Merge pull request #58687 from YeldhamDev/the_beast_has_been_slain

4 files changed, 421 insertions, 788 deletions

diff --git a/scene/gui/tab_bar.cpp b/scene/gui/tab_bar.cpp
index ce60da762f..0e088a44e5 100644
--- a/scene/gui/tab_bar.cpp
+++ b/scene/gui/tab_bar.cpp
@@ -552,10 +552,6 @@ void TabBar::set_current_tab(int p_current) {
 		emit_signal(SNAME("tab_selected"), current);
 		return;
 	}
-	// Triggered by dragging a tab from another TabBar to the selected index, to ensure that tab_changed is emitted.
-	if (previous == -1) {
-		previous = current;
-	}
 
 	emit_signal(SNAME("tab_selected"), current);
 
@@ -954,9 +950,17 @@ void TabBar::add_tab(const String &p_str, const Ref<Texture2D> &p_icon) {
 	}
 	update();
 	update_minimum_size();
+
+	if (tabs.size() == 1 && is_inside_tree()) {
+		emit_signal(SNAME("tab_changed"), 0);
+	}
 }
 
 void TabBar::clear_tabs() {
+	if (tabs.is_empty()) {
+		return;
+	}
+
 	tabs.clear();
 	offset = 0;
 	max_drawn_tab = 0;
@@ -971,14 +975,16 @@ void TabBar::clear_tabs() {
 void TabBar::remove_tab(int p_idx) {
 	ERR_FAIL_INDEX(p_idx, tabs.size());
 	tabs.remove_at(p_idx);
-	if (current >= p_idx) {
+
+	bool is_tab_changing = current == p_idx && !tabs.is_empty();
+
+	if (current >= p_idx && current > 0) {
 		current--;
 	}
 
-	if (current < 0) {
+	if (tabs.is_empty()) {
 		offset = 0;
 		max_drawn_tab = 0;
-		current = 0;
 		previous = 0;
 	} else {
 		offset = MIN(offset, tabs.size() - 1);
@@ -986,7 +992,7 @@ void TabBar::remove_tab(int p_idx) {
 
 		_update_cache();
 		_ensure_no_over_offset();
-		if (scroll_to_selected && !tabs.is_empty()) {
+		if (scroll_to_selected) {
 			ensure_tab_visible(current);
 		}
 	}
@@ -994,15 +1000,18 @@ void TabBar::remove_tab(int p_idx) {
 	update();
 	update_minimum_size();
 	notify_property_list_changed();
+
+	if (is_tab_changing && is_inside_tree()) {
+		emit_signal(SNAME("tab_changed"), current);
+	}
 }
 
 Variant TabBar::get_drag_data(const Point2 &p_point) {
 	if (!drag_to_rearrange_enabled) {
-		return Variant();
+		return Control::get_drag_data(p_point); // Allow stuff like TabContainer to override it.
 	}
 
 	int tab_over = get_tab_idx_at_point(p_point);
-
 	if (tab_over < 0) {
 		return Variant();
 	}
@@ -1025,12 +1034,13 @@ Variant TabBar::get_drag_data(const Point2 &p_point) {
 	drag_data["type"] = "tab_element";
 	drag_data["tab_element"] = tab_over;
 	drag_data["from_path"] = get_path();
+
 	return drag_data;
 }
 
 bool TabBar::can_drop_data(const Point2 &p_point, const Variant &p_data) const {
 	if (!drag_to_rearrange_enabled) {
-		return false;
+		return Control::can_drop_data(p_point, p_data); // Allow stuff like TabContainer to override it.
 	}
 
 	Dictionary d = p_data;
@@ -1052,16 +1062,16 @@ bool TabBar::can_drop_data(const Point2 &p_point, const Variant &p_data) const {
 			}
 		}
 	}
+
 	return false;
 }
 
 void TabBar::drop_data(const Point2 &p_point, const Variant &p_data) {
 	if (!drag_to_rearrange_enabled) {
+		Control::drop_data(p_point, p_data); // Allow stuff like TabContainer to override it.
 		return;
 	}
 
