map(p_from_mouse_pos - mouse_offset);
+			Vector2i new_hovered_cell = tile_map->world_to_map(p_to_mouse_pos - mouse_offset);
+			Vector2i drag_start_cell = tile_map->world_to_map(p_start_drag_mouse_pos - mouse_offset);
+
+			TypedArray<Vector2i> used_cells = pattern->get_used_cells();
+			Vector2i offset = Vector2i(Math::posmod(drag_start_cell.x, pattern->get_size().x), Math::posmod(drag_start_cell.y, pattern->get_size().y)); // Note: no posmodv for Vector2i for now. Meh.s
+			Vector<Vector2i> line = TileMapEditor::get_line(tile_map, (last_hovered_cell - offset) / pattern->get_size(), (new_hovered_cell - offset) / pattern->get_size());
+			for (int i = 0; i < line.size(); i++) {
+				Vector2i top_left = line[i] * pattern->get_size() + offset;
+				for (int j = 0; j < used_cells.size(); j++) {
+					Vector2i coords = tile_map->map_pattern(top_left, used_cells[j], pattern);
+					output.insert(coords, TileMapCell(pattern->get_cell_source_id(used_cells[j]), pattern->get_cell_atlas_coords(used_cells[j]), pattern->get_cell_alternative_tile(used_cells[j])));
+				}
+			}
+		}
+	}
+	return output;
+}
+
+Map<Vector2i, TileMapCell> TileMapEditorTilesPlugin::_draw_rect(Vector2i p_start_cell, Vector2i p_end_cell) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return Map<Vector2i, TileMapCell>();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return Map<Vector2i, TileMapCell>();
+	}
+
+	// Create the rect to draw.
+	Rect2i rect = Rect2i(p_start_cell, p_end_cell - p_start_cell).abs();
+	rect.size += Vector2i(1, 1);
+
+	// Get or create the pattern.
+	TileMapPattern erase_pattern;
+	erase_pattern.set_cell(Vector2i(0, 0), -1, TileSetAtlasSource::INVALID_ATLAS_COORDS, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+	TileMapPattern *pattern = erase_button->is_pressed() ? &erase_pattern : selection_pattern;
+
+	// Compute the offset to align things to the bottom or right.
+	bool aligned_right = p_end_cell.x < p_start_cell.x;
+	bool valigned_bottom = p_end_cell.y < p_start_cell.y;
+	Vector2i offset = Vector2i(aligned_right ? -(pattern->get_size().x - (rect.get_size().x % pattern->get_size().x)) : 0, valigned_bottom ? -(pattern->get_size().y - (rect.get_size().y % pattern->get_size().y)) : 0);
+
+	Map<Vector2i, TileMapCell> output;
+	if (!pattern->is_empty()) {
+		if (!erase_button->is_pressed() && random_tile_checkbox->is_pressed()) {
+			// Paint a random tile.
+			for (int x = 0; x < rect.size.x; x++) {
+				for (int y = 0; y < rect.size.y; y++) {
+					Vector2i coords = rect.position + Vector2i(x, y);
+					output.insert(coords, _pick_random_tile(pattern));
+				}
+			}
+		} else {
+			// Paint the pattern.
+			TypedArray<Vector2i> used_cells = pattern->get_used_cells();
+			for (int x = 0; x <= rect.size.x / pattern->get_size().x; x++) {
+				for (int y = 0; y <= rect.size.y / pattern->get_size().y; y++) {
+					Vector2i pattern_coords = rect.position + Vector2i(x, y) * pattern->get_size() + offset;
+					for (int j = 0; j < used_cells.size(); j++) {
+						Vector2i coords = pattern_coords + used_cells[j];
+						if (rect.has_point(coords)) {
+							output.insert(coords, TileMapCell(pattern->get_cell_source_id(used_cells[j]), pattern->get_cell_atlas_coords(used_cells[j]), pattern->get_cell_alternative_tile(used_cells[j])));
+						}
+					}
+				}
+			}
+		}
+	}
+
+	return output;
+}
+
+Map<Vector2i, TileMapCell> TileMapEditorTilesPlugin::_draw_bucket_fill(Vector2i p_coords, bool p_contiguous) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return Map<Vector2i, TileMapCell>();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return Map<Vector2i, TileMapCell>();
+	}
+
+	// Get or create the pattern.
+	TileMapPattern erase_pattern;
+	erase_pattern.set_cell(Vector2i(0, 0), -1, TileSetAtlasSource::INVALID_ATLAS_COORDS, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+	TileMapPattern *pattern = erase_button->is_pressed() ? &erase_pattern : selection_pattern;
+
+	Map<Vector2i, TileMapCell> output;
+	if (!pattern->is_empty()) {
+		TileMapCell source = tile_map->get_cell(p_coords);
+
+		// If we are filling empty tiles, compute the tilemap boundaries.
+		Rect2i boundaries;
+		if (source.source_id == -1) {
+			boundaries = tile_map->get_used_rect();
+		}
+
+		if (p_contiguous) {
+			// Replace continuous tiles like the source.
+			Set<Vector2i> already_checked;
+			List<Vector2i> to_check;
+			to_check.push_back(p_coords);
+			while (!to_check.is_empty()) {
+				Vector2i coords = to_check.back()->get();
+				to_check.pop_back();
+				if (!already_checked.has(coords)) {
+					if (source.source_id == tile_map->get_cell_source_id(coords) &&
+							source.get_atlas_coords() == tile_map->get_cell_atlas_coords(coords) &&
+							source.alternative_tile == tile_map->get_cell_alternative_tile(coords) &&
+							(source.source_id != -1 || boundaries.has_point(coords))) {
+						if (!erase_button->is_pressed() && random_tile_checkbox->is_pressed()) {
+							// Paint a random tile.
+							output.insert(coords, _pick_random_tile(pattern));
+						} else {
+							// Paint the pattern.
+							Vector2i pattern_coords = (coords - p_coords) % pattern->get_size(); // Note: it would be good to have posmodv for Vector2i.
+							pattern_coords.x = pattern_coords.x < 0 ? pattern_coords.x + pattern->get_size().x : pattern_coords.x;
+							pattern_coords.y = pattern_coords.y < 0 ? pattern_coords.y + pattern->get_size().y : pattern_coords.y;
+							if (pattern->has_cell(pattern_coords)) {
+								output.insert(coords, TileMapCell(pattern->get_cell_source_id(pattern_coords), pattern->get_cell_atlas_coords(pattern_coords), pattern->get_cell_alternative_tile(pattern_coords)));
+							} else {
+								output.insert(coords, TileMapCell());
+							}
+						}
+
+						// Get surrounding tiles (handles different tile shapes).
+						TypedArray<Vector2i> around = tile_map->get_surrounding_tiles(coords);
+						for (int i = 0; i < around.size(); i++) {
+							to_check.push_back(around[i]);
+						}
+					}
+					already_checked.insert(coords);
+				}
+			}
+		} else {
+			// Replace all tiles like the source.
+			TypedArray<Vector2i> to_check;
+			if (source.source_id == -1) {
+				Rect2i rect = tile_map->get_used_rect();
+				if (rect.size.x <= 0 || rect.size.y <= 0) {
+					rect = Rect2i(p_coords, Vector2i(1, 1));
+				}
+				for (int x = boundaries.position.x; x < boundaries.get_end().x; x++) {
+					for (int y = boundaries.position.y; y < boundaries.get_end().y; y++) {
+						to_check.append(Vector2i(x, y));
+					}
+				}
+			} else {
+				to_check = tile_map->get_used_cells();
+			}
+			for (int i = 0; i < to_check.size(); i++) {
+				Vector2i coords = to_check[i];
+				if (source.source_id == tile_map->get_cell_source_id(coords) &&
+						source.get_atlas_coords() == tile_map->get_cell_atlas_coords(coords) &&
+						source.alternative_tile == tile_map->get_cell_alternative_tile(coords) &&
+						(source.source_id != -1 || boundaries.has_point(coords))) {
+					if (!erase_button->is_pressed() && random_tile_checkbox->is_pressed()) {
+						// Paint a random tile.
+						output.insert(coords, _pick_random_tile(pattern));
+					} else {
+						// Paint the pattern.
+						Vector2i pattern_coords = (coords - p_coords) % pattern->get_size(); // Note: it would be good to have posmodv for Vector2i.
+						pattern_coords.x = pattern_coords.x < 0 ? pattern_coords.x + pattern->get_size().x : pattern_coords.x;
+						pattern_coords.y = pattern_coords.y < 0 ? pattern_coords.y + pattern->get_size().y : pattern_coords.y;
+						if (pattern->has_cell(pattern_coords)) {
+							output.insert(coords, TileMapCell(pattern->get_cell_source_id(pattern_coords), pattern->get_cell_atlas_coords(pattern_coords), pattern->get_cell_alternative_tile(pattern_coords)));
+						} else {
+							output.insert(coords, TileMapCell());
+						}
+					}
+				}
+			}
+		}
+	}
+	return output;
+}
+
+void TileMapEditorTilesPlugin::_stop_dragging() {
+	if (drag_type == DRAG_TYPE_NONE) {
+		return;
+	}
+
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	Transform2D xform = CanvasItemEditor::get_singleton()->get_canvas_transform() * tile_map->get_global_transform();
+	Vector2 mpos = xform.affine_inverse().xform(CanvasItemEditor::get_singleton()->get_viewport_control()->get_local_mouse_position());
+
+	switch (drag_type) {
+		case DRAG_TYPE_SELECT: {
+			undo_redo->create_action(TTR("Change selection"));
+			undo_redo->add_undo_method(this, "_set_tile_map_selection", _get_tile_map_selection());
+
+			if (!Input::get_singleton()->is_key_pressed(KEY_SHIFT) && !Input::get_singleton()->is_key_pressed(KEY_CONTROL)) {
+				tile_map_selection.clear();
+			}
+			Rect2i rect = Rect2i(tile_map->world_to_map(drag_start_mouse_pos), tile_map->world_to_map(mpos) - tile_map->world_to_map(drag_start_mouse_pos)).abs();
+			for (int x = rect.position.x; x <= rect.get_end().x; x++) {
+				for (int y = rect.position.y; y <= rect.get_end().y; y++) {
+					Vector2i coords = Vector2i(x, y);
+					if (Input::get_singleton()->is_key_pressed(KEY_CONTROL)) {
+						if (tile_map_selection.has(coords)) {
+							tile_map_selection.erase(coords);
+						}
+					} else {
+						if (tile_map->get_cell_source_id(coords) != -1) {
+							tile_map_selection.insert(coords);
+						}
+					}
+				}
+			}
+			undo_redo->add_do_method(this, "_set_tile_map_selection", _get_tile_map_selection());
+			undo_redo->commit_action(false);
+
+			_update_selection_pattern_from_tilemap_selection();
+			_update_tileset_selection_from_selection_pattern();
+		} break;
+		case DRAG_TYPE_MOVE: {
+			Vector2i top_left;
+			if (!tile_map_selection.is_empty()) {
+				top_left = tile_map_selection.front()->get();
+			}
+			for (Set<Vector2i>::Element *E = tile_map_selection.front(); E; E = E->next()) {
+				top_left = top_left.min(E->get());
+			}
+
+			Vector2i offset = drag_start_mouse_pos - tile_map->map_to_world(top_left);
+			offset = tile_map->world_to_map(mpos - offset) - tile_map->world_to_map(drag_start_mouse_pos - offset);
+
+			TypedArray<Vector2i> selection_used_cells = selection_pattern->get_used_cells();
+
+			Vector2i coords;
+			Map<Vector2i, TileMapCell> cells_undo;
+			for (int i = 0; i < selection_used_cells.size(); i++) {
+				coords = tile_map->map_pattern(top_left, selection_used_cells[i], selection_pattern);
+				cells_undo[coords] = TileMapCell(drag_modified[coords].source_id, drag_modified[coords].get_atlas_coords(), drag_modified[coords].alternative_tile);
+				coords = tile_map->map_pattern(top_left + offset, selection_used_cells[i], selection_pattern);
+				cells_undo[coords] = TileMapCell(tile_map->get_cell_source_id(coords), tile_map->get_cell_atlas_coords(coords), tile_map->get_cell_alternative_tile(coords));
+			}
+
+			Map<Vector2i, TileMapCell> cells_do;
+			for (int i = 0; i < selection_used_cells.size(); i++) {
+				coords = tile_map->map_pattern(top_left, selection_used_cells[i], selection_pattern);
+				cells_do[coords] = TileMapCell();
+			}
+			for (int i = 0; i < selection_used_cells.size(); i++) {
+				coords = tile_map->map_pattern(top_left + offset, selection_used_cells[i], selection_pattern);
+				cells_do[coords] = TileMapCell(selection_pattern->get_cell_source_id(selection_used_cells[i]), selection_pattern->get_cell_atlas_coords(selection_used_cells[i]), selection_pattern->get_cell_alternative_tile(selection_used_cells[i]));
+			}
+			undo_redo->create_action(TTR("Move tiles"));
+			// Move the tiles.
+			for (Map<Vector2i, TileMapCell>::Element *E = cells_do.front(); E; E = E->next()) {
+				undo_redo->add_do_method(tile_map, "set_cell", E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+			}
+			for (Map<Vector2i, TileMapCell>::Element *E = cells_undo.front(); E; E = E->next()) {
+				undo_redo->add_undo_method(tile_map, "set_cell", E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+			}
+
+			// Update the selection.
+			undo_redo->add_undo_method(this, "_set_tile_map_selection", _get_tile_map_selection());
+			tile_map_selection.clear();
+			for (int i = 0; i < selection_used_cells.size(); i++) {
+				coords = tile_map->map_pattern(top_left + offset, selection_used_cells[i], selection_pattern);
+				tile_map_selection.insert(coords);
+			}
+			undo_redo->add_do_method(this, "_set_tile_map_selection", _get_tile_map_selection());
+			undo_redo->commit_action();
+		} break;
+		case DRAG_TYPE_PICK: {
+			Rect2i rect = Rect2i(tile_map->world_to_map(drag_start_mouse_pos), tile_map->world_to_map(mpos) - tile_map->world_to_map(drag_start_mouse_pos)).abs();
+			rect.size += Vector2i(1, 1);
+			memdelete(selection_pattern);
+			TypedArray<Vector2i> coords_array;
+			for (int x = rect.position.x; x < rect.get_end().x; x++) {
+				for (int y = rect.position.y; y < rect.get_end().y; y++) {
+					Vector2i coords = Vector2i(x, y);
+					if (tile_map->get_cell_source_id(coords) != -1) {
+						coords_array.push_back(coords);
+					}
+				}
+			}
+			selection_pattern = tile_map->get_pattern(coords_array);
+			if (!selection_pattern->is_empty()) {
+				_update_tileset_selection_from_selection_pattern();
+			} else {
+				_update_selection_pattern_from_tileset_selection();
+			}
+			picker_button->set_pressed(false);
+		} break;
+		case DRAG_TYPE_PAINT: {
+			undo_redo->create_action(TTR("Paint tiles"));
+			for (Map<Vector2i, TileMapCell>::Element *E = drag_modified.front(); E; E = E->next()) {
+				undo_redo->add_do_method(tile_map, "set_cell", E->key(), tile_map->get_cell_source_id(E->key()), tile_map->get_cell_atlas_coords(E->key()), tile_map->get_cell_alternative_tile(E->key()));
+				undo_redo->add_undo_method(tile_map, "set_cell", E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+			}
+			undo_redo->commit_action(false);
+		} break;
+		case DRAG_TYPE_LINE: {
+			Map<Vector2i, TileMapCell> to_draw = _draw_line(drag_start_mouse_pos, drag_start_mouse_pos, mpos);
+			undo_redo->create_action(TTR("Paint tiles"));
+			for (Map<Vector2i, TileMapCell>::Element *E = to_draw.front(); E; E = E->next()) {
+				if (!erase_button->is_pressed() && E->get().source_id == -1) {
+					continue;
+				}
+				undo_redo->add_do_method(tile_map, "set_cell", E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+				undo_redo->add_undo_method(tile_map, "set_cell", E->key(), tile_map->get_cell_source_id(E->key()), tile_map->get_cell_atlas_coords(E->key()), tile_map->get_cell_alternative_tile(E->key()));
+			}
+			undo_redo->commit_action();
+		} break;
+		case DRAG_TYPE_RECT: {
+			Map<Vector2i, TileMapCell> to_draw = _draw_rect(tile_map->world_to_map(drag_start_mouse_pos), tile_map->world_to_map(mpos));
+			undo_redo->create_action(TTR("Paint tiles"));
+			for (Map<Vector2i, TileMapCell>::Element *E = to_draw.front(); E; E = E->next()) {
+				if (!erase_button->is_pressed() && E->get().source_id == -1) {
+					continue;
+				}
+				undo_redo->add_do_method(tile_map, "set_cell", E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+				undo_redo->add_undo_method(tile_map, "set_cell", E->key(), tile_map->get_cell_source_id(E->key()), tile_map->get_cell_atlas_coords(E->key()), tile_map->get_cell_alternative_tile(E->key()));
+			}
+			undo_redo->commit_action();
+		} break;
+		case DRAG_TYPE_BUCKET: {
+			undo_redo->create_action(TTR("Paint tiles"));
+			for (Map<Vector2i, TileMapCell>::Element *E = drag_modified.front(); E; E = E->next()) {
+				if (!erase_button->is_pressed() && E->get().source_id == -1) {
+					continue;
+				}
+				undo_redo->add_do_method(tile_map, "set_cell", E->key(), tile_map->get_cell_source_id(E->key()), tile_map->get_cell_atlas_coords(E->key()), tile_map->get_cell_alternative_tile(E->key()));
+				undo_redo->add_undo_method(tile_map, "set_cell", E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+			}
+			undo_redo->commit_action(false);
+		} break;
+		case DRAG_TYPE_CLIPBOARD_PASTE: {
+			Vector2 mouse_offset = (Vector2(tile_map_clipboard->get_size()) / 2.0 - Vector2(0.5, 0.5)) * tile_set->get_tile_size();
+			undo_redo->create_action(TTR("Paste tiles"));
+			TypedArray<Vector2i> used_cells = tile_map_clipboard->get_used_cells();
+			for (int i = 0; i < used_cells.size(); i++) {
+				Vector2i coords = tile_map->map_pattern(tile_map->world_to_map(mpos - mouse_offset), used_cells[i], tile_map_clipboard);
+				undo_redo->add_do_method(tile_map, "set_cell", coords, tile_map_clipboard->get_cell_source_id(used_cells[i]), tile_map_clipboard->get_cell_atlas_coords(used_cells[i]), tile_map_clipboard->get_cell_alternative_tile(used_cells[i]));
+				undo_redo->add_undo_method(tile_map, "set_cell", coords, tile_map->get_cell_source_id(coords), tile_map->get_cell_atlas_coords(coords), tile_map->get_cell_alternative_tile(coords));
+			}
+			undo_redo->commit_action();
+		} break;
+		default:
+			break;
+	}
+	drag_type = DRAG_TYPE_NONE;
+}
+
+void TileMapEditorTilesPlugin::_update_fix_selected_and_hovered() {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		hovered_tile.source_id = -1;
+		hovered_tile.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+		hovered_tile.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+		tile_set_selection.clear();
+		tile_map_selection.clear();
+		selection_pattern->clear();
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		hovered_tile.source_id = -1;
+		hovered_tile.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+		hovered_tile.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+		tile_set_selection.clear();
+		tile_map_selection.clear();
+		selection_pattern->clear();
+		return;
+	}
+
+	int source_index = sources_list->get_current();
+	if (source_index < 0 || source_index >= sources_list->get_item_count()) {
+		hovered_tile.source_id = -1;
+		hovered_tile.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+		hovered_tile.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+		tile_set_selection.clear();
+		tile_map_selection.clear();
+		selection_pattern->clear();
+		return;
+	}
+
+	int source_id = sources_list->get_item_metadata(source_index);
+
+	// Clear hovered if needed.
+	if (source_id != hovered_tile.source_id ||
+			!tile_set->has_source(hovered_tile.source_id) ||
+			!tile_set->get_source(hovered_tile.source_id)->has_tile(hovered_tile.get_atlas_coords()) ||
+			!tile_set->get_source(hovered_tile.source_id)->has_alternative_tile(hovered_tile.get_atlas_coords(), hovered_tile.alternative_tile)) {
+		hovered_tile.source_id = -1;
+		hovered_tile.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+		hovered_tile.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+	}
+
+	// Selection if needed.
+	for (Set<TileMapCell>::Element *E = tile_set_selection.front(); E; E = E->next()) {
+		const TileMapCell *selected = &(E->get());
+		if (!tile_set->has_source(selected->source_id) ||
+				!tile_set->get_source(selected->source_id)->has_tile(selected->get_atlas_coords()) ||
+				!tile_set->get_source(selected->source_id)->has_alternative_tile(selected->get_atlas_coords(), selected->alternative_tile)) {
+			tile_set_selection.erase(E);
+		}
+	}
+
+	if (!tile_map_selection.is_empty()) {
+		_update_selection_pattern_from_tilemap_selection();
+	} else {
+		_update_selection_pattern_from_tileset_selection();
+	}
+}
+
+void TileMapEditorTilesPlugin::_update_selection_pattern_from_tilemap_selection() {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	memdelete(selection_pattern);
+
+	TypedArray<Vector2i> coords_array;
+	for (Set<Vector2i>::Element *E = tile_map_selection.front(); E; E = E->next()) {
+		coords_array.push_back(E->get());
+	}
+	selection_pattern = tile_map->get_pattern(coords_array);
+}
+
+void TileMapEditorTilesPlugin::_update_selection_pattern_from_tileset_selection() {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	// Clear the tilemap selection.
+	tile_map_selection.clear();
+
+	// Clear the selected pattern.
+	selection_pattern->clear();
+
+	// Group per source.
+	Map<int, List<const TileMapCell *>> per_source;
+	for (Set<TileMapCell>::Element *E = tile_set_selection.front(); E; E = E->next()) {
+		per_source[E->get().source_id].push_back(&(E->get()));
+	}
+
+	for (Map<int, List<const TileMapCell *>>::Element *E_source = per_source.front(); E_source; E_source = E_source->next()) {
+		// Per source.
+		List<const TileMapCell *> unorganized;
+		Rect2i encompassing_rect_coords;
+		Map<Vector2i, const TileMapCell *> organized_pattern;
+
+		TileSetSource *source = *tile_set->get_source(E_source->key());
+		TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
+		if (atlas_source) {
+			// Organize using coordinates.
+			for (List<const TileMapCell *>::Element *E_cell = E_source->get().front(); E_cell; E_cell = E_cell->next()) {
+				const TileMapCell *current = E_cell->get();
+				if (organized_pattern.has(current->get_atlas_coords())) {
+					if (current->alternative_tile < organized_pattern[current->get_atlas_coords()]->alternative_tile) {
+						unorganized.push_back(organized_pattern[current->get_atlas_coords()]);
+						organized_pattern[current->get_atlas_coords()] = current;
+					} else {
+						unorganized.push_back(current);
+					}
+				} else {
+					organized_pattern[current->get_atlas_coords()] = current;
+				}
+			}
+
+			// Compute the encompassing rect for the organized pattern.
+			Map<Vector2i, const TileMapCell *>::Element *E_cell = organized_pattern.front();
+			encompassing_rect_coords = Rect2i(E_cell->key(), Vector2i(1, 1));
+			for (; E_cell; E_cell = E_cell->next()) {
+				encompassing_rect_coords.expand_to(E_cell->key() + Vector2i(1, 1));
+				encompassing_rect_coords.expand_to(E_cell->key());
+			}
+		} else {
+			// Add everything unorganized.
+			for (List<const TileMapCell *>::Element *E_cell = E_source->get().front(); E_cell; E_cell = E_cell->next()) {
+				unorganized.push_back(E_cell->get());
+			}
+		}
+
+		// Now add everything to the output pattern.
+		for (Map<Vector2i, const TileMapCell *>::Element *E_cell = organized_pattern.front(); E_cell; E_cell = E_cell->next()) {
+			selection_pattern->set_cell(E_cell->key() - encompassing_rect_coords.position, E_cell->get()->source_id, E_cell->get()->get_atlas_coords(), E_cell->get()->alternative_tile);
+		}
+		Vector2i organized_size = selection_pattern->get_size();
+		for (List<const TileMapCell *>::Element *E_cell = unorganized.front(); E_cell; E_cell = E_cell->next()) {
+			selection_pattern->set_cell(Vector2(organized_size.x, 0), E_cell->get()->source_id, E_cell->get()->get_atlas_coords(), E_cell->get()->alternative_tile);
+		}
+	}
+	CanvasItemEditor::get_singleton()->update_viewport();
+}
+
+void TileMapEditorTilesPlugin::_update_tileset_selection_from_selection_pattern() {
+	tile_set_selection.clear();
+	TypedArray<Vector2i> used_cells = selection_pattern->get_used_cells();
+	for (int i = 0; i < used_cells.size(); i++) {
+		Vector2i coords = used_cells[i];
+		if (selection_pattern->get_cell_source_id(coords) != -1) {
+			tile_set_selection.insert(TileMapCell(selection_pattern->get_cell_source_id(coords), selection_pattern->get_cell_atlas_coords(coords), selection_pattern->get_cell_alternative_tile(coords)));
+		}
+	}
+	_update_atlas_view();
+}
+
+void TileMapEditorTilesPlugin::_tile_atlas_control_draw() {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	int source_index = sources_list->get_current();
+	if (source_index < 0 || source_index >= sources_list->get_item_count()) {
+		return;
+	}
+
+	int source_id = sources_list->get_item_metadata(source_index);
+	if (!tile_set->has_source(source_id)) {
+		return;
+	}
+
+	TileSetAtlasSource *atlas = Object::cast_to<TileSetAtlasSource>(*tile_set->get_source(source_id));
+	if (!atlas) {
+		return;
+	}
+
+	// Draw the selection.
+	for (Set<TileMapCell>::Element *E = tile_set_selection.front(); E; E = E->next()) {
+		if (E->get().source_id == source_id && E->get().alternative_tile == 0) {
+			tile_atlas_control->draw_rect(atlas->get_tile_texture_region(E->get().get_atlas_coords()), Color(0.0, 0.0, 1.0), false);
+		}
+	}
+
+	// Draw the hovered tile.
+	if (hovered_tile.get_atlas_coords() != TileSetAtlasSource::INVALID_ATLAS_COORDS && hovered_tile.alternative_tile == 0 && !tile_set_dragging_selection) {
+		tile_atlas_control->draw_rect(atlas->get_tile_texture_region(hovered_tile.get_atlas_coords()), Color(1.0, 1.0, 1.0), false);
+	}
+
+	// Draw the selection rect.
+	if (tile_set_dragging_selection) {
+		Vector2i start_tile = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_set_drag_start_mouse_pos);
+		Vector2i end_tile = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+
+		Rect2i region = Rect2i(start_tile, end_tile - start_tile).abs();
+		region.size += Vector2i(1, 1);
+
+		Set<Vector2i> to_draw;
+		for (int x = region.position.x; x < region.get_end().x; x++) {
+			for (int y = region.position.y; y < region.get_end().y; y++) {
+				Vector2i tile = atlas->get_tile_at_coords(Vector2i(x, y));
+				if (tile != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					to_draw.insert(tile);
+				}
+			}
+		}
+
+		for (Set<Vector2i>::Element *E = to_draw.front(); E; E = E->next()) {
+			tile_atlas_control->draw_rect(atlas->get_tile_texture_region(E->get()), Color(0.8, 0.8, 1.0), false);
+		}
+	}
+}
+
+void TileMapEditorTilesPlugin::_tile_atlas_control_mouse_exited() {
+	hovered_tile.source_id = -1;
+	hovered_tile.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+	hovered_tile.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+	tile_set_dragging_selection = false;
+	tile_atlas_control->update();
+}
+
+void TileMapEditorTilesPlugin::_tile_atlas_control_gui_input(const Ref<InputEvent> &p_event) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	int source_index = sources_list->get_current();
+	if (source_index < 0 || source_index >= sources_list->get_item_count()) {
+		return;
+	}
+
+	int source_id = sources_list->get_item_metadata(source_index);
+	if (!tile_set->has_source(source_id)) {
+		return;
+	}
+
+	TileSetAtlasSource *atlas = Object::cast_to<TileSetAtlasSource>(*tile_set->get_source(source_id));
+	if (!atlas) {
+		return;
+	}
+
+	// Update the hovered tile
+	hovered_tile.source_id = source_id;
+	hovered_tile.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+	hovered_tile.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+	Vector2i coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+	if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+		coords = atlas->get_tile_at_coords(coords);
+		if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+			hovered_tile.set_atlas_coords(coords);
+			hovered_tile.alternative_tile = 0;
+		}
+	}
+
+	Ref<InputEventMouseMotion> mm = p_event;
+	if (mm.is_valid()) {
+		tile_atlas_control->update();
+		alternative_tiles_control->update();
+	}
+
+	Ref<InputEventMouseButton> mb = p_event;
+	if (mb.is_valid() && mb->get_button_index() == MOUSE_BUTTON_LEFT) {
+		if (mb->is_pressed()) { // Pressed
+			tile_set_dragging_selection = true;
+			tile_set_drag_start_mouse_pos = tile_atlas_control->get_local_mouse_position();
+			if (!mb->get_shift()) {
+				tile_set_selection.clear();
+			}
+
+			if (hovered_tile.get_atlas_coords() != TileSetAtlasSource::INVALID_ATLAS_COORDS && hovered_tile.alternative_tile == 0) {
+				if (mb->get_shift() && tile_set_selection.has(TileMapCell(source_id, hovered_tile.get_atlas_coords(), 0))) {
+					tile_set_selection.erase(TileMapCell(source_id, hovered_tile.get_atlas_coords(), 0));
+				} else {
+					tile_set_selection.insert(TileMapCell(source_id, hovered_tile.get_atlas_coords(), 0));
+				}
+			}
+			_update_selection_pattern_from_tileset_selection();
+		} else { // Released
+			if (tile_set_dragging_selection) {
+				if (!mb->get_shift()) {
+					tile_set_selection.clear();
+				}
+				// Compute the covered area.
+				Vector2i start_tile = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_set_drag_start_mouse_pos);
+				Vector2i end_tile = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+				if (start_tile != TileSetAtlasSource::INVALID_ATLAS_COORDS && end_tile != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					Rect2i region = Rect2i(start_tile, end_tile - start_tile).abs();
+					region.size += Vector2i(1, 1);
+
+					// To update the selection, we copy the selected/not selected status of the tiles we drag from.
+					Vector2i start_coords = atlas->get_tile_at_coords(start_tile);
+					if (mb->get_shift() && start_coords != TileSetAtlasSource::INVALID_ATLAS_COORDS && !tile_set_selection.has(TileMapCell(source_id, start_coords, 0))) {
+						// Remove from the selection.
+						for (int x = region.position.x; x < region.get_end().x; x++) {
+							for (int y = region.position.y; y < region.get_end().y; y++) {
+								Vector2i tile_coords = atlas->get_tile_at_coords(Vector2i(x, y));
+								if (tile_coords != TileSetAtlasSource::INVALID_ATLAS_COORDS && tile_set_selection.has(TileMapCell(source_id, tile_coords, 0))) {
+									tile_set_selection.erase(TileMapCell(source_id, tile_coords, 0));
+								}
+							}
+						}
+					} else {
+						// Insert in the selection.
+						for (int x = region.position.x; x < region.get_end().x; x++) {
+							for (int y = region.position.y; y < region.get_end().y; y++) {
+								Vector2i tile_coords = atlas->get_tile_at_coords(Vector2i(x, y));
+								if (tile_coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+									tile_set_selection.insert(TileMapCell(source_id, tile_coords, 0));
+								}
+							}
+						}
+					}
+				}
+				_update_selection_pattern_from_tileset_selection();
+			}
+			tile_set_dragging_selection = false;
+		}
+		tile_atlas_control->update();
+	}
+}
+
+void TileMapEditorTilesPlugin::_tile_alternatives_control_draw() {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	int source_index = sources_list->get_current();
+	if (source_index < 0 || source_index >= sources_list->get_item_count()) {
+		return;
+	}
+
+	int source_id = sources_list->get_item_metadata(source_index);
+	if (!tile_set->has_source(source_id)) {
+		return;
+	}
+
+	TileSetAtlasSource *atlas = Object::cast_to<TileSetAtlasSource>(*tile_set->get_source(source_id));
+	if (!atlas) {
+		return;
+	}
+
+	// Draw the selection.
+	for (Set<TileMapCell>::Element *E = tile_set_selection.front(); E; E = E->next()) {
+		if (E->get().source_id == source_id && E->get().get_atlas_coords() != TileSetAtlasSource::INVALID_ATLAS_COORDS && E->get().alternative_tile > 0) {
+			Rect2i rect = tile_atlas_view->get_alternative_tile_rect(E->get().get_atlas_coords(), E->get().alternative_tile);
+			if (rect != Rect2i()) {
+				alternative_tiles_control->draw_rect(rect, Color(0.2, 0.2, 1.0), false);
+			}
+		}
+	}
+
+	// Draw hovered tile.
+	if (hovered_tile.get_atlas_coords() != TileSetAtlasSource::INVALID_ATLAS_COORDS && hovered_tile.alternative_tile > 0) {
+		Rect2i rect = tile_atlas_view->get_alternative_tile_rect(hovered_tile.get_atlas_coords(), hovered_tile.alternative_tile);
+		if (rect != Rect2i()) {
+			alternative_tiles_control->draw_rect(rect, Color(1.0, 1.0, 1.0), false);
+		}
+	}
+}
+
+void TileMapEditorTilesPlugin::_tile_alternatives_control_mouse_exited() {
+	hovered_tile.source_id = -1;
+	hovered_tile.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+	hovered_tile.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+	tile_set_dragging_selection = false;
+	alternative_tiles_control->update();
+}
+
+void TileMapEditorTilesPlugin::_tile_alternatives_control_gui_input(const Ref<InputEvent> &p_event) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	int source_index = sources_list->get_current();
+	if (source_index < 0 || source_index >= sources_list->get_item_count()) {
+		return;
+	}
+
+	int source_id = sources_list->get_item_metadata(source_index);
+	if (!tile_set->has_source(source_id)) {
+		return;
+	}
+
+	TileSetAtlasSource *atlas = Object::cast_to<TileSetAtlasSource>(*tile_set->get_source(source_id));
+	if (!atlas) {
+		return;
+	}
+
+	// Update the hovered tile
+	hovered_tile.source_id = source_id;
+	hovered_tile.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+	hovered_tile.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+	Vector3i alternative_coords = tile_atlas_view->get_alternative_tile_at_pos(alternative_tiles_control->get_local_mouse_position());
+	Vector2i coords = Vector2i(alternative_coords.x, alternative_coords.y);
+	int alternative = alternative_coords.z;
+	if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS && alternative != TileSetAtlasSource::INVALID_TILE_ALTERNATIVE) {
+		hovered_tile.set_atlas_coords(coords);
+		hovered_tile.alternative_tile = alternative;
+	}
+
+	Ref<InputEventMouseMotion> mm = p_event;
+	if (mm.is_valid()) {
+		tile_atlas_control->update();
+		alternative_tiles_control->update();
+	}
+
+	Ref<InputEventMouseButton> mb = p_event;
+	if (mb.is_valid() && mb->get_button_index() == MOUSE_BUTTON_LEFT) {
+		if (mb->is_pressed()) { // Pressed
+			// Left click pressed.
+			if (!mb->get_shift()) {
+				tile_set_selection.clear();
+			}
+
+			if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS && alternative != TileSetAtlasSource::INVALID_TILE_ALTERNATIVE) {
+				if (mb->get_shift() && tile_set_selection.has(TileMapCell(source_id, hovered_tile.get_atlas_coords(), hovered_tile.alternative_tile))) {
+					tile_set_selection.erase(TileMapCell(source_id, hovered_tile.get_atlas_coords(), hovered_tile.alternative_tile));
+				} else {
+					tile_set_selection.insert(TileMapCell(source_id, hovered_tile.get_atlas_coords(), hovered_tile.alternative_tile));
+				}
+			}
+			_update_selection_pattern_from_tileset_selection();
+		}
+		tile_atlas_control->update();
+		alternative_tiles_control->update();
+	}
+}
+
+void TileMapEditorTilesPlugin::_set_tile_map_selection(const TypedArray<Vector2i> &p_selection) {
+	tile_map_selection.clear();
+	for (int i = 0; i < p_selection.size(); i++) {
+		tile_map_selection.insert(p_selection[i]);
+	}
+	_update_selection_pattern_from_tilemap_selection();
+	_update_tileset_selection_from_selection_pattern();
+	CanvasItemEditor::get_singleton()->update_viewport();
+}
+
+TypedArray<Vector2i> TileMapEditorTilesPlugin::_get_tile_map_selection() const {
+	TypedArray<Vector2i> output;
+	for (Set<Vector2i>::Element *E = tile_map_selection.front(); E; E = E->next()) {
+		output.push_back(E->get());
+	}
+	return output;
+}
+
+void TileMapEditorTilesPlugin::edit(ObjectID p_tile_map_id) {
+	tile_map_id = p_tile_map_id;
+
+	// Clean the selection.
+	tile_set_selection.clear();
+	tile_map_selection.clear();
+	selection_pattern->clear();
+}
+
+void TileMapEditorTilesPlugin::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("_set_tile_map_selection", "selection"), &TileMapEditorTilesPlugin::_set_tile_map_selection);
+	ClassDB::bind_method(D_METHOD("_get_tile_map_selection"), &TileMapEditorTilesPlugin::_get_tile_map_selection);
+}
+
+TileMapEditorTilesPlugin::TileMapEditorTilesPlugin() {
+	CanvasItemEditor::get_singleton()->get_viewport_control()->connect("mouse_exited", callable_mp(this, &TileMapEditorTilesPlugin::_mouse_exited_viewport));
+
+	// --- Shortcuts ---
+	ED_SHORTCUT("tiles_editor/cut", TTR("Cut"), KEY_MASK_CMD | KEY_X);
+	ED_SHORTCUT("tiles_editor/copy", TTR("Copy"), KEY_MASK_CMD | KEY_C);
+	ED_SHORTCUT("tiles_editor/paste", TTR("Paste"), KEY_MASK_CMD | KEY_V);
+	ED_SHORTCUT("tiles_editor/cancel", TTR("Cancel"), KEY_ESCAPE);
+	ED_SHORTCUT("tiles_editor/delete", TTR("Delete"), KEY_DELETE);
+
+	// --- Toolbar ---
+	toolbar = memnew(HBoxContainer);
+
+	HBoxContainer *tilemap_tiles_tools_buttons = memnew(HBoxContainer);
+
+	tool_buttons_group.instance();
+
+	select_tool_button = memnew(Button);
+	select_tool_button->set_flat(true);
+	select_tool_button->set_toggle_mode(true);
+	select_tool_button->set_button_group(tool_buttons_group);
+	select_tool_button->set_shortcut(ED_SHORTCUT("tiles_editor/selection_tool", "Selection", KEY_S));
+	select_tool_button->connect("pressed", callable_mp(this, &TileMapEditorTilesPlugin::_update_toolbar));
+	tilemap_tiles_tools_buttons->add_child(select_tool_button);
+
+	paint_tool_button = memnew(Button);
+	paint_tool_button->set_flat(true);
+	paint_tool_button->set_toggle_mode(true);
+	paint_tool_button->set_button_group(tool_buttons_group);
+	paint_tool_button->set_shortcut(ED_SHORTCUT("tiles_editor/paint_tool", "Paint", KEY_E));
+	paint_tool_button->connect("pressed", callable_mp(this, &TileMapEditorTilesPlugin::_update_toolbar));
+	tilemap_tiles_tools_buttons->add_child(paint_tool_button);
+
+	line_tool_button = memnew(Button);
+	line_tool_button->set_flat(true);
+	line_tool_button->set_toggle_mode(true);
+	line_tool_button->set_button_group(tool_buttons_group);
+	line_tool_button->set_shortcut(ED_SHORTCUT("tiles_editor/line_tool", "Line", KEY_L));
+	line_tool_button->connect("pressed", callable_mp(this, &TileMapEditorTilesPlugin::_update_toolbar));
+	tilemap_tiles_tools_buttons->add_child(line_tool_button);
+
+	rect_tool_button = memnew(Button);
+	rect_tool_button->set_flat(true);
+	rect_tool_button->set_toggle_mode(true);
+	rect_tool_button->set_button_group(tool_buttons_group);
+	rect_tool_button->set_shortcut(ED_SHORTCUT("tiles_editor/rect_tool", "Rect", KEY_R));
+	rect_tool_button->connect("pressed", callable_mp(this, &TileMapEditorTilesPlugin::_update_toolbar));
+	tilemap_tiles_tools_buttons->add_child(rect_tool_button);
+
+	bucket_tool_button = memnew(Button);
+	bucket_tool_button->set_flat(true);
+	bucket_tool_button->set_toggle_mode(true);
+	bucket_tool_button->set_button_group(tool_buttons_group);
+	bucket_tool_button->set_shortcut(ED_SHORTCUT("tiles_editor/bucket_tool", "Bucket", KEY_B));
+	bucket_tool_button->connect("pressed", callable_mp(this, &TileMapEditorTilesPlugin::_update_toolbar));
+	tilemap_tiles_tools_buttons->add_child(bucket_tool_button);
+
+	toolbar->add_child(tilemap_tiles_tools_buttons);
+
+	// -- TileMap tool settings --
+	tools_settings = memnew(HBoxContainer);
+	toolbar->add_child(tools_settings);
+
+	tools_settings_vsep = memnew(VSeparator);
+	tools_settings->add_child(tools_settings_vsep);
+
+	// Picker
+	picker_button = memnew(Button);
+	picker_button->set_flat(true);
+	picker_button->set_toggle_mode(true);
+	picker_button->set_shortcut(ED_SHORTCUT("tiles_editor/picker", "Picker", KEY_P));
+	picker_button->connect("pressed", callable_mp(CanvasItemEditor::get_singleton(), &CanvasItemEditor::update_viewport));
+	tools_settings->add_child(picker_button);
+
+	// Erase button.
+	erase_button = memnew(Button);
+	erase_button->set_flat(true);
+	erase_button->set_toggle_mode(true);
+	erase_button->set_shortcut(ED_SHORTCUT("tiles_editor/eraser", "Eraser", KEY_E));
+	erase_button->connect("pressed", callable_mp(CanvasItemEditor::get_singleton(), &CanvasItemEditor::update_viewport));
+	tools_settings->add_child(erase_button);
+
+	// Separator 2.
+	tools_settings_vsep_2 = memnew(VSeparator);
+	tools_settings->add_child(tools_settings_vsep_2);
+
+	// Continuous checkbox.
+	bucket_continuous_checkbox = memnew(CheckBox);
+	bucket_continuous_checkbox->set_flat(true);
+	bucket_continuous_checkbox->set_text(TTR("Contiguous"));
+	tools_settings->add_child(bucket_continuous_checkbox);
+
+	// Random tile checkbox.
+	random_tile_checkbox = memnew(CheckBox);
+	random_tile_checkbox->set_flat(true);
+	random_tile_checkbox->set_text(TTR("Place random tile"));
+	random_tile_checkbox->connect("toggled", callable_mp(this, &TileMapEditorTilesPlugin::_on_random_tile_checkbox_toggled));
+	tools_settings->add_child(random_tile_checkbox);
+
+	// Random tile scattering.
+	scatter_label = memnew(Label);
+	scatter_label->set_tooltip(TTR("Defines the probability of painting nothing instead of a randomly selected tile."));
+	scatter_label->set_text(TTR("Scattering:"));
+	tools_settings->add_child(scatter_label);
+
+	scatter_spinbox = memnew(SpinBox);
+	scatter_spinbox->set_min(0.0);
+	scatter_spinbox->set_max(1000);
+	scatter_spinbox->set_step(0.001);
+	scatter_spinbox->set_tooltip(TTR("Defines the probability of painting nothing instead of a randomly selected tile."));
+	scatter_spinbox->get_line_edit()->add_theme_constant_override("minimum_character_width", 4);
+	scatter_spinbox->connect("value_changed", callable_mp(this, &TileMapEditorTilesPlugin::_on_scattering_spinbox_changed));
+	tools_settings->add_child(scatter_spinbox);
+
+	_on_random_tile_checkbox_toggled(false);
+
+	// Default tool.
+	paint_tool_button->set_pressed(true);
+	_update_toolbar();
+
+	// --- Bottom panel ---
+	set_name("Tiles");
+
+	missing_source_label = memnew(Label);
+	missing_source_label->set_text(TTR("This TileMap's TileSet has no source configured. Edit the TileSet resource to add one."));
+	missing_source_label->set_h_size_flags(SIZE_EXPAND_FILL);
+	missing_source_label->set_v_size_flags(SIZE_EXPAND_FILL);
+	missing_source_label->set_align(Label::ALIGN_CENTER);
+	missing_source_label->set_valign(Label::VALIGN_CENTER);
+	missing_source_label->hide();
+	add_child(missing_source_label);
+
+	atlas_sources_split_container = memnew(HSplitContainer);
+	atlas_sources_split_container->set_h_size_flags(SIZE_EXPAND_FILL);
+	atlas_sources_split_container->set_v_size_flags(SIZE_EXPAND_FILL);
+	add_child(atlas_sources_split_container);
+
+	sources_list = memnew(ItemList);
+	sources_list->set_fixed_icon_size(Size2i(60, 60) * EDSCALE);
+	sources_list->set_h_size_flags(SIZE_EXPAND_FILL);
+	sources_list->set_stretch_ratio(0.25);
+	sources_list->set_custom_minimum_size(Size2i(70, 0) * EDSCALE);
+	sources_list->connect("item_selected", callable_mp(this, &TileMapEditorTilesPlugin::_update_fix_selected_and_hovered).unbind(1));
+	sources_list->connect("item_selected", callable_mp(this, &TileMapEditorTilesPlugin::_update_atlas_view).unbind(1));
+	sources_list->connect("item_selected", callable_mp(TilesEditor::get_singleton(), &TilesEditor::set_atlas_sources_lists_current));
+	sources_list->connect("visibility_changed", callable_mp(TilesEditor::get_singleton(), &TilesEditor::synchronize_atlas_sources_list), varray(sources_list));
+	//sources_list->set_drag_forwarding(this);
+	atlas_sources_split_container->add_child(sources_list);
+
+	tile_atlas_view = memnew(TileAtlasView);
+	tile_atlas_view->set_h_size_flags(SIZE_EXPAND_FILL);
+	tile_atlas_view->set_v_size_flags(SIZE_EXPAND_FILL);
+	tile_atlas_view->set_texture_grid_visible(false);
+	tile_atlas_view->set_tile_shape_grid_visible(false);
+	tile_atlas_view->connect("transform_changed", callable_mp(TilesEditor::get_singleton(), &TilesEditor::set_atlas_view_transform));
+	//tile_atlas_view->connect("visibility_changed", callable_mp(TilesEditor::get_singleton(), &TilesEditor::synchronize_atlas_view), varray(tile_atlas_view));
+	atlas_sources_split_container->add_child(tile_atlas_view);
+
+	tile_atlas_control = memnew(Control);
+	tile_atlas_control->connect("draw", callable_mp(this, &TileMapEditorTilesPlugin::_tile_atlas_control_draw));
+	tile_atlas_control->connect("mouse_exited", callable_mp(this, &TileMapEditorTilesPlugin::_tile_atlas_control_mouse_exited));
+	tile_atlas_control->connect("gui_input", callable_mp(this, &TileMapEditorTilesPlugin::_tile_atlas_control_gui_input));
+	tile_atlas_view->add_control_over_atlas_tiles(tile_atlas_control);
+
+	alternative_tiles_control = memnew(Control);
+	alternative_tiles_control->connect("draw", callable_mp(this, &TileMapEditorTilesPlugin::_tile_alternatives_control_draw));
+	alternative_tiles_control->connect("mouse_exited", callable_mp(this, &TileMapEditorTilesPlugin::_tile_alternatives_control_mouse_exited));
+	alternative_tiles_control->connect("gui_input", callable_mp(this, &TileMapEditorTilesPlugin::_tile_alternatives_control_gui_input));
+	tile_atlas_view->add_control_over_alternative_tiles(alternative_tiles_control);
+
+	_update_bottom_panel();
+}
+
+TileMapEditorTilesPlugin::~TileMapEditorTilesPlugin() {
+	memdelete(selection_pattern);
+	memdelete(tile_map_clipboard);
+}
+
+void TileMapEditorTerrainsPlugin::_notification(int p_what) {
+	switch (p_what) {
+		case NOTIFICATION_ENTER_TREE:
+		case NOTIFICATION_THEME_CHANGED:
+			paint_tool_button->set_icon(get_theme_icon("Edit", "EditorIcons"));
+			picker_button->set_icon(get_theme_icon("ColorPick", "EditorIcons"));
+			erase_button->set_icon(get_theme_icon("Eraser", "EditorIcons"));
+			break;
+	}
+}
+
+void TileMapEditorTerrainsPlugin::tile_set_changed() {
+	_update_terrains_cache();
+	_update_terrains_tree();
+	_update_tiles_list();
+}
+
+void TileMapEditorTerrainsPlugin::_update_toolbar() {
+	// Hide all settings.
+	for (int i = 0; i < tools_settings->get_child_count(); i++) {
+		Object::cast_to<CanvasItem>(tools_settings->get_child(i))->hide();
+	}
+
+	// Show only the correct settings.
+	if (tool_buttons_group->get_pressed_button() == paint_tool_button) {
+		tools_settings_vsep->show();
+		picker_button->show();
+		erase_button->show();
+	}
+}
+
+Control *TileMapEditorTerrainsPlugin::get_toolbar() const {
+	return toolbar;
+}
+
+Map<Vector2i, TileSet::CellNeighbor> TileMapEditorTerrainsPlugin::Constraint::get_overlapping_coords_and_peering_bits() const {
+	Map<Vector2i, TileSet::CellNeighbor> output;
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	ERR_FAIL_COND_V(!tile_set.is_valid(), output);
+
+	TileSet::TileShape shape = tile_set->get_tile_shape();
+	if (shape == TileSet::TILE_SHAPE_SQUARE) {
+		switch (bit) {
+			case 0:
+				output[base_cell_coords] = TileSet::CELL_NEIGHBOR_RIGHT_SIDE;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_LEFT_SIDE;
+				break;
+			case 1:
+				output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER)] = TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_RIGHT_CORNER;
+				break;
+			case 2:
+				output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_SIDE;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_SIDE;
+				break;
+			case 3:
+				output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER)] = TileSet::CELL_NEIGHBOR_TOP_RIGHT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_LEFT_SIDE)] = TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER;
+				break;
+			default:
+				ERR_FAIL_V(output);
+		}
+	} else if (shape == TileSet::TILE_SHAPE_ISOMETRIC) {
+		switch (bit) {
+			case 0:
+				output[base_cell_coords] = TileSet::CELL_NEIGHBOR_RIGHT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_BOTTOM_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_RIGHT_CORNER)] = TileSet::CELL_NEIGHBOR_LEFT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_CORNER;
+				break;
+			case 1:
+				output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE;
+				break;
+			case 2:
+				output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_LEFT_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_CORNER)] = TileSet::CELL_NEIGHBOR_TOP_CORNER;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE)] = TileSet::CELL_NEIGHBOR_RIGHT_CORNER;
+				break;
+			case 3:
+				output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE;
+				output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE;
+				break;
+			default:
+				ERR_FAIL_V(output);
+		}
+	} else {
+		// Half offset shapes.
+		TileSet::TileOffsetAxis offset_axis = tile_set->get_tile_offset_axis();
+		if (offset_axis == TileSet::TILE_OFFSET_AXIS_HORIZONTAL) {
+			switch (bit) {
+				case 0:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_RIGHT_SIDE;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_LEFT_SIDE;
+					break;
+				case 1:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_CORNER;
+					break;
+				case 2:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE;
+					break;
+				case 3:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_CORNER;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_RIGHT_CORNER;
+					break;
+				case 4:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE;
+					break;
+				default:
+					ERR_FAIL_V(output);
+			}
+		} else {
+			switch (bit) {
+				case 0:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_RIGHT_CORNER;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER;
+					break;
+				case 1:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE;
+					break;
+				case 2:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)] = TileSet::CELL_NEIGHBOR_LEFT_CORNER;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER;
+					break;
+				case 3:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_SIDE;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_SIDE;
+					break;
+				case 4:
+					output[base_cell_coords] = TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE;
+					output[tile_map->get_neighbor_cell(base_cell_coords, TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE)] = TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE;
+					break;
+				default:
+					ERR_FAIL_V(output);
+			}
+		}
+	}
+	return output;
+}
+
+TileMapEditorTerrainsPlugin::Constraint::Constraint(const TileMap *p_tile_map, const Vector2i &p_position, const TileSet::CellNeighbor &p_bit, int p_terrain) {
+	// The way we build the constraint make it easy to detect conflicting constraints.
+	tile_map = p_tile_map;
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	ERR_FAIL_COND(!tile_set.is_valid());
+
+	TileSet::TileShape shape = tile_set->get_tile_shape();
+	if (shape == TileSet::TILE_SHAPE_SQUARE || shape == TileSet::TILE_SHAPE_ISOMETRIC) {
+		switch (p_bit) {
+			case TileSet::CELL_NEIGHBOR_RIGHT_SIDE:
+			case TileSet::CELL_NEIGHBOR_RIGHT_CORNER:
+				bit = 0;
+				base_cell_coords = p_position;
+				break;
+			case TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER:
+			case TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE:
+				bit = 1;
+				base_cell_coords = p_position;
+				break;
+			case TileSet::CELL_NEIGHBOR_BOTTOM_SIDE:
+			case TileSet::CELL_NEIGHBOR_BOTTOM_CORNER:
+				bit = 2;
+				base_cell_coords = p_position;
+				break;
+			case TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER:
+			case TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE:
+				bit = 3;
+				base_cell_coords = p_position;
+				break;
+			case TileSet::CELL_NEIGHBOR_LEFT_SIDE:
+			case TileSet::CELL_NEIGHBOR_LEFT_CORNER:
+				bit = 0;
+				base_cell_coords = p_tile_map->get_neighbor_cell(p_position, p_bit);
+				break;
+			case TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER:
+			case TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE:
+				bit = 1;
+				base_cell_coords = p_tile_map->get_neighbor_cell(p_position, p_bit);
+				break;
+			case TileSet::CELL_NEIGHBOR_TOP_SIDE:
+			case TileSet::CELL_NEIGHBOR_TOP_CORNER:
+				bit = 2;
+				base_cell_coords = p_tile_map->get_neighbor_cell(p_position, p_bit);
+				break;
+			case TileSet::CELL_NEIGHBOR_TOP_RIGHT_CORNER:
+			case TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE:
+				bit = 3;
+				base_cell_coords = p_tile_map->get_neighbor_cell(p_position, p_bit);
+				break;
+			default:
+				ERR_FAIL();
+				break;
+		}
+	} else {
+		// Half-offset shapes
+		TileSet::TileOffsetAxis offset_axis = tile_set->get_tile_offset_axis();
+		if (offset_axis == TileSet::TILE_OFFSET_AXIS_HORIZONTAL) {
+			switch (p_bit) {
+				case TileSet::CELL_NEIGHBOR_RIGHT_SIDE:
+					bit = 0;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER:
+					bit = 1;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE:
+					bit = 2;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_CORNER:
+					bit = 3;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE:
+					bit = 4;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER:
+					bit = 1;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_LEFT_SIDE:
+					bit = 0;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER:
+					bit = 3;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE:
+					bit = 2;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_CORNER:
+					bit = 1;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE:
+					bit = 4;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_RIGHT_CORNER:
+					bit = 3;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE);
+					break;
+				default:
+					ERR_FAIL();
+					break;
+			}
+		} else {
+			switch (p_bit) {
+				case TileSet::CELL_NEIGHBOR_RIGHT_CORNER:
+					bit = 0;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE:
+					bit = 1;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER:
+					bit = 2;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_SIDE:
+					bit = 3;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER:
+					bit = 0;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE:
+					bit = 4;
+					base_cell_coords = p_position;
+					break;
+				case TileSet::CELL_NEIGHBOR_LEFT_CORNER:
+					bit = 2;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE:
+					bit = 1;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER:
+					bit = 0;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_SIDE:
+					bit = 3;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_RIGHT_CORNER:
+					bit = 2;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_SIDE);
+					break;
+				case TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE:
+					bit = 4;
+					base_cell_coords = p_tile_map->get_neighbor_cell(p_position, TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE);
+					break;
+				default:
+					ERR_FAIL();
+					break;
+			}
+		}
+	}
+	terrain = p_terrain;
+}
+
+Set<TileMapEditorTerrainsPlugin::TerrainsTilePattern> TileMapEditorTerrainsPlugin::_get_valid_terrains_tile_patterns_for_constraints(int p_terrain_set, const Vector2i &p_position, Set<Constraint> p_constraints) const {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return Set<TerrainsTilePattern>();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return Set<TerrainsTilePattern>();
+	}
+
+	// Returns all tiles compatible with the given constraints.
+	Set<TerrainsTilePattern> compatible_terrain_tile_patterns;
+	for (Map<TerrainsTilePattern, Set<TileMapCell>>::Element *E = per_terrain_terrains_tile_patterns_tiles[p_terrain_set].front(); E; E = E->next()) {
+		int valid = true;
+		int in_pattern_count = 0;
+		for (int i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) {
+			TileSet::CellNeighbor bit = TileSet::CellNeighbor(i);
+			if (tile_set->is_valid_peering_bit_terrain(p_terrain_set, bit)) {
+				// Check if the bit is compatible with the constraints.
+				Constraint terrain_bit_constraint = Constraint(tile_map, p_position, bit, E->key()[in_pattern_count]);
+
+				Set<Constraint>::Element *in_set_constraint_element = p_constraints.find(terrain_bit_constraint);
+				if (in_set_constraint_element && in_set_constraint_element->get().get_terrain() != terrain_bit_constraint.get_terrain()) {
+					valid = false;
+					break;
+				}
+				in_pattern_count++;
+			}
+		}
+
+		if (valid) {
+			compatible_terrain_tile_patterns.insert(E->key());
+		}
+	}
+
+	return compatible_terrain_tile_patterns;
+}
+
+Set<TileMapEditorTerrainsPlugin::Constraint> TileMapEditorTerrainsPlugin::_get_constraints_from_removed_cells_list(const Set<Vector2i> &p_to_replace, int p_terrain_set) const {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return Set<Constraint>();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return Set<Constraint>();
+	}
+
+	ERR_FAIL_INDEX_V(p_terrain_set, tile_set->get_terrain_sets_count(), Set<Constraint>());
+
+	// Build a set of dummy constraints get the constrained points.
+	Set<Constraint> dummy_constraints;
+	for (Set<Vector2i>::Element *E = p_to_replace.front(); E; E = E->next()) {
+		for (int i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) { // Iterates over sides.
+			TileSet::CellNeighbor bit = TileSet::CellNeighbor(i);
+			if (tile_set->is_valid_peering_bit_terrain(p_terrain_set, bit)) {
+				dummy_constraints.insert(Constraint(tile_map, E->get(), bit, -1));
+			}
+		}
+	}
+
+	// For each constrained point, we get all overlapping tiles, and select the most adequate terrain for it.
+	Set<Constraint> constraints;
+	for (Set<Constraint>::Element *E = dummy_constraints.front(); E; E = E->next()) {
+		Constraint c = E->get();
+
+		Map<int, int> terrain_count;
+
+		// Count the number of occurences per terrain.
+		Map<Vector2i, TileSet::CellNeighbor> overlapping_terrain_bits = c.get_overlapping_coords_and_peering_bits();
+		for (Map<Vector2i, TileSet::CellNeighbor>::Element *E_overlapping = overlapping_terrain_bits.front(); E_overlapping; E_overlapping = E_overlapping->next()) {
+			if (!p_to_replace.has(E_overlapping->key())) {
+				TileMapCell neighbor_cell = tile_map->get_cell(E_overlapping->key());
+				TileData *neighbor_tile_data = nullptr;
+				if (terrain_tiles.has(neighbor_cell) && terrain_tiles[neighbor_cell]->get_terrain_set() == p_terrain_set) {
+					neighbor_tile_data = terrain_tiles[neighbor_cell];
+				}
+
+				int terrain = neighbor_tile_data ? neighbor_tile_data->get_peering_bit_terrain(TileSet::CellNeighbor(E_overlapping->get())) : -1;
+				if (terrain_count.has(terrain)) {
+					terrain_count[terrain] = 0;
+				}
+				terrain_count[terrain] += 1;
+			}
+		}
+
+		// Get the terrain with the max number of occurences.
+		int max = 0;
+		int max_terrain = -1;
+		for (Map<int, int>::Element *E_terrain_count = terrain_count.front(); E_terrain_count; E_terrain_count = E_terrain_count->next()) {
+			if (E_terrain_count->get() > max) {
+				max = E_terrain_count->get();
+				max_terrain = E_terrain_count->key();
+			}
+		}
+
+		// Set the adequate terrain.
+		if (max > 0) {
+			c.set_terrain(max_terrain);
+			constraints.insert(c);
+		}
+	}
+
+	return constraints;
+}
+
+Set<TileMapEditorTerrainsPlugin::Constraint> TileMapEditorTerrainsPlugin::_get_constraints_from_added_tile(Vector2i p_position, int p_terrain_set, TerrainsTilePattern p_terrains_tile_pattern) const {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return Set<TileMapEditorTerrainsPlugin::Constraint>();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return Set<TileMapEditorTerrainsPlugin::Constraint>();
+	}
+
+	// Compute the constraints needed from the surrounding tiles.
+	Set<TileMapEditorTerrainsPlugin::Constraint> output;
+	int in_pattern_count = 0;
+	for (uint32_t i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) {
+		TileSet::CellNeighbor side = TileSet::CellNeighbor(i);
+		if (tile_set->is_valid_peering_bit_terrain(p_terrain_set, side)) {
+			Constraint c = Constraint(tile_map, p_position, side, p_terrains_tile_pattern[in_pattern_count]);
+			output.insert(c);
+			in_pattern_count++;
+		}
+	}
+
+	return output;
+}
+
+Map<Vector2i, TileMapEditorTerrainsPlugin::TerrainsTilePattern> TileMapEditorTerrainsPlugin::_wave_function_collapse(const Set<Vector2i> &p_to_replace, int p_terrain_set, const Set<TileMapEditorTerrainsPlugin::Constraint> p_constraints) const {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return Map<Vector2i, TerrainsTilePattern>();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return Map<Vector2i, TileMapEditorTerrainsPlugin::TerrainsTilePattern>();
+	}
+
+	// Copy the constraints set.
+	Set<TileMapEditorTerrainsPlugin::Constraint> constraints = p_constraints;
+
+	// Compute all acceptable tiles for each cell.
+	Map<Vector2i, Set<TerrainsTilePattern>> per_cell_acceptable_tiles;
+	for (Set<Vector2i>::Element *E = p_to_replace.front(); E; E = E->next()) {
+		per_cell_acceptable_tiles[E->get()] = _get_valid_terrains_tile_patterns_for_constraints(p_terrain_set, E->get(), constraints);
+	}
+
+	// Ouput map.
+	Map<Vector2i, TerrainsTilePattern> output;
+
+	// Add all positions to a set.
+	Set<Vector2i> to_replace = Set<Vector2i>(p_to_replace);
+	while (!to_replace.is_empty()) {
+		// Compute the minimum number of tile possibilities for each cell.
+		int min_nb_possibilities = 100000000;
+		for (Map<Vector2i, Set<TerrainsTilePattern>>::Element *E = per_cell_acceptable_tiles.front(); E; E = E->next()) {
+			min_nb_possibilities = MIN(min_nb_possibilities, E->get().size());
+		}
+
+		// Get the set of possible cells to fill.
+		LocalVector<Vector2i> to_choose_from;
+		for (Map<Vector2i, Set<TerrainsTilePattern>>::Element *E = per_cell_acceptable_tiles.front(); E; E = E->next()) {
+			if (E->get().size() == min_nb_possibilities) {
+				to_choose_from.push_back(E->key());
+			}
+		}
+
+		// Randomly pick a tile out of the most constrained.
+		Vector2i selected_cell_to_replace = to_choose_from[Math::random(0, to_choose_from.size() - 1)];
+
+		// Randomly select a tile out of them the put it in the grid.
+		Set<TerrainsTilePattern> valid_tiles = per_cell_acceptable_tiles[selected_cell_to_replace];
+		if (valid_tiles.is_empty()) {
+			// No possibilities :/
+			break;
+		}
+		int random_terrain_tile_pattern_index = Math::random(0, valid_tiles.size() - 1);
+		Set<TerrainsTilePattern>::Element *E = valid_tiles.front();
+		for (int i = 0; i < random_terrain_tile_pattern_index; i++) {
+			E = E->next();
+		}
+		TerrainsTilePattern selected_terrain_tile_pattern = E->get();
+
+		// Set the selected cell into the output.
+		output[selected_cell_to_replace] = selected_terrain_tile_pattern;
+		to_replace.erase(selected_cell_to_replace);
+		per_cell_acceptable_tiles.erase(selected_cell_to_replace);
+
+		// Add the new constraints from the added tiles.
+		Set<TileMapEditorTerrainsPlugin::Constraint> new_constraints = _get_constraints_from_added_tile(selected_cell_to_replace, p_terrain_set, selected_terrain_tile_pattern);
+		for (Set<TileMapEditorTerrainsPlugin::Constraint>::Element *E_constraint = new_constraints.front(); E_constraint; E_constraint = E_constraint->next()) {
+			constraints.insert(E_constraint->get());
+		}
+
+		// Compute valid tiles again for neighbors.
+		for (uint32_t i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) {
+			TileSet::CellNeighbor side = TileSet::CellNeighbor(i);
+			if (tile_map->is_existing_neighbor(side)) {
+				Vector2i neighbor = tile_map->get_neighbor_cell(selected_cell_to_replace, side);
+				if (to_replace.has(neighbor)) {
+					per_cell_acceptable_tiles[neighbor] = _get_valid_terrains_tile_patterns_for_constraints(p_terrain_set, neighbor, constraints);
+				}
+			}
+		}
+	}
+	return output;
+}
+
+TileMapCell TileMapEditorTerrainsPlugin::_get_random_tile_from_pattern(int p_terrain_set, TerrainsTilePattern p_terrain_tile_pattern) const {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return TileMapCell();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return TileMapCell();
+	}
+
+	// Count the sum of probabilities.