-	int hover_now = get_tab_idx_at_point(p_point);
-
 	Dictionary d = p_data;
 	if (!d.has("type")) {
 		return;
@@ -1069,6 +1079,7 @@ void TabBar::drop_data(const Point2 &p_point, const Variant &p_data) {
 
 	if (String(d["type"]) == "tab_element") {
 		int tab_from_id = d["tab_element"];
+		int hover_now = get_tab_idx_at_point(p_point);
 		NodePath from_path = d["from_path"];
 		NodePath to_path = get_path();
 
@@ -1096,15 +1107,25 @@ void TabBar::drop_data(const Point2 &p_point, const Variant &p_data) {
 					hover_now = get_tab_count();
 				}
 
-				// Workaround to ensure that tab_changed is emitted.
-				if (current == hover_now) {
-					current = -1;
+				from_tabs->remove_tab(tab_from_id);
+				tabs.insert(hover_now, moving_tab);
+
+				if (tabs.size() > 1) {
+					if (current >= hover_now) {
+						current++;
+					}
+					if (previous >= hover_now) {
+						previous++;
+					}
 				}
 
-				tabs.insert(hover_now, moving_tab);
-				from_tabs->remove_tab(tab_from_id);
 				set_current_tab(hover_now);
 				update_minimum_size();
+
+				if (tabs.size() == 1) {
+					emit_signal(SNAME("tab_selected"), 0);
+					emit_signal(SNAME("tab_changed"), 0);
+				}
 			}
 		}
 	}
@@ -1157,17 +1178,33 @@ bool TabBar::get_clip_tabs() const {
 	return clip_tabs;
 }
 
-void TabBar::move_tab(int from, int to) {
-	if (from == to) {
+void TabBar::move_tab(int p_from, int p_to) {
+	if (p_from == p_to) {
 		return;
 	}
 
-	ERR_FAIL_INDEX(from, tabs.size());
-	ERR_FAIL_INDEX(to, tabs.size());
+	ERR_FAIL_INDEX(p_from, tabs.size());
+	ERR_FAIL_INDEX(p_to, tabs.size());
+
+	Tab tab_from = tabs[p_from];
+	tabs.remove_at(p_from);
+	tabs.insert(p_to, tab_from);
 
-	Tab tab_from = tabs[from];
-	tabs.remove_at(from);
-	tabs.insert(to, tab_from);
+	if (current == p_from) {
+		current = p_to;
+	} else if (current > p_from && current <= p_to) {
+		current--;
+	} else if (current < p_from && current >= p_to) {
+		current++;
+	}
+
+	if (previous == p_from) {
+		previous = p_to;
+	} else if (previous > p_from && previous >= p_to) {
+		previous--;
+	} else if (previous < p_from && previous <= p_to) {
+		previous++;
+	}
 
 	_update_cache();
 	_ensure_no_over_offset();
@@ -1466,6 +1503,7 @@ void TabBar::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("is_tab_hidden", "tab_idx"), &TabBar::is_tab_hidden);
 	ClassDB::bind_method(D_METHOD("remove_tab", "tab_idx"), &TabBar::remove_tab);
 	ClassDB::bind_method(D_METHOD("add_tab", "title", "icon"), &TabBar::add_tab, DEFVAL(""), DEFVAL(Ref<Texture2D>()));
+	ClassDB::bind_method(D_METHOD("get_tab_idx_at_point", "point"), &TabBar::get_tab_idx_at_point);
 	ClassDB::bind_method(D_METHOD("set_tab_alignment", "alignment"), &TabBar::set_tab_alignment);
 	ClassDB::bind_method(D_METHOD("get_tab_alignment"), &TabBar::get_tab_alignment);
 	ClassDB::bind_method(D_METHOD("set_clip_tabs", "clip_tabs"), &TabBar::set_clip_tabs);
diff --git a/scene/gui/tab_bar.h b/scene/gui/tab_bar.h
index b428538570..82ae8bce3f 100644
--- a/scene/gui/tab_bar.h
+++ b/scene/gui/tab_bar.h
@@ -126,7 +126,6 @@ protected:
 	Variant get_drag_data(const Point2 &p_point) override;
 	bool can_drop_data(const Point2 &p_point, const Variant &p_data) const override;
 	void drop_data(const Point2 &p_point, const Variant &p_data) override;
-	int get_tab_idx_at_point(const Point2 &p_point) const;
 
 public:
 	void add_tab(const String &p_str = "", const Ref<Texture2D> &p_icon = Ref<Texture2D>());
@@ -156,13 +155,15 @@ public:
 	void set_tab_button_icon(int p_tab, const Ref<Texture2D> &p_icon);
 	Ref<Texture2D> get_tab_button_icon(int p_tab) const;
 