+	double sum = 0.0;
+	Set<TileMapCell> set = per_terrain_terrains_tile_patterns_tiles[p_terrain_set][p_terrain_tile_pattern];
+	for (Set<TileMapCell>::Element *E = set.front(); E; E = E->next()) {
+		if (E->get().source_id >= 0) {
+			Ref<TileSetSource> source = tile_set->get_source(E->get().source_id);
+
+			Ref<TileSetAtlasSource> atlas_source = source;
+			if (atlas_source.is_valid()) {
+				TileData *tile_data = Object::cast_to<TileData>(atlas_source->get_tile_data(E->get().get_atlas_coords(), E->get().alternative_tile));
+				sum += tile_data->get_probability();
+			} else {
+				sum += 1.0;
+			}
+		} else {
+			sum += 1.0;
+		}
+	}
+
+	// Generate a random number.
+	double count = 0.0;
+	double picked = Math::random(0.0, sum);
+
+	// Pick the tile.
+	for (Set<TileMapCell>::Element *E = set.front(); E; E = E->next()) {
+		if (E->get().source_id >= 0) {
+			Ref<TileSetSource> source = tile_set->get_source(E->get().source_id);
+
+			Ref<TileSetAtlasSource> atlas_source = source;
+			if (atlas_source.is_valid()) {
+				TileData *tile_data = Object::cast_to<TileData>(atlas_source->get_tile_data(E->get().get_atlas_coords(), E->get().alternative_tile));
+				count += tile_data->get_probability();
+			} else {
+				count += 1.0;
+			}
+		} else {
+			count += 1.0;
+		}
+
+		if (count >= picked) {
+			return E->get();
+		}
+	}
+
+	ERR_FAIL_V(TileMapCell());
+}
+
+Map<Vector2i, TileMapCell> TileMapEditorTerrainsPlugin::_draw_terrains(const Map<Vector2i, TerrainsTilePattern> &p_to_paint, int p_terrain_set) const {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return Map<Vector2i, TileMapCell>();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return Map<Vector2i, TileMapCell>();
+	}
+
+	Map<Vector2i, TileMapCell> output;
+
+	// Add the constraints from the added tiles.
+	Set<TileMapEditorTerrainsPlugin::Constraint> added_tiles_constraints_set;
+	for (Map<Vector2i, TerrainsTilePattern>::Element *E_to_paint = p_to_paint.front(); E_to_paint; E_to_paint = E_to_paint->next()) {
+		Vector2i coords = E_to_paint->key();
+		TerrainsTilePattern terrains_tile_pattern = E_to_paint->get();
+
+		Set<TileMapEditorTerrainsPlugin::Constraint> cell_constraints = _get_constraints_from_added_tile(coords, p_terrain_set, terrains_tile_pattern);
+		for (Set<TileMapEditorTerrainsPlugin::Constraint>::Element *E = cell_constraints.front(); E; E = E->next()) {
+			added_tiles_constraints_set.insert(E->get());
+		}
+	}
+
+	// Build the list of potential tiles to replace.
+	Set<Vector2i> potential_to_replace;
+	for (Map<Vector2i, TerrainsTilePattern>::Element *E_to_paint = p_to_paint.front(); E_to_paint; E_to_paint = E_to_paint->next()) {
+		Vector2i coords = E_to_paint->key();
+		for (int i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) {
+			if (tile_map->is_existing_neighbor(TileSet::CellNeighbor(i))) {
+				Vector2i neighbor = tile_map->get_neighbor_cell(coords, TileSet::CellNeighbor(i));
+				if (!p_to_paint.has(neighbor)) {
+					potential_to_replace.insert(neighbor);
+				}
+			}
+		}
+	}
+
+	// Set of tiles to replace
+	Set<Vector2i> to_replace;
+
+	// Add the central tiles to the one to replace. TODO: maybe change that.
+	for (Map<Vector2i, TerrainsTilePattern>::Element *E_to_paint = p_to_paint.front(); E_to_paint; E_to_paint = E_to_paint->next()) {
+		to_replace.insert(E_to_paint->key());
+	}
+
+	// Add the constraints from the surroundings of the modified areas.
+	Set<TileMapEditorTerrainsPlugin::Constraint> removed_cells_constraints_set;
+	bool to_replace_modified = true;
+	while (to_replace_modified) {
+		// Get the constraints from the removed cells.
+		removed_cells_constraints_set = _get_constraints_from_removed_cells_list(to_replace, p_terrain_set);
+
+		// Filter the sources to make sure they are in the potential_to_replace.
+		Map<Constraint, Set<Vector2i>> source_tiles_of_constraint;
+		for (Set<Constraint>::Element *E = removed_cells_constraints_set.front(); E; E = E->next()) {
+			Map<Vector2i, TileSet::CellNeighbor> sources_of_constraint = E->get().get_overlapping_coords_and_peering_bits();
+			for (Map<Vector2i, TileSet::CellNeighbor>::Element *E_source_tile_of_constraint = sources_of_constraint.front(); E_source_tile_of_constraint; E_source_tile_of_constraint = E_source_tile_of_constraint->next()) {
+				if (potential_to_replace.has(E_source_tile_of_constraint->key())) {
+					source_tiles_of_constraint[E->get()].insert(E_source_tile_of_constraint->key());
+				}
+			}
+		}
+
+		to_replace_modified = false;
+		for (Set<TileMapEditorTerrainsPlugin::Constraint>::Element *E = added_tiles_constraints_set.front(); E; E = E->next()) {
+			Constraint c = E->get();
+			// Check if we have a conflict in constraints.
+			if (removed_cells_constraints_set.has(c) && removed_cells_constraints_set.find(c)->get().get_terrain() != c.get_terrain()) {
+				// If we do, we search for a neighbor to remove.
+				if (source_tiles_of_constraint.has(c) && !source_tiles_of_constraint[c].is_empty()) {
+					// Remove it.
+					Vector2i to_add_to_remove = source_tiles_of_constraint[c].front()->get();
+					potential_to_replace.erase(to_add_to_remove);
+					to_replace.insert(to_add_to_remove);
+					to_replace_modified = true;
+					for (Map<Constraint, Set<Vector2i>>::Element *E_source_tiles_of_constraint = source_tiles_of_constraint.front(); E_source_tiles_of_constraint; E_source_tiles_of_constraint = E_source_tiles_of_constraint->next()) {
+						E_source_tiles_of_constraint->get().erase(to_add_to_remove);
+					}
+					break;
+				}
+			}
+		}
+	}
+
+	// Combine all constraints together.
+	Set<TileMapEditorTerrainsPlugin::Constraint> constraints = removed_cells_constraints_set;
+	for (Set<TileMapEditorTerrainsPlugin::Constraint>::Element *E = added_tiles_constraints_set.front(); E; E = E->next()) {
+		constraints.insert(E->get());
+	}
+
+	// Run WFC to fill the holes with the constraints.
+	Map<Vector2i, TerrainsTilePattern> wfc_output = _wave_function_collapse(to_replace, p_terrain_set, constraints);
+
+	// Use the WFC run for the output.
+	for (Map<Vector2i, TerrainsTilePattern>::Element *E = wfc_output.front(); E; E = E->next()) {
+		output[E->key()] = _get_random_tile_from_pattern(p_terrain_set, E->get());
+	}
+
+	// Override the WFC results to make sure at least the painted tiles are acutally painted.
+	for (Map<Vector2i, TerrainsTilePattern>::Element *E_to_paint = p_to_paint.front(); E_to_paint; E_to_paint = E_to_paint->next()) {
+		output[E_to_paint->key()] = _get_random_tile_from_pattern(p_terrain_set, E_to_paint->get());
+	}
+
+	return output;
+}
+
+bool TileMapEditorTerrainsPlugin::forward_canvas_gui_input(const Ref<InputEvent> &p_event) {
+	if (!is_visible_in_tree()) {
+		// If the bottom editor is not visible, we ignore inputs.
+		return false;
+	}
+
+	if (CanvasItemEditor::get_singleton()->get_current_tool() != CanvasItemEditor::TOOL_SELECT) {
+		return false;
+	}
+
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return false;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return false;
+	}
+
+	// Get the selected terrain.
+	TerrainsTilePattern selected_terrains_tile_pattern;
+	int selected_terrain_set = -1;
+
+	TreeItem *selected_tree_item = terrains_tree->get_selected();
+	if (selected_tree_item && selected_tree_item->get_metadata(0)) {
+		Dictionary metadata_dict = selected_tree_item->get_metadata(0);
+		// Selected terrain
+		selected_terrain_set = metadata_dict["terrain_set"];
+
+		// Selected tile
+		if (erase_button->is_pressed()) {
+			selected_terrains_tile_pattern.clear();
+			for (uint32_t i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) {
+				TileSet::CellNeighbor side = TileSet::CellNeighbor(i);
+				if (tile_set->is_valid_peering_bit_terrain(selected_terrain_set, side)) {
+					selected_terrains_tile_pattern.push_back(-1);
+				}
+			}
+		} else if (terrains_tile_list->is_anything_selected()) {
+			metadata_dict = terrains_tile_list->get_item_metadata(terrains_tile_list->get_selected_items()[0]);
+			selected_terrains_tile_pattern = metadata_dict["terrains_tile_pattern"];
+		}
+	}
+
+	Ref<InputEventMouseMotion> mm = p_event;
+	if (mm.is_valid()) {
+		Transform2D xform = CanvasItemEditor::get_singleton()->get_canvas_transform() * tile_map->get_global_transform();
+		Vector2 mpos = xform.affine_inverse().xform(mm->get_position());
+
+		switch (drag_type) {
+			case DRAG_TYPE_PAINT: {
+				if (selected_terrain_set >= 0) {
+					Vector<Vector2i> line = TileMapEditor::get_line(tile_map, tile_map->world_to_map(drag_last_mouse_pos), tile_map->world_to_map(mpos));
+					Map<Vector2i, TerrainsTilePattern> to_draw;
+					for (int i = 0; i < line.size(); i++) {
+						to_draw[line[i]] = selected_terrains_tile_pattern;
+					}
+					Map<Vector2i, TileMapCell> modified = _draw_terrains(to_draw, selected_terrain_set);
+					for (Map<Vector2i, TileMapCell>::Element *E = modified.front(); E; E = E->next()) {
+						if (!drag_modified.has(E->key())) {
+							drag_modified[E->key()] = tile_map->get_cell(E->key());
+						}
+						tile_map->set_cell(E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+					}
+				}
+			} break;
+			default:
+				break;
+		}
+		drag_last_mouse_pos = mpos;
+		CanvasItemEditor::get_singleton()->update_viewport();
+
+		return true;
+	}
+
+	Ref<InputEventMouseButton> mb = p_event;
+	if (mb.is_valid()) {
+		Transform2D xform = CanvasItemEditor::get_singleton()->get_canvas_transform() * tile_map->get_global_transform();
+		Vector2 mpos = xform.affine_inverse().xform(mb->get_position());
+
+		if (mb->get_button_index() == MOUSE_BUTTON_LEFT) {
+			if (mb->is_pressed()) {
+				// Pressed
+				if (picker_button->is_pressed()) {
+					drag_type = DRAG_TYPE_PICK;
+				} else {
+					// Paint otherwise.
+					if (selected_terrain_set >= 0 && !selected_terrains_tile_pattern.is_empty() && tool_buttons_group->get_pressed_button() == paint_tool_button) {
+						drag_type = DRAG_TYPE_PAINT;
+						drag_start_mouse_pos = mpos;
+
+						drag_modified.clear();
+
+						Map<Vector2i, TerrainsTilePattern> terrains_to_draw;
+						terrains_to_draw[tile_map->world_to_map(mpos)] = selected_terrains_tile_pattern;
+
+						Map<Vector2i, TileMapCell> to_draw = _draw_terrains(terrains_to_draw, selected_terrain_set);
+						for (Map<Vector2i, TileMapCell>::Element *E = to_draw.front(); E; E = E->next()) {
+							drag_modified[E->key()] = tile_map->get_cell(E->key());
+							tile_map->set_cell(E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+						}
+					}
+				}
+			} else {
+				// Released
+				switch (drag_type) {
+					case DRAG_TYPE_PICK: {
+						Vector2i coords = tile_map->world_to_map(mpos);
+						TileMapCell tile = tile_map->get_cell(coords);
+
+						if (terrain_tiles.has(tile)) {
+							Array terrains_tile_pattern = _build_terrains_tile_pattern(terrain_tiles[tile]);
+
+							// Find the tree item for the right terrain set.
+							bool need_tree_item_switch = true;
+							TreeItem *tree_item = terrains_tree->get_selected();
+							if (tree_item) {
+								Dictionary metadata_dict = tree_item->get_metadata(0);
+								if (metadata_dict.has("terrain_set") && metadata_dict.has("terrain_id")) {
+									int terrain_set = metadata_dict["terrain_set"];
+									int terrain_id = metadata_dict["terrain_id"];
+									if (per_terrain_terrains_tile_patterns[terrain_set][terrain_id].has(terrains_tile_pattern)) {
+										need_tree_item_switch = false;
+									}
+								}
+							}
+
+							if (need_tree_item_switch) {
+								for (tree_item = terrains_tree->get_root()->get_children(); tree_item; tree_item = tree_item->get_next_visible()) {
+									Dictionary metadata_dict = tree_item->get_metadata(0);
+									if (metadata_dict.has("terrain_set") && metadata_dict.has("terrain_id")) {
+										int terrain_set = metadata_dict["terrain_set"];
+										int terrain_id = metadata_dict["terrain_id"];
+										if (per_terrain_terrains_tile_patterns[terrain_set][terrain_id].has(terrains_tile_pattern)) {
+											// Found
+											tree_item->select(0);
+											_update_tiles_list();
+											break;
+										}
+									}
+								}
+							}
+
+							// Find the list item for the given tile.
+							if (tree_item) {
+								for (int i = 0; i < terrains_tile_list->get_item_count(); i++) {
+									Dictionary metadata_dict = terrains_tile_list->get_item_metadata(i);
+									TerrainsTilePattern in_meta_terrains_tile_pattern = metadata_dict["terrains_tile_pattern"];
+									bool equals = true;
+									for (int j = 0; j < terrains_tile_pattern.size(); j++) {
+										if (terrains_tile_pattern[j] != in_meta_terrains_tile_pattern[j]) {
+											equals = false;
+											break;
+										}
+									}
+									if (equals) {
+										terrains_tile_list->select(i);
+										break;
+									}
+								}
+							} else {
+								ERR_PRINT("Terrain tile not found.");
+							}
+						}
+						picker_button->set_pressed(false);
+					} break;
+					case DRAG_TYPE_PAINT: {
+						undo_redo->create_action(TTR("Paint terrain"));
+						for (Map<Vector2i, TileMapCell>::Element *E = drag_modified.front(); E; E = E->next()) {
+							undo_redo->add_do_method(tile_map, "set_cell", E->key(), tile_map->get_cell_source_id(E->key()), tile_map->get_cell_atlas_coords(E->key()), tile_map->get_cell_alternative_tile(E->key()));
+							undo_redo->add_undo_method(tile_map, "set_cell", E->key(), E->get().source_id, E->get().get_atlas_coords(), E->get().alternative_tile);
+						}
+						undo_redo->commit_action(false);
+					} break;
+					default:
+						break;
+				}
+				drag_type = DRAG_TYPE_NONE;
+			}
+
+			CanvasItemEditor::get_singleton()->update_viewport();
+
+			return true;
+		}
+		drag_last_mouse_pos = mpos;
+	}
+
+	return false;
+}
+
+TileMapEditorTerrainsPlugin::TerrainsTilePattern TileMapEditorTerrainsPlugin::_build_terrains_tile_pattern(TileData *p_tile_data) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return TerrainsTilePattern();
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return TerrainsTilePattern();
+	}
+
+	TerrainsTilePattern output;
+	for (int i = 0; i < TileSet::CELL_NEIGHBOR_MAX; i++) {
+		if (tile_set->is_valid_peering_bit_terrain(p_tile_data->get_terrain_set(), TileSet::CellNeighbor(i))) {
+			output.push_back(p_tile_data->get_peering_bit_terrain(TileSet::CellNeighbor(i)));
+		}
+	}
+	return output;
+}
+
+void TileMapEditorTerrainsPlugin::_update_terrains_cache() {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	// Compute the tile sides.
+	tile_sides.clear();
+	TileSet::TileShape shape = tile_set->get_tile_shape();
+	if (shape == TileSet::TILE_SHAPE_SQUARE) {
+		tile_sides.push_back(TileSet::CELL_NEIGHBOR_RIGHT_SIDE);
+		tile_sides.push_back(TileSet::CELL_NEIGHBOR_BOTTOM_SIDE);
+		tile_sides.push_back(TileSet::CELL_NEIGHBOR_LEFT_SIDE);
+		tile_sides.push_back(TileSet::CELL_NEIGHBOR_TOP_SIDE);
+	} else if (shape == TileSet::TILE_SHAPE_ISOMETRIC) {
+		tile_sides.push_back(TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE);
+		tile_sides.push_back(TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE);
+		tile_sides.push_back(TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+		tile_sides.push_back(TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE);
+	} else {
+		if (tile_set->get_tile_offset_axis() == TileSet::TILE_OFFSET_AXIS_HORIZONTAL) {
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_RIGHT_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_LEFT_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE);
+		} else {
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_BOTTOM_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_TOP_SIDE);
+			tile_sides.push_back(TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE);
+		}
+	}
+
+	// Organizes tiles into structures.
+	per_terrain_terrains_tile_patterns_tiles.resize(tile_set->get_terrain_sets_count());
+	per_terrain_terrains_tile_patterns.resize(tile_set->get_terrain_sets_count());
+	for (int i = 0; i < tile_set->get_terrain_sets_count(); i++) {
+		per_terrain_terrains_tile_patterns_tiles[i].clear();
+		per_terrain_terrains_tile_patterns[i].resize(tile_set->get_terrains_count(i));
+		for (int j = 0; j < (int)per_terrain_terrains_tile_patterns[i].size(); j++) {
+			per_terrain_terrains_tile_patterns[i][j].clear();
+		}
+	}
+
+	for (int source_index = 0; source_index < tile_set->get_source_count(); source_index++) {
+		int source_id = tile_set->get_source_id(source_index);
+		Ref<TileSetSource> source = tile_set->get_source(source_id);
+
+		Ref<TileSetAtlasSource> atlas_source = source;
+		if (atlas_source.is_valid()) {
+			for (int tile_index = 0; tile_index < source->get_tiles_count(); tile_index++) {
+				Vector2i tile_id = source->get_tile_id(tile_index);
+				for (int alternative_index = 0; alternative_index < source->get_alternative_tiles_count(tile_id); alternative_index++) {
+					int alternative_id = source->get_alternative_tile_id(tile_id, alternative_index);
+
+					TileData *tile_data = Object::cast_to<TileData>(atlas_source->get_tile_data(tile_id, alternative_id));
+					int terrain_set = tile_data->get_terrain_set();
+					if (terrain_set >= 0) {
+						ERR_FAIL_INDEX(terrain_set, (int)per_terrain_terrains_tile_patterns.size());
+
+						TileMapCell cell;
+						cell.source_id = source_id;
+						cell.set_atlas_coords(tile_id);
+						cell.alternative_tile = alternative_id;
+
+						TerrainsTilePattern terrains_tile_pattern = _build_terrains_tile_pattern(tile_data);
+
+						// Terrain bits.
+						for (int i = 0; i < terrains_tile_pattern.size(); i++) {
+							int terrain = terrains_tile_pattern[i];
+							if (terrain >= 0 && terrain < (int)per_terrain_terrains_tile_patterns[terrain_set].size()) {
+								per_terrain_terrains_tile_patterns[terrain_set][terrain].insert(terrains_tile_pattern);
+								terrain_tiles[cell] = tile_data;
+								per_terrain_terrains_tile_patterns_tiles[terrain_set][terrains_tile_pattern].insert(cell);
+							}
+						}
+					}
+				}
+			}
+		}
+	}
+
+	// Add the empty cell in the possible patterns and cells.
+	for (int i = 0; i < tile_set->get_terrain_sets_count(); i++) {
+		TerrainsTilePattern empty_pattern;
+		for (int j = 0; j < TileSet::CELL_NEIGHBOR_MAX; j++) {
+			if (tile_set->is_valid_peering_bit_terrain(i, TileSet::CellNeighbor(j))) {
+				empty_pattern.push_back(-1);
+			}
+		}
+
+		TileMapCell empty_cell;
+		empty_cell.source_id = -1;
+		empty_cell.set_atlas_coords(TileSetAtlasSource::INVALID_ATLAS_COORDS);
+		empty_cell.alternative_tile = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+		per_terrain_terrains_tile_patterns_tiles[i][empty_pattern].insert(empty_cell);
+	}
+}
+
+void TileMapEditorTerrainsPlugin::_update_terrains_tree() {
+	terrains_tree->clear();
+	terrains_tree->create_item();
+
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	// Fill in the terrain list.
+	for (int terrain_set_index = 0; terrain_set_index < tile_set->get_terrain_sets_count(); terrain_set_index++) {
+		// Add an item for the terrain set.
+		TreeItem *terrain_set_tree_item = terrains_tree->create_item();
+		String matches;
+		if (tile_set->get_terrain_set_mode(terrain_set_index) == TileSet::TERRAIN_MODE_MATCH_CORNERS_AND_SIDES) {
+			terrain_set_tree_item->set_icon(0, get_theme_icon("TerrainMatchCornersAndSides", "EditorIcons"));
+			matches = String(TTR("Matches corners and sides"));
+		} else if (tile_set->get_terrain_set_mode(terrain_set_index) == TileSet::TERRAIN_MODE_MATCH_CORNERS) {
+			terrain_set_tree_item->set_icon(0, get_theme_icon("TerrainMatchCorners", "EditorIcons"));
+			matches = String(TTR("Matches corners only"));
+		} else {
+			terrain_set_tree_item->set_icon(0, get_theme_icon("TerrainMatchSides", "EditorIcons"));
+			matches = String(TTR("Matches sides only"));
+		}
+		terrain_set_tree_item->set_text(0, vformat("Terrain set %d (%s)", terrain_set_index, matches));
+		terrain_set_tree_item->set_selectable(0, false);
+
+		for (int terrain_index = 0; terrain_index < tile_set->get_terrains_count(terrain_set_index); terrain_index++) {
+			// Compute the terrains_tile_pattern used for terrain preview (whenever possible).
+			TerrainsTilePattern terrains_tile_pattern;
+			int max_bit_count = -1;
+			for (Set<TerrainsTilePattern>::Element *E = per_terrain_terrains_tile_patterns[terrain_set_index][terrain_index].front(); E; E = E->next()) {
+				int count = 0;
+				for (int i = 0; i < E->get().size(); i++) {
+					if (int(E->get()[i]) == terrain_index) {
+						count++;
+					}
+				}
+				if (count > max_bit_count) {
+					terrains_tile_pattern = E->get();
+					max_bit_count = count;
+				}
+			}
+
+			// Get the preview.
+			Ref<Texture2D> icon;
+			Rect2 region;
+			if (max_bit_count >= 0) {
+				double max_probability = -1.0;
+				for (Set<TileMapCell>::Element *E = per_terrain_terrains_tile_patterns_tiles[terrain_set_index][terrains_tile_pattern].front(); E; E = E->next()) {
+					Ref<TileSetSource> source = tile_set->get_source(E->get().source_id);
+
+					Ref<TileSetAtlasSource> atlas_source = source;
+					if (atlas_source.is_valid()) {
+						TileData *tile_data = Object::cast_to<TileData>(atlas_source->get_tile_data(E->get().get_atlas_coords(), E->get().alternative_tile));
+						if (tile_data->get_probability() > max_probability) {
+							icon = atlas_source->get_texture();
+							region = atlas_source->get_tile_texture_region(E->get().get_atlas_coords());
+							max_probability = tile_data->get_probability();
+						}
+					}
+				}
+			} else {
+				Ref<Image> image;
+				image.instance();
+				image->create(1, 1, false, Image::FORMAT_RGBA8);
+				image->set_pixel(0, 0, tile_set->get_terrain_color(terrain_set_index, terrain_index));
+				Ref<ImageTexture> image_texture;
+				image_texture.instance();
+				image_texture->create_from_image(image);
+				image_texture->set_size_override(Size2(32, 32) * EDSCALE);
+				icon = image_texture;
+			}
+
+			// Add the item to the terrain list.
+			TreeItem *terrain_tree_item = terrains_tree->create_item(terrain_set_tree_item);
+			terrain_tree_item->set_text(0, tile_set->get_terrain_name(terrain_set_index, terrain_index));
+			terrain_tree_item->set_icon_max_width(0, 32 * EDSCALE);
+			terrain_tree_item->set_icon(0, icon);
+			terrain_tree_item->set_icon_region(0, region);
+			Dictionary metadata_dict;
+			metadata_dict["terrain_set"] = terrain_set_index;
+			metadata_dict["terrain_id"] = terrain_index;
+			terrain_tree_item->set_metadata(0, metadata_dict);
+		}
+	}
+}
+
+void TileMapEditorTerrainsPlugin::_update_tiles_list() {
+	terrains_tile_list->clear();
+
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	TreeItem *selected_tree_item = terrains_tree->get_selected();
+	if (selected_tree_item && selected_tree_item->get_metadata(0)) {
+		Dictionary metadata_dict = selected_tree_item->get_metadata(0);
+		int selected_terrain_set = metadata_dict["terrain_set"];
+		int selected_terrain_id = metadata_dict["terrain_id"];
+		ERR_FAIL_INDEX(selected_terrain_set, (int)per_terrain_terrains_tile_patterns.size());
+		ERR_FAIL_INDEX(selected_terrain_id, (int)per_terrain_terrains_tile_patterns[selected_terrain_set].size());
+
+		// Sort the items in a map by the number of corresponding terrains.
+		Map<int, Set<TerrainsTilePattern>> sorted;
+		for (Set<TerrainsTilePattern>::Element *E = per_terrain_terrains_tile_patterns[selected_terrain_set][selected_terrain_id].front(); E; E = E->next()) {
+			// Count the number of matching sides/terrains.
+			int count = 0;
+
+			for (int i = 0; i < E->get().size(); i++) {
+				if (int(E->get()[i]) == selected_terrain_id) {
+					count++;
+				}
+			}
+			sorted[count].insert(E->get());
+		}
+
+		for (Map<int, Set<TerrainsTilePattern>>::Element *E_set = sorted.back(); E_set; E_set = E_set->prev()) {
+			for (Set<TerrainsTilePattern>::Element *E = E_set->get().front(); E; E = E->next()) {
+				TerrainsTilePattern terrains_tile_pattern = E->get();
+
+				// Get the icon.
+				Ref<Texture2D> icon;
+				Rect2 region;
+				bool transpose = false;
+
+				double max_probability = -1.0;
+				for (Set<TileMapCell>::Element *E_tile_map_cell = per_terrain_terrains_tile_patterns_tiles[selected_terrain_set][terrains_tile_pattern].front(); E_tile_map_cell; E_tile_map_cell = E_tile_map_cell->next()) {
+					Ref<TileSetSource> source = tile_set->get_source(E_tile_map_cell->get().source_id);
+
+					Ref<TileSetAtlasSource> atlas_source = source;
+					if (atlas_source.is_valid()) {
+						TileData *tile_data = Object::cast_to<TileData>(atlas_source->get_tile_data(E_tile_map_cell->get().get_atlas_coords(), E_tile_map_cell->get().alternative_tile));
+						if (tile_data->get_probability() > max_probability) {
+							icon = atlas_source->get_texture();
+							region = atlas_source->get_tile_texture_region(E_tile_map_cell->get().get_atlas_coords());
+							if (tile_data->get_flip_h()) {
+								region.position.x += region.size.x;
+								region.size.x = -region.size.x;
+							}
+							if (tile_data->get_flip_v()) {
+								region.position.y += region.size.y;
+								region.size.y = -region.size.y;
+							}
+							transpose = tile_data->get_transpose();
+							max_probability = tile_data->get_probability();
+						}
+					}
+				}
+
+				// Create the ItemList's item.
+				int item_index = terrains_tile_list->add_item("");
+				terrains_tile_list->set_item_icon(item_index, icon);
+				terrains_tile_list->set_item_icon_region(item_index, region);
+				terrains_tile_list->set_item_icon_transposed(item_index, transpose);
+				Dictionary list_metadata_dict;
+				list_metadata_dict["terrains_tile_pattern"] = terrains_tile_pattern;
+				terrains_tile_list->set_item_metadata(item_index, list_metadata_dict);
+			}
+		}
+		if (terrains_tile_list->get_item_count() > 0) {
+			terrains_tile_list->select(0);
+		}
+	}
+}
+
+void TileMapEditorTerrainsPlugin::edit(ObjectID p_tile_map_id) {
+	tile_map_id = p_tile_map_id;
+	_update_terrains_cache();
+	_update_terrains_tree();
+	_update_tiles_list();
+}
+
+TileMapEditorTerrainsPlugin::TileMapEditorTerrainsPlugin() {
+	set_name("Terrains");
+
+	HSplitContainer *tilemap_tab_terrains = memnew(HSplitContainer);
+	tilemap_tab_terrains->set_h_size_flags(SIZE_EXPAND_FILL);
+	tilemap_tab_terrains->set_v_size_flags(SIZE_EXPAND_FILL);
+	add_child(tilemap_tab_terrains);
+
+	terrains_tree = memnew(Tree);
+	terrains_tree->set_h_size_flags(SIZE_EXPAND_FILL);
+	terrains_tree->set_stretch_ratio(0.25);
+	terrains_tree->set_custom_minimum_size(Size2i(70, 0) * EDSCALE);
+	terrains_tree->set_texture_filter(CanvasItem::TEXTURE_FILTER_NEAREST);
+	terrains_tree->set_hide_root(true);
+	terrains_tree->connect("item_selected", callable_mp(this, &TileMapEditorTerrainsPlugin::_update_tiles_list));
+	tilemap_tab_terrains->add_child(terrains_tree);
+
+	terrains_tile_list = memnew(ItemList);
+	terrains_tile_list->set_h_size_flags(SIZE_EXPAND_FILL);
+	terrains_tile_list->set_max_columns(0);
+	terrains_tile_list->set_same_column_width(true);
+	terrains_tile_list->set_fixed_icon_size(Size2(30, 30) * EDSCALE);
+	terrains_tile_list->set_texture_filter(CanvasItem::TEXTURE_FILTER_NEAREST);
+	tilemap_tab_terrains->add_child(terrains_tile_list);
+
+	// --- Toolbar ---
+	toolbar = memnew(HBoxContainer);
+
+	HBoxContainer *tilemap_tiles_tools_buttons = memnew(HBoxContainer);
+
+	tool_buttons_group.instance();
+
+	paint_tool_button = memnew(Button);
+	paint_tool_button->set_flat(true);
+	paint_tool_button->set_toggle_mode(true);
+	paint_tool_button->set_button_group(tool_buttons_group);
+	paint_tool_button->set_pressed(true);
+	paint_tool_button->set_shortcut(ED_SHORTCUT("tiles_editor/paint_tool", "Paint", KEY_E));
+	paint_tool_button->connect("pressed", callable_mp(this, &TileMapEditorTerrainsPlugin::_update_toolbar));
+	tilemap_tiles_tools_buttons->add_child(paint_tool_button);
+
+	toolbar->add_child(tilemap_tiles_tools_buttons);
+
+	// -- TileMap tool settings --
+	tools_settings = memnew(HBoxContainer);
+	toolbar->add_child(tools_settings);
+
+	tools_settings_vsep = memnew(VSeparator);
+	tools_settings->add_child(tools_settings_vsep);
+
+	// Picker
+	picker_button = memnew(Button);
+	picker_button->set_flat(true);
+	picker_button->set_toggle_mode(true);
+	picker_button->set_shortcut(ED_SHORTCUT("tiles_editor/picker", "Picker", KEY_P));
+	picker_button->connect("pressed", callable_mp(CanvasItemEditor::get_singleton(), &CanvasItemEditor::update_viewport));
+	tools_settings->add_child(picker_button);
+
+	// Erase button.
+	erase_button = memnew(Button);
+	erase_button->set_flat(true);
+	erase_button->set_toggle_mode(true);
+	erase_button->set_shortcut(ED_SHORTCUT("tiles_editor/eraser", "Eraser", KEY_E));
+	erase_button->connect("pressed", callable_mp(CanvasItemEditor::get_singleton(), &CanvasItemEditor::update_viewport));
+	tools_settings->add_child(erase_button);
+}
+
+TileMapEditorTerrainsPlugin::~TileMapEditorTerrainsPlugin() {
+}
+
+void TileMapEditor::_notification(int p_what) {
+	switch (p_what) {
+		case NOTIFICATION_ENTER_TREE:
+		case NOTIFICATION_THEME_CHANGED:
+			missing_tile_texture = get_theme_icon("StatusWarning", "EditorIcons");
+			warning_pattern_texture = get_theme_icon("WarningPattern", "EditorIcons");
+			break;
+		case NOTIFICATION_INTERNAL_PROCESS:
+			if (is_visible_in_tree() && tileset_changed_needs_update) {
+				_update_bottom_panel();
+				tile_map_editor_plugins[tabs->get_current_tab()]->tile_set_changed();
+				CanvasItemEditor::get_singleton()->update_viewport();
+				tileset_changed_needs_update = false;
+			}
+			break;
+	}
+}
+
+void TileMapEditor::_update_bottom_panel() {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+
+	// Update the visibility of controls.
+	missing_tileset_label->set_visible(!tile_set.is_valid());
+	if (!tile_set.is_valid()) {
+		for (int i = 0; i < tile_map_editor_plugins.size(); i++) {
+			tile_map_editor_plugins[i]->hide();
+		}
+	} else {
+		for (int i = 0; i < tile_map_editor_plugins.size(); i++) {
+			tile_map_editor_plugins[i]->set_visible(i == tabs->get_current_tab());
+		}
+	}
+}
+
+Vector<Vector2i> TileMapEditor::get_line(TileMap *p_tile_map, Vector2i p_from_cell, Vector2i p_to_cell) {
+	ERR_FAIL_COND_V(!p_tile_map, Vector<Vector2i>());
+
+	Ref<TileSet> tile_set = p_tile_map->get_tileset();
+	ERR_FAIL_COND_V(!tile_set.is_valid(), Vector<Vector2i>());
+
+	if (tile_set->get_tile_shape() == TileSet::TILE_SHAPE_SQUARE) {
+		return Geometry2D::bresenham_line(p_from_cell, p_to_cell);
+	} else {
+		// Adapt the bresenham line algorithm to half-offset shapes.
+		// See this blog post: http://zvold.blogspot.com/2010/01/bresenhams-line-drawing-algorithm-on_26.html
+		Vector<Point2i> points;
+
+		bool transposed = tile_set->get_tile_offset_axis() == TileSet::TILE_OFFSET_AXIS_VERTICAL;
+		p_from_cell = TileMap::transform_coords_layout(p_from_cell, tile_set->get_tile_offset_axis(), tile_set->get_tile_layout(), TileSet::TILE_LAYOUT_STACKED);
+		p_to_cell = TileMap::transform_coords_layout(p_to_cell, tile_set->get_tile_offset_axis(), tile_set->get_tile_layout(), TileSet::TILE_LAYOUT_STACKED);
+		if (transposed) {
+			SWAP(p_from_cell.x, p_from_cell.y);
+			SWAP(p_to_cell.x, p_to_cell.y);
+		}
+
+		Vector2i delta = p_to_cell - p_from_cell;
+		delta = Vector2i(2 * delta.x + ABS(p_to_cell.y % 2) - ABS(p_from_cell.y % 2), delta.y);
+		Vector2i sign = delta.sign();
+
+		Vector2i current = p_from_cell;
+		points.push_back(TileMap::transform_coords_layout(transposed ? Vector2i(current.y, current.x) : current, tile_set->get_tile_offset_axis(), TileSet::TILE_LAYOUT_STACKED, tile_set->get_tile_layout()));
+
+		int err = 0;
+		if (ABS(delta.y) < ABS(delta.x)) {
+			Vector2i err_step = 3 * delta.abs();
+			while (current != p_to_cell) {
+				err += err_step.y;
+				if (err > ABS(delta.x)) {
+					if (sign.x == 0) {
+						current += Vector2(sign.y, 0);
+					} else {
+						current += Vector2(bool(current.y % 2) ^ (sign.x < 0) ? sign.x : 0, sign.y);
+					}
+					err -= err_step.x;
+				} else {
+					current += Vector2i(sign.x, 0);
+					err += err_step.y;
+				}
+				points.push_back(TileMap::transform_coords_layout(transposed ? Vector2i(current.y, current.x) : current, tile_set->get_tile_offset_axis(), TileSet::TILE_LAYOUT_STACKED, tile_set->get_tile_layout()));
+			}
+		} else {
+			Vector2i err_step = delta.abs();
+			while (current != p_to_cell) {
+				err += err_step.x;
+				if (err > 0) {
+					if (sign.x == 0) {
+						current += Vector2(0, sign.y);
+					} else {
+						current += Vector2(bool(current.y % 2) ^ (sign.x < 0) ? sign.x : 0, sign.y);
+					}
+					err -= err_step.y;
+				} else {
+					if (sign.x == 0) {
+						current += Vector2(0, sign.y);
+					} else {
+						current += Vector2(bool(current.y % 2) ^ (sign.x > 0) ? -sign.x : 0, sign.y);
+					}
+					err += err_step.y;
+				}
+				points.push_back(TileMap::transform_coords_layout(transposed ? Vector2i(current.y, current.x) : current, tile_set->get_tile_offset_axis(), TileSet::TILE_LAYOUT_STACKED, tile_set->get_tile_layout()));
+			}
+		}
+
+		return points;
+	}
+}
+
+void TileMapEditor::_tile_map_changed() {
+	tileset_changed_needs_update = true;
+}
+
+void TileMapEditor::_tab_changed(int p_tab_id) {
+	// Make the plugin edit the correct tilemap.
+	tile_map_editor_plugins[tabs->get_current_tab()]->edit(tile_map_id);
+
+	// Update toolbar.
+	for (int i = 0; i < tile_map_editor_plugins.size(); i++) {
+		tile_map_editor_plugins[i]->get_toolbar()->set_visible(i == p_tab_id);
+	}
+
+	// Update visible panel.
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map || !tile_map->get_tileset().is_valid()) {
+		for (int i = 0; i < tile_map_editor_plugins.size(); i++) {
+			tile_map_editor_plugins[i]->hide();
+		}
+	} else {
+		for (int i = 0; i < tile_map_editor_plugins.size(); i++) {
+			tile_map_editor_plugins[i]->set_visible(i == tabs->get_current_tab());
+		}
+	}
+
+	// Graphical update.
+	tile_map_editor_plugins[tabs->get_current_tab()]->update();
+	CanvasItemEditor::get_singleton()->update_viewport();
+}
+
+bool TileMapEditor::forward_canvas_gui_input(const Ref<InputEvent> &p_event) {
+	return tile_map_editor_plugins[tabs->get_current_tab()]->forward_canvas_gui_input(p_event);
+}
+
+void TileMapEditor::forward_canvas_draw_over_viewport(Control *p_overlay) {
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (!tile_map) {
+		return;
+	}
+
+	Ref<TileSet> tile_set = tile_map->get_tileset();
+	if (!tile_set.is_valid()) {
+		return;
+	}
+
+	if (!tile_map->is_visible_in_tree()) {
+		return;
+	}
+
+	Transform2D xform = CanvasItemEditor::get_singleton()->get_canvas_transform() * tile_map->get_global_transform();
+	Transform2D xform_inv = xform.affine_inverse();
+	Vector2i tile_shape_size = tile_set->get_tile_size();
+
+	// Draw tiles with invalid IDs in the grid.
+	float icon_ratio = MIN(missing_tile_texture->get_size().x / tile_set->get_tile_size().x, missing_tile_texture->get_size().y / tile_set->get_tile_size().y) / 3;
+	TypedArray<Vector2i> used_cells = tile_map->get_used_cells();
+	for (int i = 0; i < used_cells.size(); i++) {
+		Vector2i coords = used_cells[i];
+		int tile_source_id = tile_map->get_cell_source_id(coords);
+		if (tile_source_id >= 0) {
+			Vector2i tile_atlas_coords = tile_map->get_cell_atlas_coords(coords);
+			int tile_alternative_tile = tile_map->get_cell_alternative_tile(coords);
+
+			TileSetSource *source = nullptr;
+			if (tile_set->has_source(tile_source_id)) {
+				source = *tile_set->get_source(tile_source_id);
+			}
+
+			if (!source || !source->has_tile(tile_atlas_coords) || !source->has_alternative_tile(tile_atlas_coords, tile_alternative_tile)) {
+				// Generate a random color from the hashed values of the tiles.
+				Array to_hash;
+				to_hash.push_back(tile_source_id);
+				to_hash.push_back(tile_atlas_coords);
+				to_hash.push_back(tile_alternative_tile);
+				uint32_t hash = RandomPCG(to_hash.hash()).rand();
+
+				Color color;
+				color = color.from_hsv(
+						(float)((hash >> 24) & 0xFF) / 256.0,
+						Math::lerp(0.5, 1.0, (float)((hash >> 16) & 0xFF) / 256.0),
+						Math::lerp(0.5, 1.0, (float)((hash >> 8) & 0xFF) / 256.0),
+						0.8);
+
+				// Draw the scaled tile.
+				Rect2 cell_region = xform.xform(Rect2(tile_map->map_to_world(coords) - Vector2(tile_shape_size) / 2, Vector2(tile_shape_size)));
+				tile_set->draw_tile_shape(p_overlay, cell_region, color, true, warning_pattern_texture);
+
+				// Draw the warning icon.
+				Rect2 rect = Rect2(xform.xform(tile_map->map_to_world(coords)) - (icon_ratio * missing_tile_texture->get_size() * xform.get_scale() / 2), icon_ratio * missing_tile_texture->get_size() * xform.get_scale());
+				p_overlay->draw_texture_rect(missing_tile_texture, rect);
+			}
+		}
+	}
+
+	// Fading on the border.
+	const int fading = 5;
+
+	// Determine the drawn area.
+	Size2 screen_size = p_overlay->get_size();
+	Rect2i screen_rect;
+	screen_rect.position = tile_map->world_to_map(xform_inv.xform(Vector2()));
+	screen_rect.expand_to(tile_map->world_to_map(xform_inv.xform(Vector2(0, screen_size.height))));
+	screen_rect.expand_to(tile_map->world_to_map(xform_inv.xform(Vector2(screen_size.width, 0))));
+	screen_rect.expand_to(tile_map->world_to_map(xform_inv.xform(screen_size)));
+	screen_rect = screen_rect.grow(1);
+
+	Rect2i tilemap_used_rect = tile_map->get_used_rect();
+
+	Rect2i displayed_rect = tilemap_used_rect.intersection(screen_rect);
+	displayed_rect = displayed_rect.grow(fading);
+
+	// Reduce the drawn area to avoid crashes if needed.
+	int max_size = 100;
+	if (displayed_rect.size.x > max_size) {
+		displayed_rect = displayed_rect.grow_individual(-(displayed_rect.size.x - max_size) / 2, 0, -(displayed_rect.size.x - max_size) / 2, 0);
+	}
+	if (displayed_rect.size.y > max_size) {
+		displayed_rect = displayed_rect.grow_individual(0, -(displayed_rect.size.y - max_size) / 2, 0, -(displayed_rect.size.y - max_size) / 2);
+	}
+
+	// Draw the grid.
+	for (int x = displayed_rect.position.x; x < (displayed_rect.position.x + displayed_rect.size.x); x++) {
+		for (int y = displayed_rect.position.y; y < (displayed_rect.position.y + displayed_rect.size.y); y++) {
+			Vector2i pos_in_rect = Vector2i(x, y) - displayed_rect.position;
+
+			// Fade out the border of the grid.
+			float left_opacity = CLAMP(Math::inverse_lerp(0.0f, (float)fading, (float)pos_in_rect.x), 0.0f, 1.0f);
+			float right_opacity = CLAMP(Math::inverse_lerp((float)displayed_rect.size.x, (float)(displayed_rect.size.x - fading), (float)pos_in_rect.x), 0.0f, 1.0f);
+			float top_opacity = CLAMP(Math::inverse_lerp(0.0f, (float)fading, (float)pos_in_rect.y), 0.0f, 1.0f);
+			float bottom_opacity = CLAMP(Math::inverse_lerp((float)displayed_rect.size.y, (float)(displayed_rect.size.y - fading), (float)pos_in_rect.y), 0.0f, 1.0f);
+			float opacity = CLAMP(MIN(left_opacity, MIN(right_opacity, MIN(top_opacity, bottom_opacity))) + 0.1, 0.0f, 1.0f);
+
+			Rect2 cell_region = xform.xform(Rect2(tile_map->map_to_world(Vector2(x, y)) - tile_shape_size / 2, tile_shape_size));
+			tile_set->draw_tile_shape(p_overlay, cell_region, Color(1.0, 0.5, 0.2, 0.5 * opacity), false);
+		}
+	}
+
+	// Draw the IDs for debug.
+	/*Ref<Font> font = get_theme_font("font", "Label");
+	for (int x = displayed_rect.position.x; x < (displayed_rect.position.x + displayed_rect.size.x); x++) {
+		for (int y = displayed_rect.position.y; y < (displayed_rect.position.y + displayed_rect.size.y); y++) {
+			p_overlay->draw_string(font, xform.xform(tile_map->map_to_world(Vector2(x, y))) + Vector2i(-tile_shape_size.x / 2, 0), vformat("%s", Vector2(x, y)));
+		}
+	}*/
+
+	// Draw the plugins.
+	tile_map_editor_plugins[tabs->get_current_tab()]->forward_canvas_draw_over_viewport(p_overlay);
+}
+
+void TileMapEditor::edit(TileMap *p_tile_map) {
+	if (p_tile_map && p_tile_map->get_instance_id() == tile_map_id) {
+		return;
+	}
+
+	// Disconnect to changes.
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (tile_map) {
+		tile_map->disconnect("changed", callable_mp(this, &TileMapEditor::_tile_map_changed));
+	}
+
+	// Change the edited object.
+	if (p_tile_map) {
+		tile_map_id = p_tile_map->get_instance_id();
+		tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+		// Connect to changes.
+		if (!tile_map->is_connected("changed", callable_mp(this, &TileMapEditor::_tile_map_changed))) {
+			tile_map->connect("changed", callable_mp(this, &TileMapEditor::_tile_map_changed));
+		}
+	} else {
+		tile_map_id = ObjectID();
+	}
+
+	// Call the plugins.
+	tile_map_editor_plugins[tabs->get_current_tab()]->edit(tile_map_id);
+
+	_tile_map_changed();
+}
+
+TileMapEditor::TileMapEditor() {
+	set_process_internal(true);
+
+	// TileMap editor plugins
+	tile_map_editor_plugins.push_back(memnew(TileMapEditorTilesPlugin));
+	tile_map_editor_plugins.push_back(memnew(TileMapEditorTerrainsPlugin));
+
+	// Tabs.
+	tabs = memnew(Tabs);
+	tabs->set_clip_tabs(false);
+	for (int i = 0; i < tile_map_editor_plugins.size(); i++) {
+		tabs->add_tab(tile_map_editor_plugins[i]->get_name());
+	}
+	tabs->connect("tab_changed", callable_mp(this, &TileMapEditor::_tab_changed));
+
+	// --- TileMap toolbar ---
+	tilemap_toolbar = memnew(HBoxContainer);
+	//tilemap_toolbar->add_child(memnew(VSeparator));
+	tilemap_toolbar->add_child(tabs);
+	//tilemap_toolbar->add_child(memnew(VSeparator));
+	for (int i = 0; i < tile_map_editor_plugins.size(); i++) {
+		tile_map_editor_plugins[i]->get_toolbar()->hide();
+		tilemap_toolbar->add_child(tile_map_editor_plugins[i]->get_toolbar());
+	}
+
+	missing_tileset_label = memnew(Label);
+	missing_tileset_label->set_text(TTR("The edited TileMap node has no TileSet resource."));
+	missing_tileset_label->set_h_size_flags(SIZE_EXPAND_FILL);
+	missing_tileset_label->set_v_size_flags(SIZE_EXPAND_FILL);
+	missing_tileset_label->set_align(Label::ALIGN_CENTER);
+	missing_tileset_label->set_valign(Label::VALIGN_CENTER);
+	missing_tileset_label->hide();
+	add_child(missing_tileset_label);
+
+	for (int i = 0; i < tile_map_editor_plugins.size(); i++) {
+		add_child(tile_map_editor_plugins[i]);
+		tile_map_editor_plugins[i]->set_h_size_flags(SIZE_EXPAND_FILL);
+		tile_map_editor_plugins[i]->set_v_size_flags(SIZE_EXPAND_FILL);
+		tile_map_editor_plugins[i]->set_visible(i == 0);
+	}
+
+	_tab_changed(0);
+}
+
+TileMapEditor::~TileMapEditor() {
+}
diff --git a/editor/plugins/tiles/tile_map_editor.h b/editor/plugins/tiles/tile_map_editor.h
new file mode 100644
index 0000000000..f780686b82
--- /dev/null
+++ b/editor/plugins/tiles/tile_map_editor.h
@@ -0,0 +1,328 @@
+/*************************************************************************/
+/*  tile_map_editor.h                                                    */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef TILE_MAP_EDITOR_H
+#define TILE_MAP_EDITOR_H
+
+#include "tile_atlas_view.h"
+
+#include "core/typedefs.h"
+#include "editor/editor_node.h"
+#include "scene/2d/tile_map.h"
+#include "scene/gui/box_container.h"
+#include "scene/gui/tabs.h"
+
+class TileMapEditorPlugin : public VBoxContainer {
+public:
+	virtual Control *get_toolbar() const {
+		return memnew(Control);
+	};
+	virtual bool forward_canvas_gui_input(const Ref<InputEvent> &p_event) { return false; };
+	virtual void forward_canvas_draw_over_viewport(Control *p_overlay){};
+	virtual void tile_set_changed(){};
+	virtual void edit(ObjectID p_tile_map_id){};
+};
+
+class TileMapEditorTilesPlugin : public TileMapEditorPlugin {
+	GDCLASS(TileMapEditorTilesPlugin, TileMapEditorPlugin);
+
+private:
+	UndoRedo *undo_redo = EditorNode::get_undo_redo();
+	ObjectID tile_map_id;
+	virtual void edit(ObjectID p_tile_map_id) override;
+
+	// Toolbar.
+	HBoxContainer *toolbar;
+
+	Ref<ButtonGroup> tool_buttons_group;
+	Button *select_tool_button;
+	Button *paint_tool_button;
+	Button *line_tool_button;
+	Button *rect_tool_button;
+	Button *bucket_tool_button;
+	Button *picker_button;
+
+	HBoxContainer *tools_settings;
+	VSeparator *tools_settings_vsep;
+	Button *erase_button;
+	CheckBox *bucket_continuous_checkbox;
+
+	VSeparator *tools_settings_vsep_2;
+	CheckBox *random_tile_checkbox;
+	float scattering = 0.0;
+	Label *scatter_label;
+	SpinBox *scatter_spinbox;
+	void _on_random_tile_checkbox_toggled(bool p_pressed);
+	void _on_scattering_spinbox_changed(double p_value);
+
+	void _update_toolbar();
+
+	// Tilemap editing.
+	bool has_mouse = false;
+	void _mouse_exited_viewport();
+
+	enum DragType {
+		DRAG_TYPE_NONE = 0,
+		DRAG_TYPE_SELECT,
+		DRAG_TYPE_MOVE,
+		DRAG_TYPE_PAINT,
+		DRAG_TYPE_LINE,
+		DRAG_TYPE_RECT,
+		DRAG_TYPE_BUCKET,
+		DRAG_TYPE_PICK,
+		DRAG_TYPE_CLIPBOARD_PASTE,
+	};
+	DragType drag_type = DRAG_TYPE_NONE;
+	Vector2 drag_start_mouse_pos;
+	Vector2 drag_last_mouse_pos;
+	Map<Vector2i, TileMapCell> drag_modified;
+
+	TileMapCell _pick_random_tile(const TileMapPattern *p_pattern);
+	Map<Vector2i, TileMapCell> _draw_line(Vector2 p_start_drag_mouse_pos, Vector2 p_from_mouse_pos, Vector2i p_to_mouse_pos);
+	Map<Vector2i, TileMapCell> _draw_rect(Vector2i p_start_mouse_pos, Vector2i p_end_mouse_pos);
+	Map<Vector2i, TileMapCell> _draw_bucket_fill(Vector2i p_coords, bool p_contiguous);
+	void _stop_dragging();
+
+	// Selection system.
+	Set<Vector2i> tile_map_selection;
+	TileMapPattern *tile_map_clipboard = memnew(TileMapPattern);
+	TileMapPattern *selection_pattern = memnew(TileMapPattern);
+	void _set_tile_map_selection(const TypedArray<Vector2i> &p_selection);
+	TypedArray<Vector2i> _get_tile_map_selection() const;
+
+	Set<TileMapCell> tile_set_selection;
+
+	void _update_selection_pattern_from_tilemap_selection();
+	void _update_selection_pattern_from_tileset_selection();
+	void _update_tileset_selection_from_selection_pattern();
+	void _update_fix_selected_and_hovered();
+
+	// Bottom panel.
+	bool tile_set_dragging_selection = false;
+	Vector2i tile_set_drag_start_mouse_pos;
+
+	Label *missing_source_label;
+	HSplitContainer *atlas_sources_split_container;
+
+	ItemList *sources_list;
+	TileAtlasView *tile_atlas_view;
+	Ref<Texture2D> missing_texture_texture;
+	void _update_tile_set_sources_list();
+	void _update_atlas_view();
+
+	void _update_bottom_panel();
+
+	TileMapCell hovered_tile;
+
+	Control *tile_atlas_control;
+	void _tile_atlas_control_mouse_exited();
+	void _tile_atlas_control_gui_input(const Ref<InputEvent> &p_event);
+	void _tile_atlas_control_draw();
+
+	Control *alternative_tiles_control;
+	void _tile_alternatives_control_draw();
+	void _tile_alternatives_control_mouse_exited();
+	void _tile_alternatives_control_gui_input(const Ref<InputEvent> &p_event);
+
+	// Update callback
+	virtual void tile_set_changed() override;
+
+protected:
+	void _notification(int p_what);
+	static void _bind_methods();
+
+public:
+	virtual Control *get_toolbar() const override;
+	virtual bool forward_canvas_gui_input(const Ref<InputEvent> &p_event) override;
+	virtual void forward_canvas_draw_over_viewport(Control *p_overlay) override;
+
+	TileMapEditorTilesPlugin();
+	~TileMapEditorTilesPlugin();
+};
+
+class TileMapEditorTerrainsPlugin : public TileMapEditorPlugin {
+	GDCLASS(TileMapEditorTerrainsPlugin, TileMapEditorPlugin);
+
+private:
+	UndoRedo *undo_redo = EditorNode::get_undo_redo();
+	ObjectID tile_map_id;
+	virtual void edit(ObjectID p_tile_map_id) override;
+
+	// Toolbar.
+	HBoxContainer *toolbar;
+
+	Ref<ButtonGroup> tool_buttons_group;
+	Button *paint_tool_button;
+
+	HBoxContainer *tools_settings;
+	VSeparator *tools_settings_vsep;
+	Button *picker_button;
+	Button *erase_button;
+
+	void _update_toolbar();
+
+	// TileMap editing.
+	enum DragType {
+		DRAG_TYPE_NONE = 0,
+		DRAG_TYPE_PAINT,
+		DRAG_TYPE_PICK,
+	};
+	DragType drag_type = DRAG_TYPE_NONE;
+	Vector2 drag_start_mouse_pos;
+	Vector2 drag_last_mouse_pos;
+	Map<Vector2i, TileMapCell> drag_modified;
+
+	// Painting
+	class Constraint {
+	private:
+		const TileMap *tile_map;
+		Vector2i base_cell_coords = Vector2i();
+		int bit = -1;
+		int terrain = -1;
+
+	public:
+		// TODO implement difference operator.
+		bool operator<(const Constraint &p_other) const {
+			if (base_cell_coords == p_other.base_cell_coords) {
+				return bit < p_other.bit;
+			}
+			return base_cell_coords < p_other.base_cell_coords;
+		}
+
+		String to_string() const {
+			return vformat("Constraint {pos:%s, bit:%d, terrain:%d}", base_cell_coords, bit, terrain);
+		}
+
+		Vector2i get_base_cell_coords() const {
+			return base_cell_coords;
+		}
+
+		Map<Vector2i, TileSet::CellNeighbor> get_overlapping_coords_and_peering_bits() const;
+
+		void set_terrain(int p_terrain) {
+			terrain = p_terrain;
+		}
+
+		int get_terrain() const {
+			return terrain;
+		}
+
+		Constraint(const TileMap *p_tile_map, const Vector2i &p_position, const TileSet::CellNeighbor &p_bit, int p_terrain);
+		Constraint() {}
+	};
+
+	typedef Array TerrainsTilePattern;
+
+	Set<TerrainsTilePattern> _get_valid_terrains_tile_patterns_for_constraints(int p_terrain_set, const Vector2i &p_position, Set<TileMapEditorTerrainsPlugin::Constraint> p_constraints) const;
+	Set<TileMapEditorTerrainsPlugin::Constraint> _get_constraints_from_removed_cells_list(const Set<Vector2i> &p_to_replace, int p_terrain_set) const;
+	Set<TileMapEditorTerrainsPlugin::Constraint> _get_constraints_from_added_tile(Vector2i p_position, int p_terrain_set, TerrainsTilePattern p_terrains_tile_pattern) const;
+	Map<Vector2i, TerrainsTilePattern> _wave_function_collapse(const Set<Vector2i> &p_to_replace, int p_terrain_set, const Set<TileMapEditorTerrainsPlugin::Constraint> p_constraints) const;
+	TileMapCell _get_random_tile_from_pattern(int p_terrain_set, TerrainsTilePattern p_terrain_tile_pattern) const;
+	Map<Vector2i, TileMapCell> _draw_terrains(const Map<Vector2i, TerrainsTilePattern> &p_to_paint, int p_terrain_set) const;
+
+	// Cached data.
+
+	TerrainsTilePattern _build_terrains_tile_pattern(TileData *p_tile_data);
+	LocalVector<Map<TerrainsTilePattern, Set<TileMapCell>>> per_terrain_terrains_tile_patterns_tiles;
+	LocalVector<LocalVector<Set<TerrainsTilePattern>>> per_terrain_terrains_tile_patterns;
+
+	Map<TileMapCell, TileData *> terrain_tiles;
+	LocalVector<TileSet::CellNeighbor> tile_sides;
+
+	// Bottom panel.
+	Tree *terrains_tree;
+	ItemList *terrains_tile_list;
+
+	// Update functions.
+	void _update_terrains_cache();
+	void _update_terrains_tree();
+	void _update_tiles_list();
+
+	// Update callback
+	virtual void tile_set_changed() override;
+
+protected:
+	void _notification(int p_what);
+	//	static void _bind_methods();
+
+public:
+	virtual Control *get_toolbar() const override;
+	virtual bool forward_canvas_gui_input(const Ref<InputEvent> &p_event) override;
+	//virtual void forward_canvas_draw_over_viewport(Control *p_overlay) override;
+
+	TileMapEditorTerrainsPlugin();
+	~TileMapEditorTerrainsPlugin();
+};
+
+class TileMapEditor : public VBoxContainer {
+	GDCLASS(TileMapEditor, VBoxContainer);
+
+private:
+	bool tileset_changed_needs_update = false;
+	ObjectID tile_map_id;
+
+	// Vector to keep plugins.
+	Vector<TileMapEditorPlugin *> tile_map_editor_plugins;
+
+	// Toolbar.
+	HBoxContainer *tilemap_toolbar;
+
+	// Bottom panel
+	Label *missing_tileset_label;
+	Tabs *tabs;
+	void _update_bottom_panel();
+
+	// TileMap
+	Ref<Texture2D> missing_tile_texture;
+	Ref<Texture2D> warning_pattern_texture;
+
+	// CallBack
+	void _tile_map_changed();
+	void _tab_changed(int p_tab_changed);
+
+protected:
+	void _notification(int p_what);
+	void _draw_shape(Control *p_control, Rect2 p_region, TileSet::TileShape p_shape, TileSet::TileOffsetAxis p_offset_axis, Color p_color);
+
+public:
+	bool forward_canvas_gui_input(const Ref<InputEvent> &p_event);
+	void forward_canvas_draw_over_viewport(Control *p_overlay);
+
+	void edit(TileMap *p_tile_map);
+	Control *get_toolbar() { return tilemap_toolbar; };
+
+	TileMapEditor();
+	~TileMapEditor();
+
+	// Static functions.
+	static Vector<Vector2i> get_line(TileMap *p_tile_map, Vector2i p_from_cell, Vector2i p_to_cell);
+};
+
+#endif // TILE_MAP_EDITOR_PLUGIN_H
diff --git a/editor/plugins/tiles/tile_set_atlas_source_editor.cpp b/editor/plugins/tiles/tile_set_atlas_source_editor.cpp
new file mode 100644
index 0000000000..8492202122
--- /dev/null
+++ b/editor/plugins/tiles/tile_set_atlas_source_editor.cpp
@@ -0,0 +1,1858 @@
+/*************************************************************************/
+/*  tile_set_atlas_source_editor.cpp                                     */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "tile_set_atlas_source_editor.h"
+
+#include "tiles_editor_plugin.h"
+
+#include "editor/editor_inspector.h"
+#include "editor/editor_scale.h"
+#include "editor/progress_dialog.h"
+
+#include "scene/gui/box_container.h"
+#include "scene/gui/button.h"
+#include "scene/gui/control.h"
+#include "scene/gui/item_list.h"
+#include "scene/gui/separator.h"
+#include "scene/gui/split_container.h"
+#include "scene/gui/tab_container.h"
+
+#include "core/core_string_names.h"
+#include "core/math/geometry_2d.h"
+#include "core/os/keyboard.h"
+
+void TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::set_id(int p_id) {
+	ERR_FAIL_COND(p_id < 0);
+	if (source_id == p_id) {
+		return;
+	}
+	ERR_FAIL_COND_MSG(tile_set->has_source(p_id), vformat("Cannot change TileSet atlas source ID. Another atlas source exists with id %d.", p_id));
+
+	int previous_source = source_id;
+	source_id = p_id; // source_id must be updated before, because it's used by the atlas source list update.
+	tile_set->set_source_id(previous_source, p_id);
+	emit_signal("changed", "id");
+}
+
+int TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::get_id() {
+	return source_id;
+}
+
+bool TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::_set(const StringName &p_name, const Variant &p_value) {
+	bool valid = false;
+	tile_set_atlas_source->set(p_name, p_value, &valid);
+	if (valid) {
+		emit_signal("changed", String(p_name).utf8().get_data());
+	}
+	return valid;
+}
+
+bool TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::_get(const StringName &p_name, Variant &r_ret) const {
+	if (!tile_set_atlas_source) {
+		return false;
+	}
+	bool valid = false;
+	r_ret = tile_set_atlas_source->get(p_name, &valid);
+	return valid;
+}
+
+void TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::_get_property_list(List<PropertyInfo> *p_list) const {
+	p_list->push_back(PropertyInfo(Variant::OBJECT, "texture", PROPERTY_HINT_RESOURCE_TYPE, "Texture2D"));
+	p_list->push_back(PropertyInfo(Variant::VECTOR2I, "margins", PROPERTY_HINT_NONE, ""));
+	p_list->push_back(PropertyInfo(Variant::VECTOR2I, "separation", PROPERTY_HINT_NONE, ""));
+	p_list->push_back(PropertyInfo(Variant::VECTOR2I, "tile_size", PROPERTY_HINT_NONE, ""));
+}
+
+void TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::_bind_methods() {
+	// -- Shape and layout --
+	ClassDB::bind_method(D_METHOD("set_id", "id"), &TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::set_id);
+	ClassDB::bind_method(D_METHOD("get_id"), &TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::get_id);
+
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "id"), "set_id", "get_id");
+
+	ADD_SIGNAL(MethodInfo("changed", PropertyInfo(Variant::STRING, "what")));
+}
+
+void TileSetAtlasSourceEditor::TileSetAtlasSourceProxyObject::edit(Ref<TileSet> p_tile_set, TileSetAtlasSource *p_tile_set_atlas_source, int p_source_id) {
+	ERR_FAIL_COND(!p_tile_set.is_valid());
+	ERR_FAIL_COND(!p_tile_set_atlas_source);
+	ERR_FAIL_COND(p_source_id < 0);
+	ERR_FAIL_COND(p_tile_set->get_source(p_source_id) != p_tile_set_atlas_source);
+
+	// Disconnect to changes.
+	if (tile_set_atlas_source) {
+		tile_set_atlas_source->disconnect(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed));
+	}
+
+	tile_set = p_tile_set;
+	tile_set_atlas_source = p_tile_set_atlas_source;
+	source_id = p_source_id;
+
+	// Connect to changes.
+	if (tile_set_atlas_source) {
+		if (!tile_set_atlas_source->is_connected(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed))) {
+			tile_set_atlas_source->connect(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed));
+		}
+	}
+
+	notify_property_list_changed();
+}
+
+// -- Proxy object used by the tile inspector --
+bool TileSetAtlasSourceEditor::TileProxyObject::_set(const StringName &p_name, const Variant &p_value) {
+	if (!tile_set_atlas_source) {
+		return false;
+	}
+
+	if (tiles.size() == 1) {
+		const Vector2i &coords = tiles.front()->get().tile;
+		const int &alternative = tiles.front()->get().alternative;
+
+		if (alternative == 0 && p_name == "atlas_coords") {
+			Vector2i as_vector2i = Vector2i(p_value);
+			ERR_FAIL_COND_V(!tile_set_atlas_source->can_move_tile_in_atlas(coords, as_vector2i), false);
+
+			if (tiles_set_atlas_source_editor->selection.front()->get().tile == coords) {
+				tiles_set_atlas_source_editor->selection.clear();
+				tiles_set_atlas_source_editor->selection.insert({ as_vector2i, 0 });
+				tiles_set_atlas_source_editor->_update_tile_id_label();
+			}
+
+			tile_set_atlas_source->move_tile_in_atlas(coords, as_vector2i);
+			tiles.clear();
+			tiles.insert({ as_vector2i, 0 });
+			emit_signal("changed", "atlas_coords");
+			return true;
+		} else if (alternative == 0 && p_name == "size_in_atlas") {
+			Vector2i as_vector2i = Vector2i(p_value);
+			ERR_FAIL_COND_V(!tile_set_atlas_source->can_move_tile_in_atlas(coords, TileSetAtlasSource::INVALID_ATLAS_COORDS, as_vector2i), false);
+
+			tile_set_atlas_source->move_tile_in_atlas(coords, TileSetAtlasSource::INVALID_ATLAS_COORDS, as_vector2i);
+			emit_signal("changed", "size_in_atlas");
+			return true;
+		} else if (alternative > 0 && p_name == "alternative_id") {
+			int as_int = int(p_value);
+			ERR_FAIL_COND_V(as_int < 0, false);
+			ERR_FAIL_COND_V_MSG(tile_set_atlas_source->has_alternative_tile(coords, as_int), false, vformat("Cannot change alternative tile ID. Another alternative exists with id %d for tile at coords %s.", as_int, coords));
+
+			if (tiles_set_atlas_source_editor->selection.front()->get().alternative == alternative) {
+				tiles_set_atlas_source_editor->selection.clear();
+				tiles_set_atlas_source_editor->selection.insert({ coords, as_int });
+			}
+
+			int previous_alternative_tile = alternative;
+			tiles.clear();
+			tiles.insert({ coords, as_int }); // tiles must be updated before.
+			tile_set_atlas_source->set_alternative_tile_id(coords, previous_alternative_tile, as_int);
+
+			emit_signal("changed", "alternative_id");
+			return true;
+		}
+	}
+
+	bool any_valid = false;
+	for (Set<TileSelection>::Element *E = tiles.front(); E; E = E->next()) {
+		const Vector2i &coords = E->get().tile;
+		const int &alternative = E->get().alternative;
+
+		bool valid = false;
+		TileData *tile_data = Object::cast_to<TileData>(tile_set_atlas_source->get_tile_data(coords, alternative));
+		ERR_FAIL_COND_V(!tile_data, false);
+		tile_data->set(p_name, p_value, &valid);
+
+		any_valid |= valid;
+	}
+
+	if (any_valid) {
+		emit_signal("changed", String(p_name).utf8().get_data());
+	}
+
+	return any_valid;
+}
+
+bool TileSetAtlasSourceEditor::TileProxyObject::_get(const StringName &p_name, Variant &r_ret) const {
+	if (!tile_set_atlas_source) {
+		return false;
+	}
+
+	if (tiles.size() == 1) {
+		const Vector2i &coords = tiles.front()->get().tile;
+		const int &alternative = tiles.front()->get().alternative;
+
+		if (alternative == 0 && p_name == "atlas_coords") {
+			r_ret = coords;
+			return true;
+		} else if (alternative == 0 && p_name == "size_in_atlas") {
+			r_ret = tile_set_atlas_source->get_tile_size_in_atlas(coords);
+			return true;
+		} else if (alternative > 0 && p_name == "alternative_id") {
+			r_ret = alternative;
+			return true;
+		}
+	}
+
+	for (Set<TileSelection>::Element *E = tiles.front(); E; E = E->next()) {
+		// Return the first tile with a property matching the name.
+		// Note: It's a little bit annoying, but the behavior is the same the one in MultiNodeEdit.
+		const Vector2i &coords = E->get().tile;
+		const int &alternative = E->get().alternative;
+
+		TileData *tile_data = Object::cast_to<TileData>(tile_set_atlas_source->get_tile_data(coords, alternative));
+		ERR_FAIL_COND_V(!tile_data, false);
+
+		bool valid = false;
+		r_ret = tile_data->get(p_name, &valid);
+		if (valid) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
+void TileSetAtlasSourceEditor::TileProxyObject::_get_property_list(List<PropertyInfo> *p_list) const {
+	if (!tile_set_atlas_source) {
+		return;
+	}
+
+	if (tiles.size() == 1) {
+		if (tiles.front()->get().alternative == 0) {
+			p_list->push_back(PropertyInfo(Variant::VECTOR2I, "atlas_coords", PROPERTY_HINT_NONE, ""));
+			p_list->push_back(PropertyInfo(Variant::VECTOR2I, "size_in_atlas", PROPERTY_HINT_NONE, ""));
+		} else {
+			p_list->push_back(PropertyInfo(Variant::INT, "alternative_id", PROPERTY_HINT_NONE, ""));
+		}
+	}
+
+	// Get the list of properties common to all tiles (similar to what's done in MultiNodeEdit).
+	struct PropertyId {
+		int occurence_id = 0;
+		String property;
+		bool operator<(const PropertyId &p_other) const {
+			return occurence_id == p_other.occurence_id ? property < p_other.property : occurence_id < p_other.occurence_id;
+		}
+	};
+	struct PLData {
+		int uses = 0;
+		PropertyInfo property_info;
+	};
+	Map<PropertyId, PLData> usage;
+
+	List<PLData *> data_list;
+	for (Set<TileSelection>::Element *E = tiles.front(); E; E = E->next()) {
+		const Vector2i &coords = E->get().tile;
+		const int &alternative = E->get().alternative;
+
+		TileData *tile_data = Object::cast_to<TileData>(tile_set_atlas_source->get_tile_data(coords, alternative));
+		ERR_FAIL_COND(!tile_data);
+
+		List<PropertyInfo> list;
+		tile_data->get_property_list(&list);
+
+		Map<String, int> counts; // Counts the number of time a property appears (useful for groups that may appear more than once)
+		for (List<PropertyInfo>::Element *E_property = list.front(); E_property; E_property = E_property->next()) {
+			const String &property_string = E_property->get().name;
+			if (!tile_data->is_allowing_transform() && (property_string == "flip_h" || property_string == "flip_v" || property_string == "transpose")) {
+				continue;
+			}
+
+			if (!counts.has(property_string)) {
+				counts[property_string] = 1;
+			} else {
+				counts[property_string] += 1;
+			}
+
+			PropertyInfo stored_property_info = E_property->get();
+			stored_property_info.usage |= PROPERTY_USAGE_STORAGE; // Ignore the storage flag in comparing properties.
+
+			PropertyId id = { counts[property_string], property_string };
+			if (!usage.has(id)) {
+				usage[id] = { 1, stored_property_info };
+				data_list.push_back(&usage[id]);
+			} else if (usage[id].property_info == stored_property_info) {
+				usage[id].uses += 1;
+			}
+		}
+	}
+
+	// Add only properties that are common to all tiles.
+	for (List<PLData *>::Element *E = data_list.front(); E; E = E->next()) {
+		if (E->get()->uses == tiles.size()) {
+			p_list->push_back(E->get()->property_info);
+		}
+	}
+}
+
+void TileSetAtlasSourceEditor::TileProxyObject::edit(TileSetAtlasSource *p_tile_set_atlas_source, int p_source_id, Set<TileSelection> p_tiles) {
+	ERR_FAIL_COND(!p_tile_set_atlas_source);
+	ERR_FAIL_COND(p_source_id < 0);
+	ERR_FAIL_COND(p_tiles.is_empty());
+	for (Set<TileSelection>::Element *E = p_tiles.front(); E; E = E->next()) {
+		ERR_FAIL_COND(E->get().tile == TileSetAtlasSource::INVALID_ATLAS_COORDS);
+		ERR_FAIL_COND(E->get().alternative < 0);
+	}
+
+	// Disconnect to changes.
+	for (Set<TileSelection>::Element *E = tiles.front(); E; E = E->next()) {
+		const Vector2i &coords = E->get().tile;
+		const int &alternative = E->get().alternative;
+
+		if (tile_set_atlas_source && tile_set_atlas_source->has_tile(coords) && tile_set_atlas_source->has_alternative_tile(coords, alternative)) {
+			TileData *tile_data = Object::cast_to<TileData>(tile_set_atlas_source->get_tile_data(coords, alternative));
+			if (tile_data->is_connected(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed))) {
+				tile_data->disconnect(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed));
+			}
+		}
+	}
+
+	tile_set_atlas_source = p_tile_set_atlas_source;
+	source_id = p_source_id;
+	tiles = Set<TileSelection>(p_tiles);
+
+	// Connect to changes.
+	for (Set<TileSelection>::Element *E = p_tiles.front(); E; E = E->next()) {
+		const Vector2i &coords = E->get().tile;
+		const int &alternative = E->get().alternative;
+
+		if (tile_set_atlas_source->has_tile(coords) && tile_set_atlas_source->has_alternative_tile(coords, alternative)) {
+			TileData *tile_data = Object::cast_to<TileData>(tile_set_atlas_source->get_tile_data(coords, alternative));
+			if (!tile_data->is_connected(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed))) {
+				tile_data->connect(CoreStringNames::get_singleton()->property_list_changed, callable_mp((Object *)this, &Object::notify_property_list_changed));
+			}
+		}
+	}
+
+	notify_property_list_changed();
+}
+
+void TileSetAtlasSourceEditor::TileProxyObject::_bind_methods() {
+	ADD_SIGNAL(MethodInfo("changed", PropertyInfo(Variant::STRING, "what")));
+}
+
+void TileSetAtlasSourceEditor::_inspector_property_selected(String p_property) {
+	selected_property = p_property;
+	_update_atlas_view();
+}
+
+void TileSetAtlasSourceEditor::_update_tile_id_label() {
+	if (selection.size() == 1) {
+		TileSelection selected = selection.front()->get();
+		tool_tile_id_label->set_text(vformat("%d, %s, %d", tile_set_atlas_source_id, selected.tile, selected.alternative));
+		tool_tile_id_label->set_tooltip(vformat(TTR("Selected tile:\nSource: %d\nAtlas coordinates: %s\nAlternative: %d"), tile_set_atlas_source_id, selected.tile, selected.alternative));
+		tool_tile_id_label->show();
+	} else {
+		tool_tile_id_label->hide();
+	}
+}
+
+void TileSetAtlasSourceEditor::_update_source_inspector() {
+	// Update the proxy object.
+	atlas_source_proxy_object->edit(tile_set, tile_set_atlas_source, tile_set_atlas_source_id);
+
+	// Update the "clear outside texture" button.
+	tool_advanced_menu_buttom->get_popup()->set_item_disabled(0, !tile_set_atlas_source->has_tiles_outside_texture());
+}
+
+void TileSetAtlasSourceEditor::_update_fix_selected_and_hovered_tiles() {
+	// Fix selected.
+	for (Set<TileSelection>::Element *E = selection.front(); E; E = E->next()) {
+		TileSelection selected = E->get();
+		if (!tile_set_atlas_source->has_tile(selected.tile) || !tile_set_atlas_source->has_alternative_tile(selected.tile, selected.alternative)) {
+			selection.erase(E);
+		}
+	}
+
+	// Fix hovered.
+	if (!tile_set_atlas_source->has_tile(hovered_base_tile_coords)) {
+		hovered_base_tile_coords = TileSetAtlasSource::INVALID_ATLAS_COORDS;
+	}
+	Vector2i coords = Vector2i(hovered_alternative_tile_coords.x, hovered_alternative_tile_coords.y);
+	int alternative = hovered_alternative_tile_coords.z;
+	if (!tile_set_atlas_source->has_tile(coords) || !tile_set_atlas_source->has_alternative_tile(coords, alternative)) {
+		hovered_alternative_tile_coords = Vector3i(TileSetAtlasSource::INVALID_ATLAS_COORDS.x, TileSetAtlasSource::INVALID_ATLAS_COORDS.y, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+	}
+}
+
+void TileSetAtlasSourceEditor::_update_tile_inspector() {
+	bool has_atlas_tile_selected = (tools_button_group->get_pressed_button() == tool_select_button) && !selection.is_empty();
+
+	// Update the proxy object.
+	if (has_atlas_tile_selected) {
+		tile_proxy_object->edit(tile_set_atlas_source, tile_set_atlas_source_id, selection);
+	}
+
+	// Update visibility.
+	tile_inspector_label->set_visible(has_atlas_tile_selected);
+	tile_inspector->set_visible(has_atlas_tile_selected);
+}
+
+void TileSetAtlasSourceEditor::_update_atlas_view() {
+	// Update the atlas display.
+	tile_atlas_view->set_atlas_source(*tile_set, tile_set_atlas_source, tile_set_atlas_source_id);
+
+	// Create a bunch of buttons to add alternative tiles.
+	for (int i = 0; i < alternative_tiles_control->get_child_count(); i++) {
+		alternative_tiles_control->get_child(i)->queue_delete();
+	}
+
+	Vector2i pos;
+	Vector2 texture_region_base_size = tile_set_atlas_source->get_texture_region_size();
+	int texture_region_base_size_min = MIN(texture_region_base_size.x, texture_region_base_size.y);
+	for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+		Vector2i tile_id = tile_set_atlas_source->get_tile_id(i);
+		int alternative_count = tile_set_atlas_source->get_alternative_tiles_count(tile_id);
+		if (alternative_count > 1) {
+			// Compute the right extremity of alternative.
+			int y_increment = 0;
+			pos.x = 0;
+			for (int j = 1; j < alternative_count; j++) {
+				int alternative_id = tile_set_atlas_source->get_alternative_tile_id(tile_id, j);
+				Rect2i rect = tile_atlas_view->get_alternative_tile_rect(tile_id, alternative_id);
+				pos.x = MAX(pos.x, rect.get_end().x);
+				y_increment = MAX(y_increment, rect.size.y);
+			}
+
+			// Create and position the button.
+			Button *button = memnew(Button);
+			alternative_tiles_control->add_child(button);
+			button->set_flat(true);
+			button->set_icon(get_theme_icon("Add", "EditorIcons"));
+			button->add_theme_style_override("normal", memnew(StyleBoxEmpty));
+			button->add_theme_style_override("hover", memnew(StyleBoxEmpty));
+			button->add_theme_style_override("focus", memnew(StyleBoxEmpty));
+			button->add_theme_style_override("pressed", memnew(StyleBoxEmpty));
+			button->connect("pressed", callable_mp(tile_set_atlas_source, &TileSetAtlasSource::create_alternative_tile), varray(tile_id, -1));
+			button->set_rect(Rect2(Vector2(pos.x, pos.y + (y_increment - texture_region_base_size.y) / 2.0), Vector2(texture_region_base_size_min, texture_region_base_size_min)));
+			button->set_expand_icon(true);
+
+			pos.y += y_increment;
+		}
+	}
+	tile_atlas_view->set_padding(Side::SIDE_RIGHT, texture_region_base_size_min);
+
+	// Redraw everything.
+	tile_atlas_control->update();
+	tile_atlas_control_unscaled->update();
+	alternative_tiles_control->update();
+	alternative_tiles_control_unscaled->update();
+	tile_atlas_view->update();
+
+	// Synchronize atlas view.
+	TilesEditor::get_singleton()->synchronize_atlas_view(tile_atlas_view);
+}
+
+void TileSetAtlasSourceEditor::_update_toolbar() {
+	// Hide all settings.
+	for (int i = 0; i < tool_settings->get_child_count(); i++) {
+		Object::cast_to<CanvasItem>(tool_settings->get_child(i))->hide();
+	}
+
+	// SHow only the correct settings.
+	if (tools_button_group->get_pressed_button() == tool_select_button) {
+	} else if (tools_button_group->get_pressed_button() == tool_add_remove_button) {
+		tool_settings_vsep->show();
+		tools_settings_erase_button->show();
+	} else if (tools_button_group->get_pressed_button() == tool_add_remove_rect_button) {
+		tool_settings_vsep->show();
+		tools_settings_erase_button->show();
+	}
+}
+
+void TileSetAtlasSourceEditor::_tile_atlas_control_mouse_exited() {
+	hovered_base_tile_coords = TileSetAtlasSource::INVALID_ATLAS_COORDS;
+	tile_atlas_control->update();
+	tile_atlas_control_unscaled->update();
+	tile_atlas_view->update();
+}
+
+void TileSetAtlasSourceEditor::_tile_atlas_view_transform_changed() {
+	tile_atlas_control->update();
+	tile_atlas_control_unscaled->update();
+}
+
+void TileSetAtlasSourceEditor::_tile_atlas_control_gui_input(const Ref<InputEvent> &p_event) {
+	// Update the hovered coords.
+	hovered_base_tile_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+
+	// Handle the event.
+	Ref<InputEventMouseMotion> mm = p_event;
+	if (mm.is_valid()) {
+		Vector2i start_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+		Vector2i last_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_last_mouse_pos);
+		Vector2i new_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+
+		Vector2i grid_size = tile_set_atlas_source->get_atlas_grid_size();
+
+		if (drag_type == DRAG_TYPE_NONE) {
+			if (selection.size() == 1) {
+				// Change the cursor depending on the hovered thing.
+				TileSelection selected = selection.front()->get();
+				if (selected.tile != TileSetAtlasSource::INVALID_ATLAS_COORDS && selected.alternative == 0) {
+					Vector2 mouse_local_pos = tile_atlas_control->get_local_mouse_position();
+					Vector2i size_in_atlas = tile_set_atlas_source->get_tile_size_in_atlas(selected.tile);
+					Rect2 region = tile_set_atlas_source->get_tile_texture_region(selected.tile);
+					Size2 zoomed_size = resize_handle->get_size() / tile_atlas_view->get_zoom();
+					Rect2 rect = region.grow_individual(zoomed_size.x, zoomed_size.y, 0, 0);
+					const Vector2i coords[] = { Vector2i(0, 0), Vector2i(1, 0), Vector2i(1, 1), Vector2i(0, 1) };
+					const Vector2i directions[] = { Vector2i(0, -1), Vector2i(1, 0), Vector2i(0, 1), Vector2i(-1, 0) };
+					CursorShape cursor_shape = CURSOR_ARROW;
+					bool can_grow[4];
+					for (int i = 0; i < 4; i++) {
+						can_grow[i] = tile_set_atlas_source->can_move_tile_in_atlas(selected.tile, selected.tile + directions[i]);
+						can_grow[i] |= (i % 2 == 0) ? size_in_atlas.y > 1 : size_in_atlas.x > 1;
+					}
+					for (int i = 0; i < 4; i++) {
+						Vector2 pos = rect.position + Vector2(rect.size.x, rect.size.y) * coords[i];
+						if (can_grow[i] && can_grow[(i + 3) % 4] && Rect2(pos, zoomed_size).has_point(mouse_local_pos)) {
+							cursor_shape = (i % 2) ? CURSOR_BDIAGSIZE : CURSOR_FDIAGSIZE;
+						}
+						Vector2 next_pos = rect.position + Vector2(rect.size.x, rect.size.y) * coords[(i + 1) % 4];
+						if (can_grow[i] && Rect2((pos + next_pos) / 2.0, zoomed_size).has_point(mouse_local_pos)) {
+							cursor_shape = (i % 2) ? CURSOR_HSIZE : CURSOR_VSIZE;
+						}
+					}
+					tile_atlas_control->set_default_cursor_shape(cursor_shape);
+				}
+			}
+		} else if (drag_type == DRAG_TYPE_CREATE_BIG_TILE) {
+			// Create big tile.
+			new_base_tiles_coords = new_base_tiles_coords.max(Vector2i(0, 0)).min(grid_size - Vector2i(1, 1));
+
+			Rect2i new_rect = Rect2i(start_base_tiles_coords, new_base_tiles_coords - start_base_tiles_coords).abs();
+			new_rect.size += Vector2i(1, 1);
+			// Check if the new tile can fit in the new rect.
+			if (tile_set_atlas_source->can_move_tile_in_atlas(drag_current_tile, new_rect.position, new_rect.size)) {
+				// Move and resize the tile.
+				tile_set_atlas_source->move_tile_in_atlas(drag_current_tile, new_rect.position, new_rect.size);
+				drag_current_tile = new_rect.position;
+			}
+		} else if (drag_type == DRAG_TYPE_CREATE_TILES) {
+			// Create tiles.
+			last_base_tiles_coords = last_base_tiles_coords.max(Vector2i(0, 0)).min(grid_size - Vector2i(1, 1));
+			new_base_tiles_coords = new_base_tiles_coords.max(Vector2i(0, 0)).min(grid_size - Vector2i(1, 1));
+
+			Vector<Point2i> line = Geometry2D::bresenham_line(last_base_tiles_coords, new_base_tiles_coords);
+			for (int i = 0; i < line.size(); i++) {
+				if (tile_set_atlas_source->get_tile_at_coords(line[i]) == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					tile_set_atlas_source->create_tile(line[i]);
+					drag_modified_tiles.insert(line[i]);
+				}
+			}
+
+			drag_last_mouse_pos = tile_atlas_control->get_local_mouse_position();
+
+		} else if (drag_type == DRAG_TYPE_REMOVE_TILES) {
+			// Remove tiles.
+			last_base_tiles_coords = last_base_tiles_coords.max(Vector2i(0, 0)).min(grid_size - Vector2i(1, 1));
+			new_base_tiles_coords = new_base_tiles_coords.max(Vector2i(0, 0)).min(grid_size - Vector2i(1, 1));
+
+			Vector<Point2i> line = Geometry2D::bresenham_line(last_base_tiles_coords, new_base_tiles_coords);
+			for (int i = 0; i < line.size(); i++) {
+				Vector2i base_tile_coords = tile_set_atlas_source->get_tile_at_coords(line[i]);
+				if (base_tile_coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					drag_modified_tiles.insert(base_tile_coords);
+				}
+			}
+
+			drag_last_mouse_pos = tile_atlas_control->get_local_mouse_position();
+		} else if (drag_type == DRAG_TYPE_MOVE_TILE) {
+			// Move tile.
+			Vector2 mouse_offset = (Vector2(tile_set_atlas_source->get_tile_size_in_atlas(drag_current_tile)) / 2.0 - Vector2(0.5, 0.5)) * tile_set->get_tile_size();
+			Vector2i coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position() - mouse_offset);
+			coords = coords.max(Vector2i(0, 0)).min(grid_size - Vector2i(1, 1));
+			if (drag_current_tile != coords && tile_set_atlas_source->can_move_tile_in_atlas(drag_current_tile, coords)) {
+				tile_set_atlas_source->move_tile_in_atlas(drag_current_tile, coords);
+				selection.clear();
+				selection.insert({ coords, 0 });
+				drag_current_tile = coords;
+
+				// Update only what's needed.
+				tile_set_atlas_source_changed_needs_update = false;
+				_update_tile_inspector();
+				_update_atlas_view();
+				_update_tile_id_label();
+			}
+		} else if (drag_type >= DRAG_TYPE_RESIZE_TOP_LEFT && drag_type <= DRAG_TYPE_RESIZE_LEFT) {
+			// Resizing a tile.
+			new_base_tiles_coords = new_base_tiles_coords.max(Vector2i(-1, -1)).min(grid_size);
+
+			Rect2i old_rect = Rect2i(drag_current_tile, tile_set_atlas_source->get_tile_size_in_atlas(drag_current_tile));
+			Rect2i new_rect = old_rect;
+
+			if (drag_type == DRAG_TYPE_RESIZE_LEFT || drag_type == DRAG_TYPE_RESIZE_TOP_LEFT || drag_type == DRAG_TYPE_RESIZE_BOTTOM_LEFT) {
+				new_rect.position.x = MIN(new_base_tiles_coords.x + 1, old_rect.get_end().x - 1);
+				new_rect.size.x = old_rect.get_end().x - new_rect.position.x;
+			}
+			if (drag_type == DRAG_TYPE_RESIZE_TOP || drag_type == DRAG_TYPE_RESIZE_TOP_LEFT || drag_type == DRAG_TYPE_RESIZE_TOP_RIGHT) {
+				new_rect.position.y = MIN(new_base_tiles_coords.y + 1, old_rect.get_end().y - 1);
+				new_rect.size.y = old_rect.get_end().y - new_rect.position.y;
+			}
+
+			if (drag_type == DRAG_TYPE_RESIZE_RIGHT || drag_type == DRAG_TYPE_RESIZE_TOP_RIGHT || drag_type == DRAG_TYPE_RESIZE_BOTTOM_RIGHT) {
+				new_rect.set_end(Vector2i(MAX(new_base_tiles_coords.x, old_rect.position.x + 1), new_rect.get_end().y));
+			}
+			if (drag_type == DRAG_TYPE_RESIZE_BOTTOM || drag_type == DRAG_TYPE_RESIZE_BOTTOM_LEFT || drag_type == DRAG_TYPE_RESIZE_BOTTOM_RIGHT) {
+				new_rect.set_end(Vector2i(new_rect.get_end().x, MAX(new_base_tiles_coords.y, old_rect.position.y + 1)));
+			}
+
+			if (tile_set_atlas_source->can_move_tile_in_atlas(drag_current_tile, new_rect.position, new_rect.size)) {
+				tile_set_atlas_source->move_tile_in_atlas(drag_current_tile, new_rect.position, new_rect.size);
+				selection.clear();
+				selection.insert({ new_rect.position, 0 });
+				drag_current_tile = new_rect.position;
+
+				// Update only what's needed.
+				tile_set_atlas_source_changed_needs_update = false;
+				_update_tile_inspector();
+				_update_atlas_view();
+				_update_tile_id_label();
+			}
+		}
+
+		// Redraw for the hovered tile.
+		tile_atlas_control->update();
+		tile_atlas_control_unscaled->update();
+		alternative_tiles_control->update();
+		alternative_tiles_control_unscaled->update();
+		tile_atlas_view->update();
+		return;
+	}
+
+	Ref<InputEventMouseButton> mb = p_event;
+	if (mb.is_valid()) {
+		Vector2 mouse_local_pos = tile_atlas_control->get_local_mouse_position();
+		if (mb->get_button_index() == MOUSE_BUTTON_LEFT) {
+			if (mb->is_pressed()) {
+				// Left click pressed.
+				if (tools_button_group->get_pressed_button() == tool_add_remove_button) {
+					if (tools_settings_erase_button->is_pressed()) {
+						// Remove tiles.
+
+						// Setup the dragging info.
+						drag_type = DRAG_TYPE_REMOVE_TILES;
+						drag_start_mouse_pos = mouse_local_pos;
+						drag_last_mouse_pos = drag_start_mouse_pos;
+
+						// Remove a first tile.
+						Vector2i coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+						if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+							coords = tile_set_atlas_source->get_tile_at_coords(coords);
+						}
+						if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+							drag_modified_tiles.insert(coords);
+						}
+					} else {
+						if (mb->get_shift()) {
+							// Create a big tile.
+							Vector2i coords = tile_atlas_view->get_atlas_tile_coords_at_pos(mouse_local_pos);
+							if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS && tile_set_atlas_source->get_tile_at_coords(coords) == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+								// Setup the dragging info, only if we start on an empty tile.
+								drag_type = DRAG_TYPE_CREATE_BIG_TILE;
+								drag_start_mouse_pos = mouse_local_pos;
+								drag_last_mouse_pos = drag_start_mouse_pos;
+								drag_current_tile = coords;
+
+								// Create a tile.
+								tile_set_atlas_source->create_tile(coords);
+							}
+						} else {
+							// Create tiles.
+
+							// Setup the dragging info.
+							drag_type = DRAG_TYPE_CREATE_TILES;
+							drag_start_mouse_pos = mouse_local_pos;
+							drag_last_mouse_pos = drag_start_mouse_pos;
+
+							// Create a first tile if needed.
+							Vector2i coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+							if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS && tile_set_atlas_source->get_tile_at_coords(coords) == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+								tile_set_atlas_source->create_tile(coords);
+								drag_modified_tiles.insert(coords);
+							}
+						}
+					}
+				} else if (tools_button_group->get_pressed_button() == tool_add_remove_rect_button) {
+					if (tools_settings_erase_button->is_pressed()) {
+						// Remove tiles using rect.
+
+						// Setup the dragging info.
+						drag_type = DRAG_TYPE_REMOVE_TILES_USING_RECT;
+						drag_start_mouse_pos = mouse_local_pos;
+						drag_last_mouse_pos = drag_start_mouse_pos;
+					} else {
+						if (mb->get_shift()) {
+							// Create a big tile.
+							Vector2i coords = tile_atlas_view->get_atlas_tile_coords_at_pos(mouse_local_pos);
+							if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS && tile_set_atlas_source->get_tile_at_coords(coords) == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+								// Setup the dragging info, only if we start on an empty tile.
+								drag_type = DRAG_TYPE_CREATE_BIG_TILE;
+								drag_start_mouse_pos = mouse_local_pos;
+								drag_last_mouse_pos = drag_start_mouse_pos;
+								drag_current_tile = coords;
+
+								// Create a tile.
+								tile_set_atlas_source->create_tile(coords);
+							}
+						} else {
+							// Create tiles using rect.
+							drag_type = DRAG_TYPE_CREATE_TILES_USING_RECT;
+							drag_start_mouse_pos = mouse_local_pos;
+							drag_last_mouse_pos = drag_start_mouse_pos;
+						}
+					}
+				} else if (tools_button_group->get_pressed_button() == tool_select_button) {
+					// Dragging a handle.
+					drag_type = DRAG_TYPE_NONE;
+					if (selection.size() == 1) {
+						TileSelection selected = selection.front()->get();
+						if (selected.tile != TileSetAtlasSource::INVALID_ATLAS_COORDS && selected.alternative == 0) {
+							Vector2i size_in_atlas = tile_set_atlas_source->get_tile_size_in_atlas(selected.tile);
+							Rect2 region = tile_set_atlas_source->get_tile_texture_region(selected.tile);
+							Size2 zoomed_size = resize_handle->get_size() / tile_atlas_view->get_zoom();
+							Rect2 rect = region.grow_individual(zoomed_size.x, zoomed_size.y, 0, 0);
+							const Vector2i coords[] = { Vector2i(0, 0), Vector2i(1, 0), Vector2i(1, 1), Vector2i(0, 1) };
+							const Vector2i directions[] = { Vector2i(0, -1), Vector2i(1, 0), Vector2i(0, 1), Vector2i(-1, 0) };
+							CursorShape cursor_shape = CURSOR_ARROW;
+							bool can_grow[4];
+							for (int i = 0; i < 4; i++) {
+								can_grow[i] = tile_set_atlas_source->can_move_tile_in_atlas(selected.tile, selected.tile + directions[i]);
+								can_grow[i] |= (i % 2 == 0) ? size_in_atlas.y > 1 : size_in_atlas.x > 1;
+							}
+							for (int i = 0; i < 4; i++) {
+								Vector2 pos = rect.position + Vector2(rect.size.x, rect.size.y) * coords[i];
+								if (can_grow[i] && can_grow[(i + 3) % 4] && Rect2(pos, zoomed_size).has_point(mouse_local_pos)) {
+									drag_type = (DragType)((int)DRAG_TYPE_RESIZE_TOP_LEFT + i * 2);
+									drag_start_mouse_pos = mouse_local_pos;
+									drag_last_mouse_pos = drag_start_mouse_pos;
+									drag_current_tile = selected.tile;
+									drag_start_tile_shape = Rect2i(selected.tile, tile_set_atlas_source->get_tile_size_in_atlas(selected.tile));
+									cursor_shape = (i % 2) ? CURSOR_BDIAGSIZE : CURSOR_FDIAGSIZE;
+								}
+								Vector2 next_pos = rect.position + Vector2(rect.size.x, rect.size.y) * coords[(i + 1) % 4];
+								if (can_grow[i] && Rect2((pos + next_pos) / 2.0, zoomed_size).has_point(mouse_local_pos)) {
+									drag_type = (DragType)((int)DRAG_TYPE_RESIZE_TOP + i * 2);
+									drag_start_mouse_pos = mouse_local_pos;
+									drag_last_mouse_pos = drag_start_mouse_pos;
+									drag_current_tile = selected.tile;
+									drag_start_tile_shape = Rect2i(selected.tile, tile_set_atlas_source->get_tile_size_in_atlas(selected.tile));
+									cursor_shape = (i % 2) ? CURSOR_HSIZE : CURSOR_VSIZE;
+								}
+							}
+							tile_atlas_control->set_default_cursor_shape(cursor_shape);
+						}
+					}
+
+					// Selecting then dragging a tile.
+					if (drag_type == DRAG_TYPE_NONE) {
+						TileSelection selected = { TileSetAtlasSource::INVALID_ATLAS_COORDS, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE };
+						Vector2i coords = tile_atlas_view->get_atlas_tile_coords_at_pos(mouse_local_pos);
+						if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+							coords = tile_set_atlas_source->get_tile_at_coords(coords);
+							if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+								selected = { coords, 0 };
+							}
+						}
+
+						bool shift = mb->get_shift();
+						if (!shift && selection.size() == 1 && selected.tile != TileSetAtlasSource::INVALID_ATLAS_COORDS && selection.has(selected)) {
+							// Start move dragging.
+							drag_type = DRAG_TYPE_MOVE_TILE;
+							drag_start_mouse_pos = mouse_local_pos;
+							drag_last_mouse_pos = drag_start_mouse_pos;
+							drag_current_tile = selected.tile;
+							drag_start_tile_shape = Rect2i(selected.tile, tile_set_atlas_source->get_tile_size_in_atlas(selected.tile));
+							tile_atlas_control->set_default_cursor_shape(CURSOR_MOVE);
+						} else {
+							// Start selection dragging.
+							drag_type = DRAG_TYPE_RECT_SELECT;
+							drag_start_mouse_pos = mouse_local_pos;
+							drag_last_mouse_pos = drag_start_mouse_pos;
+						}
+					}
+				}
+			} else {
+				// Left click released.
+				_end_dragging();
+			}
+			tile_atlas_control->update();
+			tile_atlas_control_unscaled->update();
+			alternative_tiles_control->update();
+			alternative_tiles_control_unscaled->update();
+			tile_atlas_view->update();
+			return;
+		} else if (mb->get_button_index() == MOUSE_BUTTON_RIGHT) {
+			if (mb->is_pressed()) {
+				// Right click pressed.
+
+				TileSelection selected = { tile_atlas_view->get_atlas_tile_coords_at_pos(mouse_local_pos), 0 };
+				if (selected.tile != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					selected.tile = tile_set_atlas_source->get_tile_at_coords(selected.tile);
+				}
+
+				// Set the selection if needed.
+				if (selection.size() <= 1) {
+					if (selected.tile != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+						undo_redo->create_action(TTR("Select tiles"));
+						undo_redo->add_undo_method(this, "_set_selection_from_array", _get_selection_as_array());
+						selection.clear();
+						selection.insert(selected);
+						undo_redo->add_do_method(this, "_set_selection_from_array", _get_selection_as_array());
+						undo_redo->commit_action(false);
+						_update_tile_inspector();
+						_update_tile_id_label();
+					}
+				}
+
+				// Pops up the correct menu, depending on whether we have a tile or not.
+				if (selected.tile != TileSetAtlasSource::INVALID_ATLAS_COORDS && selection.has(selected)) {
+					// We have a tile.
+					menu_option_coords = selected.tile;
+					menu_option_alternative = 0;
+					base_tile_popup_menu->popup(Rect2i(get_global_mouse_position(), Size2i()));
+				} else if (hovered_base_tile_coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					// We don't have a tile, but can create one.
+					menu_option_coords = hovered_base_tile_coords;
+					menu_option_alternative = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+					empty_base_tile_popup_menu->popup(Rect2i(get_global_mouse_position(), Size2i()));
+				}
+			} else {
+				// Right click released.
+				_end_dragging();
+			}
+			tile_atlas_control->update();
+			tile_atlas_control_unscaled->update();
+			alternative_tiles_control->update();
+			alternative_tiles_control_unscaled->update();
+			tile_atlas_view->update();
+			return;
+		}
+	}
+}
+
+void TileSetAtlasSourceEditor::_end_dragging() {
+	switch (drag_type) {
+		case DRAG_TYPE_CREATE_TILES:
+			undo_redo->create_action(TTR("Create tiles"));
+			for (Set<Vector2i>::Element *E = drag_modified_tiles.front(); E; E = E->next()) {
+				undo_redo->add_do_method(tile_set_atlas_source, "create_tile", E->get());
+				undo_redo->add_undo_method(tile_set_atlas_source, "remove_tile", E->get());
+			}
+			undo_redo->commit_action(false);
+			break;
+		case DRAG_TYPE_CREATE_BIG_TILE:
+			undo_redo->create_action(TTR("Create a tile"));
+			undo_redo->add_do_method(tile_set_atlas_source, "create_tile", drag_current_tile, tile_set_atlas_source->get_tile_size_in_atlas(drag_current_tile));
+			undo_redo->add_undo_method(tile_set_atlas_source, "remove_tile", drag_current_tile);
+			undo_redo->commit_action(false);
+			break;
+		case DRAG_TYPE_REMOVE_TILES: {
+			List<PropertyInfo> list;
+			tile_set_atlas_source->get_property_list(&list);
+			Map<Vector2i, List<const PropertyInfo *>> per_tile = _group_properties_per_tiles(list, tile_set_atlas_source);
+			undo_redo->create_action(TTR("Remove tiles"));
+			for (Set<Vector2i>::Element *E = drag_modified_tiles.front(); E; E = E->next()) {
+				Vector2i coords = E->get();
+				undo_redo->add_do_method(tile_set_atlas_source, "remove_tile", coords);
+				undo_redo->add_undo_method(tile_set_atlas_source, "create_tile", coords);
+				if (per_tile.has(coords)) {
+					for (List<const PropertyInfo *>::Element *E_property = per_tile[coords].front(); E_property; E_property = E_property->next()) {
+						String property = E_property->get()->name;
+						Variant value = tile_set_atlas_source->get(property);
+						if (value.get_type() != Variant::NIL) {
+							undo_redo->add_undo_method(tile_set_atlas_source, "set", E_property->get()->name, value);
+						}
+					}
+				}
+			}
+			undo_redo->commit_action();
+		} break;
+		case DRAG_TYPE_CREATE_TILES_USING_RECT: {
+			Vector2i start_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+			Vector2i new_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+			Rect2i area = Rect2i(start_base_tiles_coords, new_base_tiles_coords - start_base_tiles_coords).abs();
+			area.set_end((area.get_end() + Vector2i(1, 1)).min(tile_set_atlas_source->get_atlas_grid_size()));
+			undo_redo->create_action(TTR("Create tiles"));
+			for (int x = area.get_position().x; x < area.get_end().x; x++) {
+				for (int y = area.get_position().y; y < area.get_end().y; y++) {
+					Vector2i coords = Vector2i(x, y);
+					if (tile_set_atlas_source->get_tile_at_coords(coords) == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+						undo_redo->add_do_method(tile_set_atlas_source, "create_tile", coords);
+						undo_redo->add_undo_method(tile_set_atlas_source, "remove_tile", coords);
+					}
+				}
+			}
+			undo_redo->commit_action();
+		} break;
+		case DRAG_TYPE_REMOVE_TILES_USING_RECT: {
+			Vector2i start_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+			Vector2i new_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+			Rect2i area = Rect2i(start_base_tiles_coords, new_base_tiles_coords - start_base_tiles_coords).abs();
+			area.set_end((area.get_end() + Vector2i(1, 1)).min(tile_set_atlas_source->get_atlas_grid_size()));
+			List<PropertyInfo> list;
+			tile_set_atlas_source->get_property_list(&list);
+			Map<Vector2i, List<const PropertyInfo *>> per_tile = _group_properties_per_tiles(list, tile_set_atlas_source);
+
+			Set<Vector2i> to_delete;
+			for (int x = area.get_position().x; x < area.get_end().x; x++) {
+				for (int y = area.get_position().y; y < area.get_end().y; y++) {
+					Vector2i coords = tile_set_atlas_source->get_tile_at_coords(Vector2i(x, y));
+					if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+						to_delete.insert(coords);
+					}
+				}
+			}
+
+			undo_redo->create_action(TTR("Remove tiles"));
+			undo_redo->add_do_method(this, "_set_selection_from_array", Array());
+			for (Set<Vector2i>::Element *E = to_delete.front(); E; E = E->next()) {
+				Vector2i coords = E->get();
+				undo_redo->add_do_method(tile_set_atlas_source, "remove_tile", coords);
+				undo_redo->add_undo_method(tile_set_atlas_source, "create_tile", coords);
+				if (per_tile.has(coords)) {
+					for (List<const PropertyInfo *>::Element *E_property = per_tile[coords].front(); E_property; E_property = E_property->next()) {
+						String property = E_property->get()->name;
+						Variant value = tile_set_atlas_source->get(property);
+						if (value.get_type() != Variant::NIL) {
+							undo_redo->add_undo_method(tile_set_atlas_source, "set", E_property->get()->name, value);
+						}
+					}
+				}
+			}
+			undo_redo->add_undo_method(this, "_set_selection_from_array", _get_selection_as_array());
+			undo_redo->commit_action();
+		} break;
+		case DRAG_TYPE_MOVE_TILE:
+			if (drag_current_tile != drag_start_tile_shape.position) {
+				undo_redo->create_action(TTR("Move a tile"));
+				undo_redo->add_do_method(tile_set_atlas_source, "move_tile_in_atlas", drag_start_tile_shape.position, drag_current_tile, tile_set_atlas_source->get_tile_size_in_atlas(drag_current_tile));
+				undo_redo->add_do_method(this, "_set_selection_from_array", _get_selection_as_array());
+				undo_redo->add_undo_method(tile_set_atlas_source, "move_tile_in_atlas", drag_current_tile, drag_start_tile_shape.position, drag_start_tile_shape.size);
+				Array array;
+				array.push_back(drag_start_tile_shape.position);
+				array.push_back(0);
+				undo_redo->add_undo_method(this, "_set_selection_from_array", array);
+				undo_redo->commit_action(false);
+			}
+			break;
+		case DRAG_TYPE_RECT_SELECT: {
+			Vector2i start_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+			Vector2i new_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+			ERR_FAIL_COND(start_base_tiles_coords == TileSetAtlasSource::INVALID_ATLAS_COORDS);
+			ERR_FAIL_COND(new_base_tiles_coords == TileSetAtlasSource::INVALID_ATLAS_COORDS);
+
+			Rect2i region = Rect2i(start_base_tiles_coords, new_base_tiles_coords - start_base_tiles_coords).abs();
+			region.size += Vector2i(1, 1);
+
+			undo_redo->create_action(TTR("Select tiles"));
+			undo_redo->add_undo_method(this, "_set_selection_from_array", _get_selection_as_array());
+
+			// Determine if we clear, then add or remove to the selection.
+			bool add_to_selection = true;
+			if (Input::get_singleton()->is_key_pressed(KEY_SHIFT)) {
+				Vector2i coords = tile_set_atlas_source->get_tile_at_coords(start_base_tiles_coords);
+				if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					if (selection.has({ coords, 0 })) {
+						add_to_selection = false;
+					}
+				}
+			} else {
+				selection.clear();
+			}
+
+			// Modify the selection.
+			for (int x = region.position.x; x < region.get_end().x; x++) {
+				for (int y = region.position.y; y < region.get_end().y; y++) {
+					Vector2i coords = Vector2i(x, y);
+					coords = tile_set_atlas_source->get_tile_at_coords(coords);
+					if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+						if (add_to_selection && !selection.has({ coords, 0 })) {
+							selection.insert({ coords, 0 });
+						} else if (!add_to_selection && selection.has({ coords, 0 })) {
+							selection.erase({ coords, 0 });
+						}
+					}
+				}
+			}
+			_update_tile_inspector();
+			_update_tile_id_label();
+			undo_redo->add_do_method(this, "_set_selection_from_array", _get_selection_as_array());
+			undo_redo->commit_action(false);
+			break;
+		}
+		case DRAG_TYPE_RESIZE_TOP_LEFT:
+		case DRAG_TYPE_RESIZE_TOP:
+		case DRAG_TYPE_RESIZE_TOP_RIGHT:
+		case DRAG_TYPE_RESIZE_RIGHT:
+		case DRAG_TYPE_RESIZE_BOTTOM_RIGHT:
+		case DRAG_TYPE_RESIZE_BOTTOM:
+		case DRAG_TYPE_RESIZE_BOTTOM_LEFT:
+		case DRAG_TYPE_RESIZE_LEFT:
+			if (drag_start_tile_shape != Rect2i(drag_current_tile, tile_set_atlas_source->get_tile_size_in_atlas(drag_current_tile))) {
+				undo_redo->create_action(TTR("Resize a tile"));
+				undo_redo->add_do_method(tile_set_atlas_source, "move_tile_in_atlas", drag_start_tile_shape.position, drag_current_tile, tile_set_atlas_source->get_tile_size_in_atlas(drag_current_tile));
+				undo_redo->add_do_method(this, "_set_selection_from_array", _get_selection_as_array());
+				undo_redo->add_undo_method(tile_set_atlas_source, "move_tile_in_atlas", drag_current_tile, drag_start_tile_shape.position, drag_start_tile_shape.size);
+				Array array;
+				array.push_back(drag_start_tile_shape.position);
+				array.push_back(0);
+				undo_redo->add_undo_method(this, "_set_selection_from_array", array);
+				undo_redo->commit_action(false);
+			}
+			break;
+		default:
+			break;
+	}
+
+	drag_modified_tiles.clear();
+	drag_type = DRAG_TYPE_NONE;
+	tile_atlas_control->set_default_cursor_shape(CURSOR_ARROW);
+}
+
+Map<Vector2i, List<const PropertyInfo *>> TileSetAtlasSourceEditor::_group_properties_per_tiles(const List<PropertyInfo> &r_list, const TileSetAtlasSource *p_atlas) {
+	// Group properties per tile.
+	Map<Vector2i, List<const PropertyInfo *>> per_tile;
+	for (const List<PropertyInfo>::Element *E_property = r_list.front(); E_property; E_property = E_property->next()) {
+		Vector<String> components = String(E_property->get().name).split("/", true, 1);
+		if (components.size() >= 1) {
+			Vector<String> coord_arr = components[0].split(":");
+			if (coord_arr.size() == 2 && coord_arr[0].is_valid_integer() && coord_arr[1].is_valid_integer()) {
+				Vector2i coords = Vector2i(coord_arr[0].to_int(), coord_arr[1].to_int());
+				per_tile[coords].push_back(&(E_property->get()));
+			}
+		}
+	}
+	return per_tile;
+}
+
+void TileSetAtlasSourceEditor::_menu_option(int p_option) {
+	switch (p_option) {
+		case TILE_DELETE: {
+			List<PropertyInfo> list;
+			tile_set_atlas_source->get_property_list(&list);
+			Map<Vector2i, List<const PropertyInfo *>> per_tile = _group_properties_per_tiles(list, tile_set_atlas_source);
+			undo_redo->create_action(TTR("Remove tile"));
+
+			// Remove tiles
+			Set<Vector2i> removed;
+			for (Set<TileSelection>::Element *E = selection.front(); E; E = E->next()) {
+				TileSelection selected = E->get();
+				if (selected.alternative == 0) {
+					// Remove a tile.
+					undo_redo->add_do_method(tile_set_atlas_source, "remove_tile", selected.tile);
+					undo_redo->add_undo_method(tile_set_atlas_source, "create_tile", selected.tile);
+					removed.insert(selected.tile);
+					if (per_tile.has(selected.tile)) {
+						for (List<const PropertyInfo *>::Element *E_property = per_tile[selected.tile].front(); E_property; E_property = E_property->next()) {
+							String property = E_property->get()->name;
+							Variant value = tile_set_atlas_source->get(property);
+							if (value.get_type() != Variant::NIL) {
+								undo_redo->add_undo_method(tile_set_atlas_source, "set", E_property->get()->name, value);
+							}
+						}
+					}
+				}
+			}
+
+			// Remove alternatives
+			for (Set<TileSelection>::Element *E = selection.front(); E; E = E->next()) {
+				TileSelection selected = E->get();
+				if (selected.alternative > 0 && !removed.has(selected.tile)) {
+					// Remove an alternative tile.
+					undo_redo->add_do_method(tile_set_atlas_source, "remove_alternative_tile", selected.tile, selected.alternative);
+					undo_redo->add_undo_method(tile_set_atlas_source, "create_alternative_tile", selected.tile, selected.alternative);
+					if (per_tile.has(selected.tile)) {
+						for (List<const PropertyInfo *>::Element *E_property = per_tile[selected.tile].front(); E_property; E_property = E_property->next()) {
+							Vector<String> components = E_property->get()->name.split("/", true, 2);
+							if (components.size() >= 2 && components[1].is_valid_integer() && components[1].to_int() == selected.alternative) {
+								String property = E_property->get()->name;
+								Variant value = tile_set_atlas_source->get(property);
+								if (value.get_type() != Variant::NIL) {
+									undo_redo->add_undo_method(tile_set_atlas_source, "set", E_property->get()->name, value);
+								}
+							}
+						}
+					}
+				}
+			}
+			undo_redo->commit_action();
+			_update_fix_selected_and_hovered_tiles();
+			_update_tile_id_label();
+		} break;
+		case TILE_CREATE: {
+			undo_redo->create_action(TTR("Create a tile"));
+			undo_redo->add_do_method(tile_set_atlas_source, "create_tile", menu_option_coords);
+			Array array;
+			array.push_back(menu_option_coords);
+			array.push_back(0);
+			undo_redo->add_do_method(this, "_set_selection_from_array", array);
+			undo_redo->add_undo_method(tile_set_atlas_source, "remove_tile", menu_option_coords);
+			undo_redo->add_undo_method(this, "_set_selection_from_array", _get_selection_as_array());
+			undo_redo->commit_action();
+			_update_tile_id_label();
+		} break;
+		case TILE_CREATE_ALTERNATIVE: {
+			undo_redo->create_action(TTR("Create tile alternatives"));
+			Array array;
+			for (Set<TileSelection>::Element *E = selection.front(); E; E = E->next()) {
+				if (E->get().alternative == 0) {
+					int next_id = tile_set_atlas_source->get_next_alternative_tile_id(E->get().tile);
+					undo_redo->add_do_method(tile_set_atlas_source, "create_alternative_tile", E->get().tile, next_id);
+					array.push_back(E->get().tile);
+					array.push_back(next_id);
+					undo_redo->add_undo_method(tile_set_atlas_source, "remove_alternative_tile", E->get().tile, next_id);
+				}
+			}
+			undo_redo->add_do_method(this, "_set_selection_from_array", array);
+			undo_redo->add_undo_method(this, "_set_selection_from_array", _get_selection_as_array());
+			undo_redo->commit_action();
+			_update_tile_id_label();
+		} break;
+		case ADVANCED_CLEANUP_TILES_OUTSIDE_TEXTURE: {
+			tile_set_atlas_source->clear_tiles_outside_texture();
+		} break;
+		case ADVANCED_AUTO_CREATE_TILES: {
+			_auto_create_tiles();
+		} break;
+		case ADVANCED_AUTO_REMOVE_TILES: {
+			_auto_remove_tiles();
+		} break;
+	}
+}
+
+void TileSetAtlasSourceEditor::_unhandled_key_input(const Ref<InputEvent> &p_event) {
+	// Check for shortcuts.
+	if (ED_IS_SHORTCUT("tiles_editor/delete_tile", p_event)) {
+		if (tools_button_group->get_pressed_button() == tool_select_button && !selection.is_empty()) {
+			_menu_option(TILE_DELETE);
+			accept_event();
+		}
+	}
+}
+
+void TileSetAtlasSourceEditor::_set_selection_from_array(Array p_selection) {
+	ERR_FAIL_COND((p_selection.size() % 2) != 0);
+	selection.clear();
+	for (int i = 0; i < p_selection.size() / 2; i++) {
+		TileSelection selected = { p_selection[i * 2], p_selection[i * 2 + 1] };
+		if (tile_set_atlas_source->has_tile(selected.tile) && tile_set_atlas_source->has_alternative_tile(selected.tile, selected.alternative)) {
+			selection.insert(selected);
+		}
+	}
+	_update_tile_inspector();
+	_update_tile_id_label();
+	_update_atlas_view();
+}
+
+Array TileSetAtlasSourceEditor::_get_selection_as_array() {
+	Array output;
+	for (Set<TileSelection>::Element *E = selection.front(); E; E = E->next()) {
+		output.push_back(E->get().tile);
+		output.push_back(E->get().alternative);
+	}
+	return output;
+}
+
+void TileSetAtlasSourceEditor::_tile_atlas_control_draw() {
+	// Draw the selected tile.
+	if (tools_button_group->get_pressed_button() == tool_select_button) {
+		for (Set<TileSelection>::Element *E = selection.front(); E; E = E->next()) {
+			TileSelection selected = E->get();
+			if (selected.alternative == 0) {
+				// Draw the rect.
+				Rect2 region = tile_set_atlas_source->get_tile_texture_region(selected.tile);
+				tile_atlas_control->draw_rect(region, Color(0.2, 0.2, 1.0), false);
+			}
+		}
+
+		if (selection.size() == 1) {
+			// Draw the resize handles (only when it's possible to expand).
+			TileSelection selected = selection.front()->get();
+			Vector2i size_in_atlas = tile_set_atlas_source->get_tile_size_in_atlas(selected.tile);
+			Size2 zoomed_size = resize_handle->get_size() / tile_atlas_view->get_zoom();
+			Rect2 region = tile_set_atlas_source->get_tile_texture_region(selected.tile);
+			Rect2 rect = region.grow_individual(zoomed_size.x, zoomed_size.y, 0, 0);
+			Vector2i coords[] = { Vector2i(0, 0), Vector2i(1, 0), Vector2i(1, 1), Vector2i(0, 1) };
+			Vector2i directions[] = { Vector2i(0, -1), Vector2i(1, 0), Vector2i(0, 1), Vector2i(-1, 0) };
+			bool can_grow[4];
+			for (int i = 0; i < 4; i++) {
+				can_grow[i] = tile_set_atlas_source->can_move_tile_in_atlas(selected.tile, selected.tile + directions[i]);
+				can_grow[i] |= (i % 2 == 0) ? size_in_atlas.y > 1 : size_in_atlas.x > 1;
+			}
+			for (int i = 0; i < 4; i++) {
+				Vector2 pos = rect.position + Vector2(rect.size.x, rect.size.y) * coords[i];
+				if (can_grow[i] && can_grow[(i + 3) % 4]) {
+					tile_atlas_control->draw_texture_rect(resize_handle, Rect2(pos, zoomed_size), false);
+				} else {
+					tile_atlas_control->draw_texture_rect(resize_handle_disabled, Rect2(pos, zoomed_size), false);
+				}
+				Vector2 next_pos = rect.position + Vector2(rect.size.x, rect.size.y) * coords[(i + 1) % 4];
+				if (can_grow[i]) {
+					tile_atlas_control->draw_texture_rect(resize_handle, Rect2((pos + next_pos) / 2.0, zoomed_size), false);
+				} else {
+					tile_atlas_control->draw_texture_rect(resize_handle_disabled, Rect2((pos + next_pos) / 2.0, zoomed_size), false);
+				}
+			}
+		}
+	}
+
+	if (drag_type == DRAG_TYPE_REMOVE_TILES) {
+		// Draw the tiles to be removed.
+		for (Set<Vector2i>::Element *E = drag_modified_tiles.front(); E; E = E->next()) {
+			tile_atlas_control->draw_rect(tile_set_atlas_source->get_tile_texture_region(E->get()), Color(0.0, 0.0, 0.0), false);
+		}
+	} else if (drag_type == DRAG_TYPE_RECT_SELECT || drag_type == DRAG_TYPE_REMOVE_TILES_USING_RECT) {
+		// Draw tiles to be removed.
+		Vector2i start_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+		Vector2i new_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+		Rect2i area = Rect2i(start_base_tiles_coords, new_base_tiles_coords - start_base_tiles_coords).abs();
+		area.set_end((area.get_end() + Vector2i(1, 1)).min(tile_set_atlas_source->get_atlas_grid_size()));
+
+		Color color = Color(0.0, 0.0, 0.0);
+		if (drag_type == DRAG_TYPE_RECT_SELECT) {
+			color = Color(0.5, 0.5, 1.0);
+		}
+
+		Set<Vector2i> to_paint;
+		for (int x = area.get_position().x; x < area.get_end().x; x++) {
+			for (int y = area.get_position().y; y < area.get_end().y; y++) {
+				Vector2i coords = tile_set_atlas_source->get_tile_at_coords(Vector2i(x, y));
+				if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					to_paint.insert(coords);
+				}
+			}
+		}
+
+		for (Set<Vector2i>::Element *E = to_paint.front(); E; E = E->next()) {
+			Vector2i coords = E->get();
+			tile_atlas_control->draw_rect(tile_set_atlas_source->get_tile_texture_region(coords), color, false);
+		}
+	} else if (drag_type == DRAG_TYPE_CREATE_TILES_USING_RECT) {
+		// Draw tiles to be created.
+		Vector2i margins = tile_set_atlas_source->get_margins();
+		Vector2i separation = tile_set_atlas_source->get_separation();
+		Vector2i tile_size = tile_set_atlas_source->get_texture_region_size();
+
+		Vector2i start_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+		Vector2i new_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+		Rect2i area = Rect2i(start_base_tiles_coords, new_base_tiles_coords - start_base_tiles_coords).abs();
+		area.set_end((area.get_end() + Vector2i(1, 1)).min(tile_set_atlas_source->get_atlas_grid_size()));
+		for (int x = area.get_position().x; x < area.get_end().x; x++) {
+			for (int y = area.get_position().y; y < area.get_end().y; y++) {
+				Vector2i coords = Vector2i(x, y);
+				if (tile_set_atlas_source->get_tile_at_coords(coords) == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					Vector2i origin = margins + (coords * (tile_size + separation));
+					tile_atlas_control->draw_rect(Rect2i(origin, tile_size), Color(1.0, 1.0, 1.0), false);
+				}
+			}
+		}
+	}
+
+	// Draw the hovered tile.
+	if (drag_type == DRAG_TYPE_REMOVE_TILES_USING_RECT || drag_type == DRAG_TYPE_CREATE_TILES_USING_RECT) {
+		// Draw the rect.
+		Vector2i start_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(drag_start_mouse_pos);
+		Vector2i new_base_tiles_coords = tile_atlas_view->get_atlas_tile_coords_at_pos(tile_atlas_control->get_local_mouse_position());
+		Rect2i area = Rect2i(start_base_tiles_coords, new_base_tiles_coords - start_base_tiles_coords).abs();
+		area.set_end((area.get_end() + Vector2i(1, 1)).min(tile_set_atlas_source->get_atlas_grid_size()));
+		Vector2i margins = tile_set_atlas_source->get_margins();
+		Vector2i separation = tile_set_atlas_source->get_separation();
+		Vector2i tile_size = tile_set_atlas_source->get_texture_region_size();
+		Vector2i origin = margins + (area.position * (tile_size + separation));
+		tile_atlas_control->draw_rect(Rect2i(origin, area.size * tile_size), Color(1.0, 1.0, 1.0), false);
+	} else {
+		Vector2i grid_size = tile_set_atlas_source->get_atlas_grid_size();
+		if (hovered_base_tile_coords.x >= 0 && hovered_base_tile_coords.y >= 0 && hovered_base_tile_coords.x < grid_size.x && hovered_base_tile_coords.y < grid_size.y) {
+			Vector2i hovered_tile = tile_set_atlas_source->get_tile_at_coords(hovered_base_tile_coords);
+			if (hovered_tile != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+				// Draw existing hovered tile.
+				tile_atlas_control->draw_rect(tile_set_atlas_source->get_tile_texture_region(hovered_tile), Color(1.0, 1.0, 1.0), false);
+			} else {
+				// Draw empty tile, only in add/remove tiles mode.
+				if (tools_button_group->get_pressed_button() == tool_add_remove_button || tools_button_group->get_pressed_button() == tool_add_remove_rect_button) {
+					Vector2i margins = tile_set_atlas_source->get_margins();
+					Vector2i separation = tile_set_atlas_source->get_separation();
+					Vector2i tile_size = tile_set_atlas_source->get_texture_region_size();
+					Vector2i origin = margins + (hovered_base_tile_coords * (tile_size + separation));
+					tile_atlas_control->draw_rect(Rect2i(origin, tile_size), Color(1.0, 1.0, 1.0), false);
+				}
+			}
+		}
+	}
+}
+
+void TileSetAtlasSourceEditor::_tile_atlas_control_unscaled_draw() {
+	// Draw the preview of the selected property.
+	TileDataEditor *tile_data_editor = TileSetEditor::get_singleton()->get_tile_data_editor(selected_property);
+	if (tile_data_editor && tile_inspector->is_visible_in_tree()) {
+		for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+			Vector2i coords = tile_set_atlas_source->get_tile_id(i);
+			Rect2i texture_region = tile_set_atlas_source->get_tile_texture_region(coords);
+			Vector2i position = (texture_region.position + texture_region.get_end()) / 2 + tile_set_atlas_source->get_tile_effective_texture_offset(coords, 0);
+
+			Transform2D xform = tile_atlas_control->get_parent_control()->get_transform();
+			xform.translate(position);
+
+			tile_data_editor->draw_over_tile(tile_atlas_control_unscaled, xform, *tile_set, tile_set_atlas_source_id, coords, 0, selected_property);
+		}
+	}
+}
+
+void TileSetAtlasSourceEditor::_tile_alternatives_control_gui_input(const Ref<InputEvent> &p_event) {
+	// Update the hovered alternative tile.
+	hovered_alternative_tile_coords = tile_atlas_view->get_alternative_tile_at_pos(alternative_tiles_control->get_local_mouse_position());
+
+	Ref<InputEventMouseMotion> mm = p_event;
+	if (mm.is_valid()) {
+		tile_atlas_control->update();
+		tile_atlas_control_unscaled->update();
+		alternative_tiles_control->update();
+		alternative_tiles_control_unscaled->update();
+	}
+
+	Ref<InputEventMouseButton> mb = p_event;
+	if (mb.is_valid()) {
+		drag_type = DRAG_TYPE_NONE;
+
+		Vector2 mouse_local_pos = alternative_tiles_control->get_local_mouse_position();
+		if (mb->get_button_index() == MOUSE_BUTTON_LEFT) {
+			if (mb->is_pressed()) {
+				// Left click pressed.
+				if (tools_button_group->get_pressed_button() == tool_select_button) {
+					Vector3 tile = tile_atlas_view->get_alternative_tile_at_pos(mouse_local_pos);
+
+					selection.clear();
+					TileSelection selected = { Vector2i(tile.x, tile.y), int(tile.z) };
+					if (selected.tile != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+						selection.insert(selected);
+					}
+
+					_update_tile_inspector();
+					_update_tile_id_label();
+				}
+			}
+		} else if (mb->get_button_index() == MOUSE_BUTTON_RIGHT) {
+			if (mb->is_pressed()) {
+				// Right click pressed
+				Vector3 tile = tile_atlas_view->get_alternative_tile_at_pos(mouse_local_pos);
+
+				selection.clear();
+				TileSelection selected = { Vector2i(tile.x, tile.y), int(tile.z) };
+				if (selected.tile != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					selection.insert(selected);
+				}
+
+				_update_tile_inspector();
+				_update_tile_id_label();
+
+				if (selection.size() == 1) {
+					selected = selection.front()->get();
+					menu_option_coords = selected.tile;
+					menu_option_alternative = selected.alternative;
+					alternative_tile_popup_menu->popup(Rect2i(get_global_mouse_position(), Size2i()));
+				}
+			}
+		}
+		tile_atlas_control->update();
+		tile_atlas_control_unscaled->update();
+		alternative_tiles_control->update();
+		alternative_tiles_control_unscaled->update();
+	}
+}
+
+void TileSetAtlasSourceEditor::_tile_alternatives_control_mouse_exited() {
+	hovered_alternative_tile_coords = Vector3i(TileSetAtlasSource::INVALID_ATLAS_COORDS.x, TileSetAtlasSource::INVALID_ATLAS_COORDS.y, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+	tile_atlas_control->update();
+	tile_atlas_control_unscaled->update();
+	alternative_tiles_control->update();
+	alternative_tiles_control_unscaled->update();
+}
+
+void TileSetAtlasSourceEditor::_tile_alternatives_control_draw() {
+	// Update the hovered alternative tile.
+	if (tools_button_group->get_pressed_button() == tool_select_button) {
+		// Draw hovered tile.
+		Vector2i coords = Vector2(hovered_alternative_tile_coords.x, hovered_alternative_tile_coords.y);
+		if (coords != TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+			Rect2i rect = tile_atlas_view->get_alternative_tile_rect(coords, hovered_alternative_tile_coords.z);
+			if (rect != Rect2i()) {
+				alternative_tiles_control->draw_rect(rect, Color(1.0, 1.0, 1.0), false);
+			}
+		}
+
+		// Draw selected tile.
+		for (Set<TileSelection>::Element *E = selection.front(); E; E = E->next()) {
+			TileSelection selected = E->get();
+			if (selected.alternative >= 1) {
+				Rect2i rect = tile_atlas_view->get_alternative_tile_rect(selected.tile, selected.alternative);
+				if (rect != Rect2i()) {
+					alternative_tiles_control->draw_rect(rect, Color(0.2, 0.2, 1.0), false);
+				}
+			}
+		}
+	}
+}
+
+void TileSetAtlasSourceEditor::_tile_alternatives_control_unscaled_draw() {
+	//TODO
+}
+
+void TileSetAtlasSourceEditor::_tile_set_atlas_source_changed() {
+	tile_set_atlas_source_changed_needs_update = true;
+}
+
+void TileSetAtlasSourceEditor::_atlas_source_proxy_object_changed(String p_what) {
+	if (p_what == "texture" && !atlas_source_proxy_object->get("texture").is_null()) {
+		confirm_auto_create_tiles->popup_centered();
+	} else if (p_what == "id") {
+		emit_signal("source_id_changed", atlas_source_proxy_object->get_id());
+	}
+}
+
+void TileSetAtlasSourceEditor::_undo_redo_inspector_callback(Object *p_undo_redo, Object *p_edited, String p_property, Variant p_new_value) {
+	UndoRedo *undo_redo = Object::cast_to<UndoRedo>(p_undo_redo);
+	ERR_FAIL_COND(!undo_redo);
+
+#define ADD_UNDO(obj, property) undo_redo->add_undo_property(obj, property, tile_data->get(property));
+
+	TileProxyObject *tile_data = Object::cast_to<TileProxyObject>(p_edited);
+	if (tile_data) {
+		Vector<String> components = String(p_property).split("/", true, 2);
+		if (components.size() == 2 && components[1] == "shapes_count") {
+			int layer_index = components[0].trim_prefix("physics_layer_").to_int();
+			int new_shapes_count = p_new_value;
+			int old_shapes_count = tile_data->get(vformat("physics_layer_%d/shapes_count", layer_index));
+			if (new_shapes_count < old_shapes_count) {
+				for (int i = new_shapes_count - 1; i < old_shapes_count; i++) {
+					ADD_UNDO(tile_data, vformat("physics_layer_%d/shape_%d/shape", layer_index, i));
+					ADD_UNDO(tile_data, vformat("physics_layer_%d/shape_%d/one_way", layer_index, i));
+					ADD_UNDO(tile_data, vformat("physics_layer_%d/shape_%d/one_way_margin", layer_index, i));
+				}
+			}
+		}
+	}
+#undef ADD_UNDO
+}
+
+void TileSetAtlasSourceEditor::edit(Ref<TileSet> p_tile_set, TileSetAtlasSource *p_tile_set_atlas_source, int p_source_id) {
+	ERR_FAIL_COND(!p_tile_set.is_valid());
+	ERR_FAIL_COND(!p_tile_set_atlas_source);
+	ERR_FAIL_COND(p_source_id < 0);
+	ERR_FAIL_COND(p_tile_set->get_source(p_source_id) != p_tile_set_atlas_source);
+
+	if (p_tile_set == tile_set && p_tile_set_atlas_source == tile_set_atlas_source && p_source_id == tile_set_atlas_source_id) {
+		return;
+	}
+
+	// Remove listener for old objects.
+	if (tile_set_atlas_source) {
+		tile_set_atlas_source->disconnect("changed", callable_mp(this, &TileSetAtlasSourceEditor::_tile_set_atlas_source_changed));
+	}
+
+	// Clear the selection.
+	selection.clear();
+
+	// Change the edited object.
+	tile_set = p_tile_set;
+	tile_set_atlas_source = p_tile_set_atlas_source;
+	tile_set_atlas_source_id = p_source_id;
+
+	// Add the listener again.
+	if (tile_set_atlas_source) {
+		tile_set_atlas_source->connect("changed", callable_mp(this, &TileSetAtlasSourceEditor::_tile_set_atlas_source_changed));
+	}
+
+	// Update everything.
+	_update_source_inspector();
+
+	// Update the selected tile.
+	_update_fix_selected_and_hovered_tiles();
+	_update_tile_id_label();
+	_update_atlas_view();
+	_update_tile_inspector();
+}
+
+void TileSetAtlasSourceEditor::init_source() {
+	confirm_auto_create_tiles->popup_centered();
+}
+
+void TileSetAtlasSourceEditor::_auto_create_tiles() {
+	if (!tile_set_atlas_source) {
+		return;
+	}
+
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+	if (texture.is_valid()) {
+		Vector2i margins = tile_set_atlas_source->get_margins();
+		Vector2i separation = tile_set_atlas_source->get_separation();
+		Vector2i texture_region_size = tile_set_atlas_source->get_texture_region_size();
+		Size2i grid_size = tile_set_atlas_source->get_atlas_grid_size();
+		undo_redo->create_action(TTR("Create tiles in non-transparent texture regions"));
+		for (int y = 0; y < grid_size.y; y++) {
+			for (int x = 0; x < grid_size.x; x++) {
+				// Check if we have a tile at the coord
+				Vector2i coords = Vector2i(x, y);
+				if (tile_set_atlas_source->get_tile_at_coords(coords) == TileSetAtlasSource::INVALID_ATLAS_COORDS) {
+					// Check if the texture is empty at the given coords.
+					Rect2i region = Rect2i(margins + (coords * (texture_region_size + separation)), texture_region_size);
+					bool is_opaque = false;
+					for (int region_x = region.get_position().x; region_x < region.get_end().x; region_x++) {
+						for (int region_y = region.get_position().y; region_y < region.get_end().y; region_y++) {
+							if (texture->is_pixel_opaque(region_x, region_y)) {
+								is_opaque = true;
+								break;
+							}
+						}
+						if (is_opaque) {
+							break;
+						}
+					}
+
+					// If we do have opaque pixels, create a tile.
+					if (is_opaque) {
+						undo_redo->add_do_method(tile_set_atlas_source, "create_tile", coords);
+						undo_redo->add_undo_method(tile_set_atlas_source, "remove_tile", coords);
+					}
+				}
+			}
+		}
+		undo_redo->commit_action();
+	}
+}
+
+void TileSetAtlasSourceEditor::_auto_remove_tiles() {
+	if (!tile_set_atlas_source) {
+		return;
+	}
+
+	Ref<Texture2D> texture = tile_set_atlas_source->get_texture();
+	if (texture.is_valid()) {
+		Vector2i margins = tile_set_atlas_source->get_margins();
+		Vector2i separation = tile_set_atlas_source->get_separation();
+		Vector2i texture_region_size = tile_set_atlas_source->get_texture_region_size();
+		Vector2i grid_size = tile_set_atlas_source->get_atlas_grid_size();
+
+		undo_redo->create_action(TTR("Remove tiles in fully transparent texture regions"));
+
+		List<PropertyInfo> list;
+		tile_set_atlas_source->get_property_list(&list);
+		Map<Vector2i, List<const PropertyInfo *>> per_tile = _group_properties_per_tiles(list, tile_set_atlas_source);
+
+		for (int i = 0; i < tile_set_atlas_source->get_tiles_count(); i++) {
+			Vector2i coords = tile_set_atlas_source->get_tile_id(i);
+			Vector2i size_in_atlas = tile_set_atlas_source->get_tile_size_in_atlas(coords);
+
+			// Skip tiles outside texture.
+			if ((coords.x + size_in_atlas.x) > grid_size.x || (coords.y + size_in_atlas.y) > grid_size.y) {
+				continue;
+			}
+
+			// Check if the texture is empty at the given coords.
+			Rect2i region = Rect2i(margins + (coords * (texture_region_size + separation)), texture_region_size * size_in_atlas);
+			bool is_opaque = false;
+			for (int region_x = region.get_position().x; region_x < region.get_end().x; region_x++) {
+				for (int region_y = region.get_position().y; region_y < region.get_end().y; region_y++) {
+					if (texture->is_pixel_opaque(region_x, region_y)) {
+						is_opaque = true;
+						break;
+					}
+				}
+				if (is_opaque) {
+					break;
+				}
+			}
+
+			// If we do have opaque pixels, create a tile.
+			if (!is_opaque) {
+				undo_redo->add_do_method(tile_set_atlas_source, "remove_tile", coords);
+				undo_redo->add_undo_method(tile_set_atlas_source, "create_tile", coords);
+				if (per_tile.has(coords)) {
+					for (List<const PropertyInfo *>::Element *E_property = per_tile[coords].front(); E_property; E_property = E_property->next()) {
+						String property = E_property->get()->name;
+						Variant value = tile_set_atlas_source->get(property);
+						if (value.get_type() != Variant::NIL) {
+							undo_redo->add_undo_method(tile_set_atlas_source, "set", E_property->get()->name, value);
+						}
+					}
+				}
+			}
+		}
+		undo_redo->commit_action();
+	}
+}
+
+void TileSetAtlasSourceEditor::_notification(int p_what) {
+	switch (p_what) {
+		case NOTIFICATION_ENTER_TREE:
+		case NOTIFICATION_THEME_CHANGED:
+			tool_select_button->set_icon(get_theme_icon("ToolSelect", "EditorIcons"));
+			tool_add_remove_button->set_icon(get_theme_icon("EditAddRemove", "EditorIcons"));
+			tool_add_remove_rect_button->set_icon(get_theme_icon("RectangleAddRemove", "EditorIcons"));
+
+			tools_settings_erase_button->set_icon(get_theme_icon("Eraser", "EditorIcons"));
+
+			tool_advanced_menu_buttom->set_icon(get_theme_icon("Tools", "EditorIcons"));
+
+			resize_handle = get_theme_icon("EditorHandle", "EditorIcons");
+			resize_handle_disabled = get_theme_icon("EditorHandleDisabled", "EditorIcons");
+			break;
+		case NOTIFICATION_INTERNAL_PROCESS:
+			if (tile_set_atlas_source_changed_needs_update) {
+				// Update everything.
+				_update_source_inspector();
+
+				// Update the selected tile.
+				_update_fix_selected_and_hovered_tiles();
+				_update_tile_id_label();
+				_update_atlas_view();
+				_update_tile_inspector();
+
+				tile_set_atlas_source_changed_needs_update = false;
+			}
+			break;
+		default:
+			break;
+	}
+}
+
+void TileSetAtlasSourceEditor::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("_unhandled_key_input"), &TileSetAtlasSourceEditor::_unhandled_key_input);
+	ClassDB::bind_method(D_METHOD("_set_selection_from_array"), &TileSetAtlasSourceEditor::_set_selection_from_array);
+
+	ADD_SIGNAL(MethodInfo("source_id_changed", PropertyInfo(Variant::INT, "source_id")));
+}
+
+TileSetAtlasSourceEditor::TileSetAtlasSourceEditor() {
+	set_process_unhandled_key_input(true);
+	set_process_internal(true);
+
+	// -- Right side --
+	HSplitContainer *split_container_right_side = memnew(HSplitContainer);
+	split_container_right_side->set_h_size_flags(SIZE_EXPAND_FILL);
+	add_child(split_container_right_side);
+
+	// Middle panel.
+	ScrollContainer *middle_panel = memnew(ScrollContainer);
+	middle_panel->set_enable_h_scroll(false);
+	middle_panel->set_custom_minimum_size(Size2i(200, 0) * EDSCALE);
+	split_container_right_side->add_child(middle_panel);
+
+	VBoxContainer *middle_vbox_container = memnew(VBoxContainer);
+	middle_vbox_container->set_h_size_flags(SIZE_EXPAND_FILL);
+	middle_panel->add_child(middle_vbox_container);
+
+	// Tile inspector.
+	tile_inspector_label = memnew(Label);
+	tile_inspector_label->set_text(TTR("Tile properties:"));
+	tile_inspector_label->hide();
+	middle_vbox_container->add_child(tile_inspector_label);
+
+	tile_proxy_object = memnew(TileProxyObject(this));
+	tile_proxy_object->connect("changed", callable_mp(this, &TileSetAtlasSourceEditor::_update_atlas_view).unbind(1));
+
+	tile_inspector = memnew(EditorInspector);
+	tile_inspector->set_undo_redo(undo_redo);
+	tile_inspector->set_enable_v_scroll(false);
+	tile_inspector->edit(tile_proxy_object);
+	tile_inspector->set_use_folding(true);
+	tile_inspector->connect("property_selected", callable_mp(this, &TileSetAtlasSourceEditor::_inspector_property_selected));
+	middle_vbox_container->add_child(tile_inspector);
+
+	// Atlas source inspector.
+	atlas_source_inspector_label = memnew(Label);
+	atlas_source_inspector_label->set_text(TTR("Atlas properties:"));
+	middle_vbox_container->add_child(atlas_source_inspector_label);
+
+	atlas_source_proxy_object = memnew(TileSetAtlasSourceProxyObject());
+	atlas_source_proxy_object->connect("changed", callable_mp(this, &TileSetAtlasSourceEditor::_atlas_source_proxy_object_changed));
+
+	atlas_source_inspector = memnew(EditorInspector);
+	atlas_source_inspector->set_undo_redo(undo_redo);
+	atlas_source_inspector->set_enable_v_scroll(false);
+	atlas_source_inspector->edit(atlas_source_proxy_object);
+	middle_vbox_container->add_child(atlas_source_inspector);
+
+	// Right panel.
+	VBoxContainer *right_panel = memnew(VBoxContainer);
+	right_panel->set_h_size_flags(SIZE_EXPAND_FILL);
+	right_panel->set_v_size_flags(SIZE_EXPAND_FILL);
+	split_container_right_side->add_child(right_panel);
+
+	// -- Dialogs --
+	confirm_auto_create_tiles = memnew(AcceptDialog);
+	confirm_auto_create_tiles->set_title(TTR("Create tiles automatically in non-transparent texture regions?"));
+	confirm_auto_create_tiles->set_text(TTR("The atlas's texture was modified.\nWould you like to automatically create tiles in the atlas?"));
+	confirm_auto_create_tiles->get_ok_button()->set_text(TTR("Yes"));
+	confirm_auto_create_tiles->add_cancel_button()->set_text(TTR("No"));
+	confirm_auto_create_tiles->connect("confirmed", callable_mp(this, &TileSetAtlasSourceEditor::_auto_create_tiles));
+	add_child(confirm_auto_create_tiles);
+
+	// -- Toolbox --
+	tools_button_group.instance();
+
+	toolbox = memnew(HBoxContainer);
+	right_panel->add_child(toolbox);
+
+	tool_select_button = memnew(Button);
+	tool_select_button->set_flat(true);
+	tool_select_button->set_toggle_mode(true);
+	tool_select_button->set_pressed(true);
+	tool_select_button->set_button_group(tools_button_group);
+	tool_select_button->set_tooltip(TTR("Select tiles"));
+	tool_select_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_fix_selected_and_hovered_tiles));
+	tool_select_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_tile_id_label));
+	tool_select_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_tile_inspector));
+	tool_select_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_atlas_view));
+	tool_select_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_toolbar));
+	toolbox->add_child(tool_select_button);
+
+	tool_add_remove_button = memnew(Button);
+	tool_add_remove_button->set_flat(true);
+	tool_add_remove_button->set_toggle_mode(true);
+	tool_add_remove_button->set_button_group(tools_button_group);
+	tool_add_remove_button->set_tooltip(TTR("Add/Remove tiles tool (use the shift key to create big tiles)"));
+	tool_add_remove_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_fix_selected_and_hovered_tiles));
+	tool_add_remove_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_tile_id_label));
+	tool_add_remove_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_tile_inspector));
+	tool_add_remove_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_atlas_view));
+	tool_add_remove_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_toolbar));
+	toolbox->add_child(tool_add_remove_button);
+
+	tool_add_remove_rect_button = memnew(Button);
+	tool_add_remove_rect_button->set_flat(true);
+	tool_add_remove_rect_button->set_toggle_mode(true);
+	tool_add_remove_rect_button->set_button_group(tools_button_group);
+	tool_add_remove_rect_button->set_tooltip(TTR("Add/Remove tiles rectangle tool (use the shift key to create big tiles)"));
+	tool_add_remove_rect_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_fix_selected_and_hovered_tiles));
+	tool_add_remove_rect_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_tile_id_label));
+	tool_add_remove_rect_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_tile_inspector));
+	tool_add_remove_rect_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_atlas_view));
+	tool_add_remove_rect_button->connect("pressed", callable_mp(this, &TileSetAtlasSourceEditor::_update_toolbar));
+	toolbox->add_child(tool_add_remove_rect_button);
+
+	// Tool settings.
+	tool_settings = memnew(HBoxContainer);
+	toolbox->add_child(tool_settings);
+
+	tool_settings_vsep = memnew(VSeparator);
+	tool_settings->add_child(tool_settings_vsep);
+
+	tools_settings_erase_button = memnew(Button);
+	tools_settings_erase_button->set_flat(true);
+	tools_settings_erase_button->set_toggle_mode(true);
+	tools_settings_erase_button->set_shortcut(ED_SHORTCUT("tiles_editor/eraser", "Eraser", KEY_E));
+	tools_settings_erase_button->set_shortcut_context(this);
+	tool_settings->add_child(tools_settings_erase_button);
+
+	VSeparator *tool_advanced_vsep = memnew(VSeparator);
+	toolbox->add_child(tool_advanced_vsep);
+
+	tool_advanced_menu_buttom = memnew(MenuButton);
+	tool_advanced_menu_buttom->set_flat(true);
+	tool_advanced_menu_buttom->get_popup()->add_item(TTR("Cleanup tiles outside texture"), ADVANCED_CLEANUP_TILES_OUTSIDE_TEXTURE);
+	tool_advanced_menu_buttom->get_popup()->set_item_disabled(0, true);
+	tool_advanced_menu_buttom->get_popup()->add_item(TTR("Create tiles in non-transparent texture regions."), ADVANCED_AUTO_CREATE_TILES);
+	tool_advanced_menu_buttom->get_popup()->add_item(TTR("Remove tiles in fully transparent texture regions."), ADVANCED_AUTO_REMOVE_TILES);
+	tool_advanced_menu_buttom->get_popup()->connect("id_pressed", callable_mp(this, &TileSetAtlasSourceEditor::_menu_option));
+	toolbox->add_child(tool_advanced_menu_buttom);
+
+	_update_toolbar();
+
+	// Right side of toolbar.
+	Control *middle_space = memnew(Control);
+	middle_space->set_h_size_flags(SIZE_EXPAND_FILL);
+	toolbox->add_child(middle_space);
+
+	tool_tile_id_label = memnew(Label);
+	tool_tile_id_label->set_mouse_filter(Control::MOUSE_FILTER_STOP);
+	toolbox->add_child(tool_tile_id_label);
+	_update_tile_id_label();
+
+	// Tile atlas view.
+	tile_atlas_view = memnew(TileAtlasView);
+	tile_atlas_view->set_h_size_flags(SIZE_EXPAND_FILL);
+	tile_atlas_view->set_v_size_flags(SIZE_EXPAND_FILL);
+	tile_atlas_view->connect("transform_changed", callable_mp(TilesEditor::get_singleton(), &TilesEditor::set_atlas_view_transform));
+	tile_atlas_view->connect("transform_changed", callable_mp(this, &TileSetAtlasSourceEditor::_tile_atlas_view_transform_changed).unbind(2));
+	right_panel->add_child(tile_atlas_view);
+
+	base_tile_popup_menu = memnew(PopupMenu);
+	base_tile_popup_menu->add_shortcut(ED_SHORTCUT("tiles_editor/delete", TTR("Delete"), KEY_DELETE), TILE_DELETE);
+	base_tile_popup_menu->add_item(TTR("Create an Alternative Tile"), TILE_CREATE_ALTERNATIVE);
+	base_tile_popup_menu->connect("id_pressed", callable_mp(this, &TileSetAtlasSourceEditor::_menu_option));
+	tile_atlas_view->add_child(base_tile_popup_menu);
+
+	empty_base_tile_popup_menu = memnew(PopupMenu);
+	empty_base_tile_popup_menu->add_item(TTR("Create a Tile"), TILE_CREATE);
+	empty_base_tile_popup_menu->connect("id_pressed", callable_mp(this, &TileSetAtlasSourceEditor::_menu_option));
+	tile_atlas_view->add_child(empty_base_tile_popup_menu);
+
+	tile_atlas_control = memnew(Control);
+	tile_atlas_control->connect("draw", callable_mp(this, &TileSetAtlasSourceEditor::_tile_atlas_control_draw));
+	tile_atlas_control->connect("mouse_exited", callable_mp(this, &TileSetAtlasSourceEditor::_tile_atlas_control_mouse_exited));
+	tile_atlas_control->connect("gui_input", callable_mp(this, &TileSetAtlasSourceEditor::_tile_atlas_control_gui_input));
+	tile_atlas_view->add_control_over_atlas_tiles(tile_atlas_control);
+
+	tile_atlas_control_unscaled = memnew(Control);
+	tile_atlas_control_unscaled->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	tile_atlas_control_unscaled->connect("draw", callable_mp(this, &TileSetAtlasSourceEditor::_tile_atlas_control_unscaled_draw));
+	tile_atlas_view->add_control_over_atlas_tiles(tile_atlas_control_unscaled, false);
+	tile_atlas_control_unscaled->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+
+	alternative_tile_popup_menu = memnew(PopupMenu);
+	alternative_tile_popup_menu->add_shortcut(ED_SHORTCUT("tiles_editor/delete_tile", TTR("Delete"), KEY_DELETE), TILE_DELETE);
+	alternative_tile_popup_menu->connect("id_pressed", callable_mp(this, &TileSetAtlasSourceEditor::_menu_option));
+	tile_atlas_view->add_child(alternative_tile_popup_menu);
+
+	alternative_tiles_control = memnew(Control);
+	alternative_tiles_control->connect("draw", callable_mp(this, &TileSetAtlasSourceEditor::_tile_alternatives_control_draw));
+	alternative_tiles_control->connect("mouse_exited", callable_mp(this, &TileSetAtlasSourceEditor::_tile_alternatives_control_mouse_exited));
+	alternative_tiles_control->connect("gui_input", callable_mp(this, &TileSetAtlasSourceEditor::_tile_alternatives_control_gui_input));
+	tile_atlas_view->add_control_over_alternative_tiles(alternative_tiles_control);
+
+	alternative_tiles_control_unscaled = memnew(Control);
+	alternative_tiles_control_unscaled->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+	alternative_tiles_control_unscaled->connect("draw", callable_mp(this, &TileSetAtlasSourceEditor::_tile_alternatives_control_unscaled_draw));
+	tile_atlas_view->add_control_over_atlas_tiles(alternative_tiles_control_unscaled, false);
+	alternative_tiles_control_unscaled->set_mouse_filter(Control::MOUSE_FILTER_IGNORE);
+
+	tile_atlas_view_missing_source_label = memnew(Label);
+	tile_atlas_view_missing_source_label->set_text(TTR("Add or select an atlas texture to the left panel."));
+	tile_atlas_view_missing_source_label->set_align(Label::ALIGN_CENTER);
+	tile_atlas_view_missing_source_label->set_valign(Label::VALIGN_CENTER);
+	tile_atlas_view_missing_source_label->set_h_size_flags(SIZE_EXPAND_FILL);
+	tile_atlas_view_missing_source_label->set_v_size_flags(SIZE_EXPAND_FILL);
+	tile_atlas_view_missing_source_label->hide();
+	right_panel->add_child(tile_atlas_view_missing_source_label);
+}
+
+TileSetAtlasSourceEditor::~TileSetAtlasSourceEditor() {
+	memdelete(tile_proxy_object);
+	memdelete(atlas_source_proxy_object);
+}
diff --git a/editor/plugins/tiles/tile_set_atlas_source_editor.h b/editor/plugins/tiles/tile_set_atlas_source_editor.h
new file mode 100644
index 0000000000..ff68aa8288
--- /dev/null
+++ b/editor/plugins/tiles/tile_set_atlas_source_editor.h
@@ -0,0 +1,260 @@
+/*************************************************************************/
+/*  tile_set_atlas_source_editor.h                                       */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef TILE_SET_ATLAS_SOURCE_EDITOR_H
+#define TILE_SET_ATLAS_SOURCE_EDITOR_H
+
+#include "tile_atlas_view.h"
+
+#include "editor/editor_node.h"
+#include "scene/gui/split_container.h"
+#include "scene/resources/tile_set.h"
+
+class TileSet;
+
+class TileSetAtlasSourceEditor : public HBoxContainer {
+	GDCLASS(TileSetAtlasSourceEditor, HBoxContainer);
+
+private:
+	// A class to store which tiles are selected.
+	struct TileSelection {
+		Vector2i tile = TileSetAtlasSource::INVALID_ATLAS_COORDS;
+		int alternative = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+
+		bool operator<(const TileSelection &p_other) const {
+			if (tile == p_other.tile) {
+				return alternative < p_other.alternative;
+			} else {
+				return tile < p_other.tile;
+			}
+		}
+	};
+
+	// -- Proxy object for an atlas source, needed by the inspector --
+	class TileSetAtlasSourceProxyObject : public Object {
+		GDCLASS(TileSetAtlasSourceProxyObject, Object);
+
+	private:
+		Ref<TileSet> tile_set;
+		TileSetAtlasSource *tile_set_atlas_source = nullptr;
+		int source_id = -1;
+
+	protected:
+		bool _set(const StringName &p_name, const Variant &p_value);
+		bool _get(const StringName &p_name, Variant &r_ret) const;
+		void _get_property_list(List<PropertyInfo> *p_list) const;
+		static void _bind_methods();
+
+	public:
+		void set_id(int p_id);
+		int get_id();
+
+		void edit(Ref<TileSet> p_tile_set, TileSetAtlasSource *p_tile_set_atlas_source, int p_source_id);
+	};
+
+	// -- Proxy object for a tile, needed by the inspector --
+	class TileProxyObject : public Object {
+		GDCLASS(TileProxyObject, Object);
+
+	private:
+		TileSetAtlasSourceEditor *tiles_set_atlas_source_editor;
+
+		TileSetAtlasSource *tile_set_atlas_source = nullptr;
+		int source_id;
+		Set<TileSelection> tiles = Set<TileSelection>();
+
+	protected:
+		bool _set(const StringName &p_name, const Variant &p_value);
+		bool _get(const StringName &p_name, Variant &r_ret) const;
+		void _get_property_list(List<PropertyInfo> *p_list) const;
+
+		static void _bind_methods();
+
+	public:
+		// Update the proxyed object.
+		void edit(TileSetAtlasSource *p_tile_set_atlas_source, int p_source_id = -1, Set<TileSelection> p_tiles = Set<TileSelection>());
+
+		TileProxyObject(TileSetAtlasSourceEditor *p_tiles_editor_source_tab) {
+			tiles_set_atlas_source_editor = p_tiles_editor_source_tab;
+		}
+	};
+
+	Ref<TileSet> tile_set;
+	TileSetAtlasSource *tile_set_atlas_source = nullptr;
+	int tile_set_atlas_source_id = -1;
+
+	UndoRedo *undo_redo = EditorNode::get_undo_redo();
+
+	bool tile_set_atlas_source_changed_needs_update = false;
+
+	// -- Inspector --
+	TileProxyObject *tile_proxy_object;
+	Label *tile_inspector_label;
+	EditorInspector *tile_inspector;
+	String selected_property;
+	void _inspector_property_selected(String p_property);
+
+	TileSetAtlasSourceProxyObject *atlas_source_proxy_object;
+	Label *atlas_source_inspector_label;
+	EditorInspector *atlas_source_inspector;
+
+	// -- Atlas view --
+	HBoxContainer *toolbox;
+	Label *tile_atlas_view_missing_source_label;
+	TileAtlasView *tile_atlas_view;
+
+	// Dragging
+	enum DragType {
+		DRAG_TYPE_NONE = 0,
+		DRAG_TYPE_CREATE_TILES,
+		DRAG_TYPE_CREATE_TILES_USING_RECT,
+		DRAG_TYPE_CREATE_BIG_TILE,
+		DRAG_TYPE_REMOVE_TILES,
+		DRAG_TYPE_REMOVE_TILES_USING_RECT,
+
+		DRAG_TYPE_MOVE_TILE,
+
+		DRAG_TYPE_RECT_SELECT,
+
+		// Warning: keep in this order.
+		DRAG_TYPE_RESIZE_TOP_LEFT,
+		DRAG_TYPE_RESIZE_TOP,
+		DRAG_TYPE_RESIZE_TOP_RIGHT,
+		DRAG_TYPE_RESIZE_RIGHT,
+		DRAG_TYPE_RESIZE_BOTTOM_RIGHT,
+		DRAG_TYPE_RESIZE_BOTTOM,
+		DRAG_TYPE_RESIZE_BOTTOM_LEFT,
+		DRAG_TYPE_RESIZE_LEFT,
+	};
+	DragType drag_type = DRAG_TYPE_NONE;
+	Vector2i drag_start_mouse_pos;
+	Vector2i drag_last_mouse_pos;
+	Vector2i drag_current_tile;
+
+	Rect2i drag_start_tile_shape;
+	Set<Vector2i> drag_modified_tiles;
+	void _end_dragging();
+
+	Map<Vector2i, List<const PropertyInfo *>> _group_properties_per_tiles(const List<PropertyInfo> &r_list, const TileSetAtlasSource *p_atlas);
+
+	// Popup functions.
+	enum MenuOptions {
+		TILE_CREATE,
+		TILE_CREATE_ALTERNATIVE,
+		TILE_DELETE,
+
+		ADVANCED_CLEANUP_TILES_OUTSIDE_TEXTURE,
+		ADVANCED_AUTO_CREATE_TILES,
+		ADVANCED_AUTO_REMOVE_TILES,
+	};
+	Vector2i menu_option_coords;
+	int menu_option_alternative = TileSetAtlasSource::INVALID_TILE_ALTERNATIVE;
+	void _menu_option(int p_option);
+
+	// Tool buttons.
+	Ref<ButtonGroup> tools_button_group;
+	Button *tool_select_button;
+	Button *tool_add_remove_button;
+	Button *tool_add_remove_rect_button;
+	Label *tool_tile_id_label;
+
+	HBoxContainer *tool_settings;
+	VSeparator *tool_settings_vsep;
+	Button *tools_settings_erase_button;
+
+	MenuButton *tool_advanced_menu_buttom;
+
+	// Selection.
+	Set<TileSelection> selection;
+
+	void _set_selection_from_array(Array p_selection);
+	Array _get_selection_as_array();
+
+	// A control on the tile atlas to draw and handle input events.
+	Vector2i hovered_base_tile_coords = TileSetAtlasSource::INVALID_ATLAS_COORDS;
+
+	PopupMenu *base_tile_popup_menu;
+	PopupMenu *empty_base_tile_popup_menu;
+	Ref<Texture2D> resize_handle;
+	Ref<Texture2D> resize_handle_disabled;
+	Control *tile_atlas_control;
+	Control *tile_atlas_control_unscaled;
+	void _tile_atlas_control_draw();
+	void _tile_atlas_control_unscaled_draw();
+	void _tile_atlas_control_mouse_exited();
+	void _tile_atlas_control_gui_input(const Ref<InputEvent> &p_event);
+	void _tile_atlas_view_transform_changed();
+
+	// A control over the alternative tiles.
+	Vector3i hovered_alternative_tile_coords = Vector3i(TileSetAtlasSource::INVALID_ATLAS_COORDS.x, TileSetAtlasSource::INVALID_ATLAS_COORDS.y, TileSetAtlasSource::INVALID_TILE_ALTERNATIVE);
+
+	PopupMenu *alternative_tile_popup_menu;
+	Control *alternative_tiles_control;
+	Control *alternative_tiles_control_unscaled;
+	void _tile_alternatives_control_draw();
+	void _tile_alternatives_control_unscaled_draw();
+	void _tile_alternatives_control_mouse_exited();
+	void _tile_alternatives_control_gui_input(const Ref<InputEvent> &p_event);
+
+	// -- Update functions --
+	void _update_tile_id_label();
+	void _update_source_inspector();
+	void _update_fix_selected_and_hovered_tiles();
+	void _update_tile_inspector();
+	void _update_manage_tile_properties_button();
+	void _update_atlas_view();
+	void _update_toolbar();
+
+	// -- input events --
+	void _unhandled_key_input(const Ref<InputEvent> &p_event);
+
+	// -- Misc --
+	void _auto_create_tiles();
+	void _auto_remove_tiles();
+	AcceptDialog *confirm_auto_create_tiles;
+
+	void _tile_set_atlas_source_changed();
+	void _atlas_source_proxy_object_changed(String p_what);
+
+	void _undo_redo_inspector_callback(Object *p_undo_redo, Object *p_edited, String p_property, Variant p_new_value);
+
+protected:
+	void _notification(int p_what);
+	static void _bind_methods();
+
+public:
+	void edit(Ref<TileSet> p_tile_set, TileSetAtlasSource *p_tile_set_source, int p_source_id);
+	void init_source();
+
+	TileSetAtlasSourceEditor();
+	~TileSetAtlasSourceEditor();
+};
+
+#endif // TILE_SET_ATLAS_SOURCE_EDITOR_H
diff --git a/editor/plugins/tiles/tile_set_editor.cpp b/editor/plugins/tiles/tile_set_editor.cpp
new file mode 100644
index 0000000000..8a5890e9a4
--- /dev/null
+++ b/editor/plugins/tiles/tile_set_editor.cpp
@@ -0,0 +1,520 @@
+/*************************************************************************/
+/*  tile_set_editor.cpp                                                  */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "tile_set_editor.h"
+
+#include "tile_data_editors.h"
+#include "tiles_editor_plugin.h"
+
+#include "editor/editor_scale.h"
+
+#include "scene/gui/box_container.h"
+#include "scene/gui/control.h"
+#include "scene/gui/tab_container.h"
+
+TileSetEditor *TileSetEditor::singleton = nullptr;
+
+void TileSetEditor::drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from) {
+	ERR_FAIL_COND(!tile_set.is_valid());
+
+	if (!can_drop_data_fw(p_point, p_data, p_from)) {
+		return;
+	}
+
+	if (p_from == sources_list) {
+		// Handle dropping a texture in the list of atlas resources.
+		int source_id = -1;
+		int added = 0;
+		Dictionary d = p_data;
+		Vector<String> files = d["files"];
+		for (int i = 0; i < files.size(); i++) {
+			Ref<Texture2D> resource = ResourceLoader::load(files[i]);
+			if (resource.is_valid()) {
+				// Retrieve the id for the next created source.
+				source_id = tile_set->get_next_source_id();
+
+				// Actually create the new source.
+				Ref<TileSetAtlasSource> atlas_source = memnew(TileSetAtlasSource);
+				atlas_source->set_texture(resource);
+				undo_redo->create_action(TTR("Add a new atlas source"));
+				undo_redo->add_do_method(*tile_set, "add_source", atlas_source, source_id);
+				undo_redo->add_do_method(*atlas_source, "set_texture_region_size", tile_set->get_tile_size());
+				undo_redo->add_undo_method(*tile_set, "remove_source", source_id);
+				undo_redo->commit_action();
+				added += 1;
+			}
+		}
+
+		if (added == 1) {
+			tile_set_atlas_source_editor->init_source();
+		}
+
+		// Update the selected source (thus trigerring an update).
+		_update_atlas_sources_list(source_id);
+	}
+}
+
+bool TileSetEditor::can_drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from) const {
+	ERR_FAIL_COND_V(!tile_set.is_valid(), false);
+
+	if (p_from == sources_list) {
+		Dictionary d = p_data;
+
+		if (!d.has("type")) {
+			return false;
+		}
+
+		// Check if we have a Texture2D.
+		if (String(d["type"]) == "files") {
+			Vector<String> files = d["files"];
+
+			if (files.size() == 0) {
+				return false;
+			}
+
+			for (int i = 0; i < files.size(); i++) {
+				String file = files[i];
+				String ftype = EditorFileSystem::get_singleton()->get_file_type(file);
+
+				if (!ClassDB::is_parent_class(ftype, "Texture2D")) {
+					return false;
+				}
+			}
+
+			return true;
+		}
+	}
+	return false;
+}
+
+void TileSetEditor::_update_atlas_sources_list(int force_selected_id) {
+	ERR_FAIL_COND(!tile_set.is_valid());
+
+	// Get the previously selected id.
+	int old_selected = -1;
+	if (sources_list->get_current() >= 0) {
+		int source_id = sources_list->get_item_metadata(sources_list->get_current());
+		if (tile_set->has_source(source_id)) {
+			old_selected = source_id;
+		}
+	}
+
+	int to_select = -1;
+	if (force_selected_id >= 0) {
+		to_select = force_selected_id;
+	} else if (old_selected >= 0) {
+		to_select = old_selected;
+	}
+
+	// Clear the list.
+	sources_list->clear();
+
+	// Update the atlas sources.
+	for (int i = 0; i < tile_set->get_source_count(); i++) {
+		int source_id = tile_set->get_source_id(i);
+
+		// TODO: handle with virtual functions
+		TileSetSource *source = *tile_set->get_source(source_id);
+		TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(source);
+		if (atlas_source) {
+			Ref<Texture2D> texture = atlas_source->get_texture();
+			if (texture.is_valid()) {
+				sources_list->add_item(vformat("%s - (id:%d)", texture->get_path().get_file(), source_id), texture);
+			} else {
+				sources_list->add_item(vformat("No texture atlas source - (id:%d)", source_id), missing_texture_texture);
+			}
+		} else {
+			sources_list->add_item(vformat("Unknown type source - (id:%d)", source_id), missing_texture_texture);
+		}
+		sources_list->set_item_metadata(sources_list->get_item_count() - 1, source_id);
+	}
+
+	// Set again the current selected item if needed.
+	if (to_select >= 0) {
+		for (int i = 0; i < sources_list->get_item_count(); i++) {
+			if ((int)sources_list->get_item_metadata(i) == to_select) {
+				sources_list->set_current(i);
+				if (old_selected != to_select) {
+					sources_list->emit_signal("item_selected", sources_list->get_current());
+				}
+				break;
+			}
+		}
+	}
+
+	// If nothing is selected, select the first entry.
+	if (sources_list->get_current() < 0 && sources_list->get_item_count() > 0) {
+		sources_list->set_current(0);
+		if (old_selected != int(sources_list->get_item_metadata(0))) {
+			sources_list->emit_signal("item_selected", sources_list->get_current());
+		}
+	}
+
+	// If there is no source left, hide all editors and show the label.
+	_source_selected(sources_list->get_current());
+
+	// Synchronize the lists.
+	TilesEditor::get_singleton()->set_atlas_sources_lists_current(sources_list->get_current());
+}
+
+void TileSetEditor::_source_selected(int p_source_index) {
+	ERR_FAIL_COND(!tile_set.is_valid());
+
+	// Update the selected source.
+	sources_delete_button->set_disabled(p_source_index < 0);
+
+	if (p_source_index >= 0) {
+		int source_id = sources_list->get_item_metadata(p_source_index);
+		TileSetAtlasSource *atlas_source = Object::cast_to<TileSetAtlasSource>(*tile_set->get_source(source_id));
+		if (atlas_source) {
+			tile_set_atlas_source_editor->edit(*tile_set, atlas_source, source_id);
+			no_source_selected_label->hide();
+			tile_set_atlas_source_editor->show();
+		} else {
+			no_source_selected_label->show();
+			tile_set_atlas_source_editor->hide();
+		}
+	} else {
+		no_source_selected_label->show();
+		tile_set_atlas_source_editor->hide();
+	}
+}
+
+void TileSetEditor::_source_add_pressed() {
+	ERR_FAIL_COND(!tile_set.is_valid());
+
+	int source_id = tile_set->get_next_source_id();
+
+	Ref<TileSetAtlasSource> atlas_source = memnew(TileSetAtlasSource);
+
+	// Add a new source.
+	undo_redo->create_action(TTR("Add atlas source"));
+	undo_redo->add_do_method(*tile_set, "add_source", atlas_source, source_id);
+	undo_redo->add_do_method(*atlas_source, "set_texture_region_size", tile_set->get_tile_size());
+	undo_redo->add_undo_method(*tile_set, "remove_source", source_id);
+	undo_redo->commit_action();
+
+	_update_atlas_sources_list(source_id);
+}
+
+void TileSetEditor::_source_delete_pressed() {
+	ERR_FAIL_COND(!tile_set.is_valid());
+
+	// Update the selected source.
+	int to_delete = sources_list->get_item_metadata(sources_list->get_current());
+
+	Ref<TileSetSource> source = tile_set->get_source(to_delete);
+
+	// Remove the source.
+	undo_redo->create_action(TTR("Remove source"));
+	undo_redo->add_do_method(*tile_set, "remove_source", to_delete);
+	undo_redo->add_undo_method(*tile_set, "add_source", source, to_delete);
+	undo_redo->commit_action();
+
+	_update_atlas_sources_list();
+}
+
+void TileSetEditor::_notification(int p_what) {
+	switch (p_what) {
+		case NOTIFICATION_ENTER_TREE:
+		case NOTIFICATION_THEME_CHANGED:
+			sources_delete_button->set_icon(get_theme_icon("Remove", "EditorIcons"));
+			sources_add_button->set_icon(get_theme_icon("Add", "EditorIcons"));
+			missing_texture_texture = get_theme_icon("TileSet", "EditorIcons");
+			break;
+		case NOTIFICATION_INTERNAL_PROCESS:
+			if (tile_set_changed_needs_update) {
+				_update_atlas_sources_list();
+				tile_set_changed_needs_update = false;
+			}
+			break;
+		default:
+			break;
+	}
+}
+
+void TileSetEditor::_tile_set_changed() {
+	tile_set_changed_needs_update = true;
+}
+
+void TileSetEditor::_undo_redo_inspector_callback(Object *p_undo_redo, Object *p_edited, String p_property, Variant p_new_value) {
+	UndoRedo *undo_redo = Object::cast_to<UndoRedo>(p_undo_redo);
+	ERR_FAIL_COND(!undo_redo);
+
+#define ADD_UNDO(obj, property) undo_redo->add_undo_property(obj, property, tile_data->get(property));
+	TileSet *tile_set = Object::cast_to<TileSet>(p_edited);
+	if (tile_set) {
+		Vector<String> components = p_property.split("/", true, 3);
+		for (int i = 0; i < tile_set->get_source_count(); i++) {
+			int source_id = tile_set->get_source_id(i);
+
+			Ref<TileSetAtlasSource> tas = tile_set->get_source(source_id);
+			if (tas.is_valid()) {
+				for (int j = 0; j < tas->get_tiles_count(); j++) {
+					Vector2i tile_id = tas->get_tile_id(j);
+					for (int k = 0; k < tas->get_alternative_tiles_count(tile_id); k++) {
+						int alternative_id = tas->get_alternative_tile_id(tile_id, k);
+						TileData *tile_data = Object::cast_to<TileData>(tas->get_tile_data(tile_id, alternative_id));
+						ERR_FAIL_COND(!tile_data);
+
+						if (p_property == "occlusion_layers_count") {
+							int new_layer_count = p_new_value;
+							int old_layer_count = tile_set->get_occlusion_layers_count();
+							if (new_layer_count < old_layer_count) {
+								for (int occclusion_layer_index = new_layer_count - 1; occclusion_layer_index < old_layer_count; occclusion_layer_index++) {
+									ADD_UNDO(tile_data, vformat("occlusion_layer_%d/polygon", occclusion_layer_index));
+								}
+							}
+						} else if (p_property == "physics_layers_count") {
+							int new_layer_count = p_new_value;
+							int old_layer_count = tile_set->get_physics_layers_count();
+							if (new_layer_count < old_layer_count) {
+								for (int physics_layer_index = new_layer_count - 1; physics_layer_index < old_layer_count; physics_layer_index++) {
+									ADD_UNDO(tile_data, vformat("physics_layer_%d/shapes_count", physics_layer_index));
+									for (int shape_index = 0; shape_index < tile_data->get_collision_shapes_count(physics_layer_index); shape_index++) {
+										ADD_UNDO(tile_data, vformat("physics_layer_%d/shape_%d/shape", physics_layer_index, shape_index));
+										ADD_UNDO(tile_data, vformat("physics_layer_%d/shape_%d/one_way", physics_layer_index, shape_index));
+										ADD_UNDO(tile_data, vformat("physics_layer_%d/shape_%d/one_way_margin", physics_layer_index, shape_index));
+									}
+								}
+							}
+						} else if ((p_property == "terrains_sets_count" && tile_data->get_terrain_set() >= (int)p_new_value) ||
+								   (components.size() == 2 && components[0].begins_with("terrain_set_") && components[0].trim_prefix("terrain_set_").is_valid_integer() && components[1] == "mode") ||
+								   (components.size() == 2 && components[0].begins_with("terrain_set_") && components[0].trim_prefix("terrain_set_").is_valid_integer() && components[1] == "terrains_count" && tile_data->get_terrain_set() == components[0].trim_prefix("terrain_set_").to_int() && (int)p_new_value < tile_set->get_terrains_count(tile_data->get_terrain_set()))) {
+							ADD_UNDO(tile_data, "terrain_set");
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_RIGHT_SIDE)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/right_side");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_RIGHT_CORNER)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/right_corner");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_SIDE)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/bottom_right_side");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_BOTTOM_RIGHT_CORNER)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/bottom_right_corner");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_BOTTOM_SIDE)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/bottom_side");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_BOTTOM_CORNER)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/bottom_corner");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_SIDE)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/bottom_left_side");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_BOTTOM_LEFT_CORNER)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/bottom_left_corner");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_LEFT_SIDE)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/left_side");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_LEFT_CORNER)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/left_corner");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_TOP_LEFT_SIDE)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/top_left_side");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_TOP_LEFT_CORNER)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/top_left_corner");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_TOP_SIDE)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/top_side");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_TOP_CORNER)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/top_corner");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_TOP_RIGHT_SIDE)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/top_right_side");
+							}
+							if (tile_data->is_valid_peering_bit_terrain(TileSet::CELL_NEIGHBOR_TOP_RIGHT_CORNER)) {
+								ADD_UNDO(tile_data, "terrains_peering_bit/top_right_corner");
+							}
+						} else if (p_property == "navigation_layers_count") {
+							int new_layer_count = p_new_value;
+							int old_layer_count = tile_set->get_navigation_layers_count();
+							if (new_layer_count < old_layer_count) {
+								for (int navigation_layer_index = new_layer_count - 1; navigation_layer_index < old_layer_count; navigation_layer_index++) {
+									ADD_UNDO(tile_data, vformat("navigation_layer_%d/polygon", navigation_layer_index));
+								}
+							}
+						} else if (p_property == "custom_data_layers_count") {
+							int new_layer_count = p_new_value;
+							int old_layer_count = tile_set->get_custom_data_layers_count();
+							if (new_layer_count < old_layer_count) {
+								for (int custom_data_layer_index = new_layer_count - 1; custom_data_layer_index < old_layer_count; custom_data_layer_index++) {
+									ADD_UNDO(tile_data, vformat("custom_data_%d", custom_data_layer_index));
+								}
+							}
+						} else if (components.size() == 2 && components[0].begins_with("custom_data_layer_") && components[0].trim_prefix("custom_data_layer_").is_valid_integer() && components[1] == "type") {
+							int custom_data_layer = components[0].trim_prefix("custom_data_layer_").is_valid_integer();
+							ADD_UNDO(tile_data, vformat("custom_data_%d", custom_data_layer));
+						}
+					}
+				}
+			}
+		}
+	}
+#undef ADD_UNDO
+}
+
+void TileSetEditor::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("can_drop_data_fw"), &TileSetEditor::can_drop_data_fw);
+	ClassDB::bind_method(D_METHOD("drop_data_fw"), &TileSetEditor::drop_data_fw);
+}
+
+TileDataEditor *TileSetEditor::get_tile_data_editor(String p_property) {
+	Vector<String> components = String(p_property).split("/", true);
+
+	if (p_property == "z_index") {
+		return tile_data_integer_editor;
+	} else if (p_property == "probability") {
+		return tile_data_float_editor;
+	} else if (p_property == "y_sort_origin") {
+		return tile_data_position_editor;
+	} else if (p_property == "texture_offset") {
+		return tile_data_texture_offset_editor;
+	} else if (components.size() >= 1 && components[0].begins_with("occlusion_layer_")) {
+		return tile_data_occlusion_shape_editor;
+	} else if (components.size() >= 1 && components[0].begins_with("physics_layer_")) {
+		return tile_data_collision_shape_editor;
+	} else if (p_property == "mode" || p_property == "terrain" || (components.size() >= 1 && components[0] == "terrains_peering_bit")) {
+		return tile_data_terrains_editor;
+	} else if (components.size() >= 1 && components[0].begins_with("navigation_layer_")) {
+		return tile_data_navigation_polygon_editor;
+	}
+
+	return nullptr;
+}
+
+void TileSetEditor::edit(Ref<TileSet> p_tile_set) {
+	if (p_tile_set == tile_set) {
+		return;
+	}
+
+	// Remove listener.
+	if (tile_set.is_valid()) {
+		tile_set->disconnect("changed", callable_mp(this, &TileSetEditor::_tile_set_changed));
+	}
+
+	// Change the edited object.
+	tile_set = p_tile_set;
+
+	// Add the listener again.
+	if (tile_set.is_valid()) {
+		tile_set->connect("changed", callable_mp(this, &TileSetEditor::_tile_set_changed));
+		_update_atlas_sources_list();
+	}
+
+	tile_set_atlas_source_editor->hide();
+	no_source_selected_label->show();
+}
+
+TileSetEditor::TileSetEditor() {
+	singleton = this;
+
+	set_process_internal(true);
+
+	// Split container.
+	HSplitContainer *split_container = memnew(HSplitContainer);
+	split_container->set_name(TTR("Tiles"));
+	split_container->set_h_size_flags(SIZE_EXPAND_FILL);
+	split_container->set_v_size_flags(SIZE_EXPAND_FILL);
+	add_child(split_container);
+
+	// Sources list.
+	VBoxContainer *split_container_left_side = memnew(VBoxContainer);
+	split_container_left_side->set_h_size_flags(SIZE_EXPAND_FILL);
+	split_container_left_side->set_v_size_flags(SIZE_EXPAND_FILL);
+	split_container_left_side->set_stretch_ratio(0.25);
+	split_container_left_side->set_custom_minimum_size(Size2i(70, 0) * EDSCALE);
+	split_container->add_child(split_container_left_side);
+
+	sources_list = memnew(ItemList);
+	sources_list->set_fixed_icon_size(Size2i(60, 60) * EDSCALE);
+	sources_list->set_h_size_flags(SIZE_EXPAND_FILL);
+	sources_list->set_v_size_flags(SIZE_EXPAND_FILL);
+	sources_list->connect("item_selected", callable_mp(this, &TileSetEditor::_source_selected));
+	sources_list->connect("item_selected", callable_mp(TilesEditor::get_singleton(), &TilesEditor::set_atlas_sources_lists_current));
+	sources_list->connect("visibility_changed", callable_mp(TilesEditor::get_singleton(), &TilesEditor::synchronize_atlas_sources_list), varray(sources_list));
+	sources_list->set_drag_forwarding(this);
+	split_container_left_side->add_child(sources_list);
+
+	HBoxContainer *sources_bottom_actions = memnew(HBoxContainer);
+	sources_bottom_actions->set_alignment(HBoxContainer::ALIGN_END);
+	split_container_left_side->add_child(sources_bottom_actions);
+
+	sources_delete_button = memnew(Button);
+	sources_delete_button->set_flat(true);
+	sources_delete_button->set_disabled(true);
+	sources_delete_button->connect("pressed", callable_mp(this, &TileSetEditor::_source_delete_pressed));
+	sources_bottom_actions->add_child(sources_delete_button);
+
+	sources_add_button = memnew(Button);
+	sources_add_button->set_flat(true);
+	sources_add_button->connect("pressed", callable_mp(this, &TileSetEditor::_source_add_pressed));
+	sources_bottom_actions->add_child(sources_add_button);
+
+	// No source selected.
+	no_source_selected_label = memnew(Label);
+	no_source_selected_label->set_text(TTR("No TileSet source selected. Select or create a TileSet source."));
+	no_source_selected_label->set_h_size_flags(SIZE_EXPAND_FILL);
+	no_source_selected_label->set_v_size_flags(SIZE_EXPAND_FILL);
+	no_source_selected_label->set_align(Label::ALIGN_CENTER);
+	no_source_selected_label->set_valign(Label::VALIGN_CENTER);
+	split_container->add_child(no_source_selected_label);
+
+	// Atlases editor.
+	tile_set_atlas_source_editor = memnew(TileSetAtlasSourceEditor);
+	tile_set_atlas_source_editor->set_h_size_flags(SIZE_EXPAND_FILL);
+	tile_set_atlas_source_editor->set_v_size_flags(SIZE_EXPAND_FILL);
+	tile_set_atlas_source_editor->connect("source_id_changed", callable_mp(this, &TileSetEditor::_update_atlas_sources_list));
+	split_container->add_child(tile_set_atlas_source_editor);
+	tile_set_atlas_source_editor->hide();
+
+	// Registers UndoRedo inspector callback.
+	EditorNode::get_singleton()->get_editor_data().add_undo_redo_inspector_hook_callback(callable_mp(this, &TileSetEditor::_undo_redo_inspector_callback));
+}
+
+TileSetEditor::~TileSetEditor() {
+	if (tile_set.is_valid()) {
+		tile_set->disconnect("changed", callable_mp(this, &TileSetEditor::_tile_set_changed));
+	}
+
+	// Delete tile data editors.
+	memdelete(tile_data_texture_offset_editor);
+	memdelete(tile_data_position_editor);
+	memdelete(tile_data_integer_editor);
+	memdelete(tile_data_float_editor);
+	memdelete(tile_data_occlusion_shape_editor);
+	memdelete(tile_data_collision_shape_editor);
+	memdelete(tile_data_terrains_editor);
+	memdelete(tile_data_navigation_polygon_editor);
+}
diff --git a/editor/plugins/tiles/tile_set_editor.h b/editor/plugins/tiles/tile_set_editor.h
new file mode 100644
index 0000000000..c4aebb40a2
--- /dev/null
+++ b/editor/plugins/tiles/tile_set_editor.h
@@ -0,0 +1,94 @@
+/*************************************************************************/
+/*  tile_set_editor.h                                                    */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef TILE_SET_EDITOR_H
+#define TILE_SET_EDITOR_H
+
+#include "scene/gui/box_container.h"
+#include "scene/resources/tile_set.h"
+#include "tile_data_editors.h"
+#include "tile_set_atlas_source_editor.h"
+
+class TileSetEditor : public VBoxContainer {
+	GDCLASS(TileSetEditor, VBoxContainer);
+
+	static TileSetEditor *singleton;
+
+private:
+	Ref<TileSet> tile_set;
+	bool tile_set_changed_needs_update = false;
+
+	Label *no_source_selected_label;
+	TileSetAtlasSourceEditor *tile_set_atlas_source_editor;
+
+	UndoRedo *undo_redo = EditorNode::get_undo_redo();
+
+	void _update_atlas_sources_list(int force_selected_id = -1);
+
+	// List of tile data editors.
+	TileDataTextureOffsetEditor *tile_data_texture_offset_editor = memnew(TileDataTextureOffsetEditor);
+	TileDataPositionEditor *tile_data_position_editor = memnew(TileDataPositionEditor);
+	TileDataIntegerEditor *tile_data_integer_editor = memnew(TileDataIntegerEditor);
+	TileDataFloatEditor *tile_data_float_editor = memnew(TileDataFloatEditor);
+	TileDataOcclusionShapeEditor *tile_data_occlusion_shape_editor = memnew(TileDataOcclusionShapeEditor);
+	TileDataCollisionShapeEditor *tile_data_collision_shape_editor = memnew(TileDataCollisionShapeEditor);
+	TileDataTerrainsEditor *tile_data_terrains_editor = memnew(TileDataTerrainsEditor);
+	TileDataNavigationPolygonEditor *tile_data_navigation_polygon_editor = memnew(TileDataNavigationPolygonEditor);
+
+	// -- Sources management --
+	Button *sources_delete_button;
+	Button *sources_add_button;
+	ItemList *sources_list;
+	Ref<Texture2D> missing_texture_texture;
+	void _source_selected(int p_source_index);
+	void _source_add_pressed();
+	void _source_delete_pressed();
+
+	void _tile_set_changed();
+
+	void _undo_redo_inspector_callback(Object *p_undo_redo, Object *p_edited, String p_property, Variant p_new_value);
+
+protected:
+	void _notification(int p_what);
+	static void _bind_methods();
+
+public:
+	_FORCE_INLINE_ static TileSetEditor *get_singleton() { return singleton; }
+
+	TileDataEditor *get_tile_data_editor(String property);
+	void edit(Ref<TileSet> p_tile_set);
+	void drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from);
+	bool can_drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from) const;
+
+	TileSetEditor();
+	~TileSetEditor();
+};
+
+#endif // TILE_SET_EDITOR_PLUGIN_H
diff --git a/editor/plugins/tiles/tiles_editor_plugin.cpp b/editor/plugins/tiles/tiles_editor_plugin.cpp
new file mode 100644
index 0000000000..971ff15073
--- /dev/null
+++ b/editor/plugins/tiles/tiles_editor_plugin.cpp
@@ -0,0 +1,276 @@
+/*************************************************************************/
+/*  tiles_editor_plugin.cpp                                              */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "tiles_editor_plugin.h"
+
+#include "editor/editor_node.h"
+#include "editor/editor_scale.h"
+#include "editor/plugins/canvas_item_editor_plugin.h"
+
+#include "scene/2d/tile_map.h"
+#include "scene/resources/tile_set.h"
+
+#include "scene/gui/box_container.h"
+#include "scene/gui/button.h"
+#include "scene/gui/control.h"
+#include "scene/gui/separator.h"
+
+#include "tile_set_editor.h"
+
+TilesEditor *TilesEditor::singleton = nullptr;
+
+void TilesEditor::_notification(int p_what) {
+	switch (p_what) {
+		case NOTIFICATION_ENTER_TREE:
+		case NOTIFICATION_THEME_CHANGED: {
+			tileset_tilemap_switch_button->set_icon(get_theme_icon("TileSet", "EditorIcons"));
+		} break;
+		case NOTIFICATION_INTERNAL_PROCESS: {
+			if (tile_map_changed_needs_update) {
+				TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+				if (tile_map) {
+					tile_set = tile_map->get_tileset();
+				}
+				_update_switch_button();
+				_update_editors();
+			}
+		} break;
+	}
+}
+
+void TilesEditor::_tile_map_changed() {
+	tile_map_changed_needs_update = true;
+}
+
+void TilesEditor::_update_switch_button() {
+	// Force the buttons status if needed.
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (tile_map && !tile_set.is_valid()) {
+		tileset_tilemap_switch_button->set_pressed(false);
+	} else if (!tile_map && tile_set.is_valid()) {
+		tileset_tilemap_switch_button->set_pressed(true);
+	}
+}
+
+void TilesEditor::_update_editors() {
+	// Set editors visibility.
+	tilemap_toolbar->set_visible(!tileset_tilemap_switch_button->is_pressed());
+	tilemap_editor->set_visible(!tileset_tilemap_switch_button->is_pressed());
+	tileset_editor->set_visible(tileset_tilemap_switch_button->is_pressed());
+
+	// Enable/disable the switch button.
+	if (!tileset_tilemap_switch_button->is_pressed()) {
+		if (!tile_set.is_valid()) {
+			tileset_tilemap_switch_button->set_disabled(true);
+			tileset_tilemap_switch_button->set_tooltip(TTR("This TileMap has no assigned TileSet, assign a TileSet to this TileMap to edit it."));
+		} else {
+			tileset_tilemap_switch_button->set_disabled(false);
+			tileset_tilemap_switch_button->set_tooltip(TTR("Switch between TileSet/TileMap editor."));
+		}
+	} else {
+		TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+		if (!tile_map) {
+			tileset_tilemap_switch_button->set_disabled(true);
+			tileset_tilemap_switch_button->set_tooltip(TTR("You are editing a TileSet resource. Select a TileMap node to paint."));
+		} else {
+			tileset_tilemap_switch_button->set_disabled(false);
+			tileset_tilemap_switch_button->set_tooltip(TTR("Switch between TileSet/TileMap editor."));
+		}
+	}
+
+	// If tile_map is not edited, we change the edited only if we are not editing a tile_set.
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (tile_map) {
+		tilemap_editor->edit(tile_map);
+	} else {
+		tilemap_editor->edit(nullptr);
+	}
+	tileset_editor->edit(tile_set);
+
+	// Update the viewport
+	CanvasItemEditor::get_singleton()->update_viewport();
+}
+
+void TilesEditor::set_atlas_sources_lists_current(int p_current) {
+	atlas_sources_lists_current = p_current;
+}
+
+void TilesEditor::synchronize_atlas_sources_list(Object *p_current) {
+	ItemList *item_list = Object::cast_to<ItemList>(p_current);
+	ERR_FAIL_COND(!item_list);
+
+	if (item_list->is_visible_in_tree()) {
+		if (atlas_sources_lists_current < 0 || atlas_sources_lists_current >= item_list->get_item_count()) {
+			item_list->deselect_all();
+		} else {
+			item_list->set_current(atlas_sources_lists_current);
+			item_list->emit_signal("item_selected", atlas_sources_lists_current);
+		}
+	}
+}
+
+void TilesEditor::set_atlas_view_transform(float p_zoom, Vector2 p_scroll) {
+	atlas_view_zoom = p_zoom;
+	atlas_view_scroll = p_scroll;
+}
+
+void TilesEditor::synchronize_atlas_view(Object *p_current) {
+	TileAtlasView *tile_atlas_view = Object::cast_to<TileAtlasView>(p_current);
+	ERR_FAIL_COND(!tile_atlas_view);
+
+	if (tile_atlas_view->is_visible_in_tree()) {
+		tile_atlas_view->set_transform(atlas_view_zoom, Vector2(atlas_view_scroll.x, atlas_view_scroll.y));
+	}
+}
+
+void TilesEditor::edit(Object *p_object) {
+	// Disconnect to changes.
+	TileMap *tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+	if (tile_map) {
+		tile_map->disconnect("changed", callable_mp(this, &TilesEditor::_tile_map_changed));
+	}
+
+	// Update edited objects.
+	tile_set = Ref<TileSet>();
+	if (p_object) {
+		if (p_object->is_class("TileMap")) {
+			tile_map_id = p_object->get_instance_id();
+			tile_map = Object::cast_to<TileMap>(ObjectDB::get_instance(tile_map_id));
+			tile_set = tile_map->get_tileset();
+		} else if (p_object->is_class("TileSet")) {
+			tile_set = Ref<TileSet>(p_object);
+			if (tile_map) {
+				if (tile_map->get_tileset() != tile_set) {
+					tile_map = nullptr;
+				}
+			}
+		}
+
+		// Update pressed status button.
+		if (p_object->is_class("TileMap")) {
+			tileset_tilemap_switch_button->set_pressed(false);
+		} else if (p_object->is_class("TileSet")) {
+			tileset_tilemap_switch_button->set_pressed(true);
+		}
+	}
+
+	// Update the editors.
+	_update_switch_button();
+	_update_editors();
+
+	// Add change listener.
+	if (tile_map) {
+		tile_map->connect("changed", callable_mp(this, &TilesEditor::_tile_map_changed));
+	}
+}
+
+void TilesEditor::_bind_methods() {
+}
+
+TilesEditor::TilesEditor(EditorNode *p_editor) {
+	set_process_internal(true);
+
+	// Update the singleton.
+	singleton = this;
+
+	// Toolbar.
+	HBoxContainer *toolbar = memnew(HBoxContainer);
+	add_child(toolbar);
+
+	// Switch button.
+	tileset_tilemap_switch_button = memnew(Button);
+	tileset_tilemap_switch_button->set_flat(true);
+	tileset_tilemap_switch_button->set_toggle_mode(true);
+	tileset_tilemap_switch_button->connect("toggled", callable_mp(this, &TilesEditor::_update_editors).unbind(1));
+	toolbar->add_child(tileset_tilemap_switch_button);
+
+	// Tilemap editor.
+	tilemap_editor = memnew(TileMapEditor);
+	tilemap_editor->set_h_size_flags(SIZE_EXPAND_FILL);
+	tilemap_editor->set_v_size_flags(SIZE_EXPAND_FILL);
+	tilemap_editor->hide();
+	add_child(tilemap_editor);
+
+	tilemap_toolbar = tilemap_editor->get_toolbar();
+	toolbar->add_child(tilemap_toolbar);
+
+	// Tileset editor.
+	tileset_editor = memnew(TileSetEditor);
+	tileset_editor->set_h_size_flags(SIZE_EXPAND_FILL);
+	tileset_editor->set_v_size_flags(SIZE_EXPAND_FILL);
+	tileset_editor->hide();
+	add_child(tileset_editor);
+
+	// Initialization.
+	_update_switch_button();
+	_update_editors();
+}
+
+TilesEditor::~TilesEditor() {
+}
+
+///////////////////////////////////////////////////////////////
+
+void TilesEditorPlugin::_notification(int p_what) {
+}
+
+void TilesEditorPlugin::make_visible(bool p_visible) {
+	if (p_visible) {
+		tiles_editor_button->show();
+		editor_node->make_bottom_panel_item_visible(tiles_editor);
+		//get_tree()->connect_compat("idle_frame", tileset_editor, "_on_workspace_process");
+	} else {
+		editor_node->hide_bottom_panel();
+		tiles_editor_button->hide();
+		//get_tree()->disconnect_compat("idle_frame", tileset_editor, "_on_workspace_process");
+	}
+}
+
+void TilesEditorPlugin::edit(Object *p_object) {
+	tiles_editor->edit(p_object);
+}
+
+bool TilesEditorPlugin::handles(Object *p_object) const {
+	return p_object->is_class("TileMap") || p_object->is_class("TileSet");
+}
+
+TilesEditorPlugin::TilesEditorPlugin(EditorNode *p_node) {
+	editor_node = p_node;
+
+	tiles_editor = memnew(TilesEditor(p_node));
+	tiles_editor->set_custom_minimum_size(Size2(0, 200) * EDSCALE);
+	tiles_editor->hide();
+
+	tiles_editor_button = p_node->add_bottom_panel_item(TTR("Tiles"), tiles_editor);
+	tiles_editor_button->hide();
+}
+
+TilesEditorPlugin::~TilesEditorPlugin() {
+}
diff --git a/editor/plugins/tiles/tiles_editor_plugin.h b/editor/plugins/tiles/tiles_editor_plugin.h
new file mode 100644
index 0000000000..6cc6f51598
--- /dev/null
+++ b/editor/plugins/tiles/tiles_editor_plugin.h
@@ -0,0 +1,114 @@
+/*************************************************************************/
+/*  tiles_editor_plugin.h                                                */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef TILES_EDITOR_PLUGIN_H
+#define TILES_EDITOR_PLUGIN_H
+
+#include "editor/editor_plugin.h"
+#include "scene/gui/box_container.h"
+
+#include "tile_atlas_view.h"
+#include "tile_map_editor.h"
+#include "tile_set_editor.h"
+
+class TilesEditor : public VBoxContainer {
+	GDCLASS(TilesEditor, VBoxContainer);
+
+	static TilesEditor *singleton;
+
+private:
+	bool tile_map_changed_needs_update = false;
+	ObjectID tile_map_id;
+	Ref<TileSet> tile_set;
+
+	Button *tileset_tilemap_switch_button;
+
+	Control *tilemap_toolbar;
+	TileMapEditor *tilemap_editor;
+
+	TileSetEditor *tileset_editor;
+
+	void _update_switch_button();
+	void _update_editors();
+
+	// For synchronization.
+	int atlas_sources_lists_current = 0;
+	float atlas_view_zoom = 1.0;
+	Vector2 atlas_view_scroll = Vector2();
+
+	void _tile_map_changed();
+
+protected:
+	void _notification(int p_what);
+	static void _bind_methods();
+
+public:
+	_FORCE_INLINE_ static TilesEditor *get_singleton() { return singleton; }
+
+	bool forward_canvas_gui_input(const Ref<InputEvent> &p_event) { return tilemap_editor->forward_canvas_gui_input(p_event); }
+	void forward_canvas_draw_over_viewport(Control *p_overlay) { tilemap_editor->forward_canvas_draw_over_viewport(p_overlay); }
+
+	// To synchronize the atlas sources lists.
+	void set_atlas_sources_lists_current(int p_current);
+	void synchronize_atlas_sources_list(Object *p_current);
+
+	void set_atlas_view_transform(float p_zoom, Vector2 p_scroll);
+	void synchronize_atlas_view(Object *p_current);
+
+	void edit(Object *p_object);
+
+	TilesEditor(EditorNode *p_editor);
+	~TilesEditor();
+};
+
+class TilesEditorPlugin : public EditorPlugin {
+	GDCLASS(TilesEditorPlugin, EditorPlugin);
+
+private:
+	EditorNode *editor_node;
+	TilesEditor *tiles_editor;
+	Button *tiles_editor_button;
+
+protected:
+	void _notification(int p_what);
+
+public:
+	virtual bool forward_canvas_gui_input(const Ref<InputEvent> &p_event) override { return tiles_editor->forward_canvas_gui_input(p_event); }
+	virtual void forward_canvas_draw_over_viewport(Control *p_overlay) override { tiles_editor->forward_canvas_draw_over_viewport(p_overlay); }
+
+	virtual void edit(Object *p_object) override;
+	virtual bool handles(Object *p_object) const override;
+	virtual void make_visible(bool p_visible) override;
+
+	TilesEditorPlugin(EditorNode *p_node);
+	~TilesEditorPlugin();
+};
+
+#endif // TILES_EDITOR_PLUGIN_H