+	int get_tab_idx_at_point(const Point2 &p_point) const;
+
 	void set_tab_alignment(AlignmentMode p_alignment);
 	AlignmentMode get_tab_alignment() const;
 
 	void set_clip_tabs(bool p_clip_tabs);
 	bool get_clip_tabs() const;
 
-	void move_tab(int from, int to);
+	void move_tab(int p_from, int p_to);
 
 	void set_tab_close_display_policy(CloseButtonDisplayPolicy p_policy);
 	CloseButtonDisplayPolicy get_tab_close_display_policy() const;
diff --git a/scene/gui/tab_container.cpp b/scene/gui/tab_container.cpp
index 31a5e41086..9953637e4f 100644
--- a/scene/gui/tab_container.cpp
+++ b/scene/gui/tab_container.cpp
@@ -30,44 +30,17 @@
 
 #include "tab_container.h"
 
-#include "core/object/message_queue.h"
-#include "core/string/translation.h"
 #include "scene/gui/box_container.h"
 #include "scene/gui/label.h"
 #include "scene/gui/texture_rect.h"
 
 int TabContainer::_get_top_margin() const {
-	if (!tabs_visible) {
-		return 0;
+	int height = 0;
+	if (tabs_visible && get_tab_count() > 0) {
+		height = tab_bar->get_minimum_size().height;
 	}
 
-	// Respect the minimum tab height.
-	Ref<StyleBox> tab_unselected = get_theme_stylebox(SNAME("tab_unselected"));
-	Ref<StyleBox> tab_selected = get_theme_stylebox(SNAME("tab_selected"));
-	Ref<StyleBox> tab_disabled = get_theme_stylebox(SNAME("tab_disabled"));
-
-	int tab_height = MAX(MAX(tab_unselected->get_minimum_size().height, tab_selected->get_minimum_size().height), tab_disabled->get_minimum_size().height);
-
-	// Font height or higher icon wins.
-	int content_height = 0;
-
-	Vector<Control *> tabs = _get_tabs();
-	for (int i = 0; i < tabs.size(); i++) {
-		content_height = MAX(content_height, text_buf[i]->get_size().y);
-
-		Control *c = tabs[i];
-		if (!c->has_meta("_tab_icon")) {
-			continue;
-		}
-
-		Ref<Texture2D> tex = c->get_meta("_tab_icon");
-		if (!tex.is_valid()) {
-			continue;
-		}
-		content_height = MAX(content_height, tex->get_size().height);
-	}
-
-	return tab_height + content_height;
+	return height;
 }
 
 void TabContainer::gui_input(const Ref<InputEvent> &p_event) {
@@ -113,77 +86,6 @@ void TabContainer::gui_input(const Ref<InputEvent> &p_event) {
 				return;
 			}
 		}
-
-		// Do not activate tabs when tabs is empty.
-		if (get_tab_count() == 0) {
-			return;
-		}
-
-		Vector<Control *> tabs = _get_tabs();
-
-		// Handle navigation buttons.
-		if (buttons_visible_cache) {
-			int popup_ofs = 0;
-			if (popup) {
-				popup_ofs = menu->get_width();
-			}
-
-			Ref<Texture2D> increment = get_theme_icon(SNAME("increment"));
-			Ref<Texture2D> decrement = get_theme_icon(SNAME("decrement"));
-			if (is_layout_rtl()) {
-				if (pos.x < popup_ofs + decrement->get_width()) {
-					if (last_tab_cache < tabs.size() - 1) {
-						first_tab_cache += 1;
-						update();
-					}
-					return;
-				} else if (pos.x < popup_ofs + increment->get_width() + decrement->get_width()) {
-					if (first_tab_cache > 0) {
-						first_tab_cache -= 1;
-						update();
-					}
-					return;
-				}
-			} else {
-				if (pos.x > size.width - increment->get_width() - popup_ofs && pos.x) {
-					if (last_tab_cache < tabs.size() - 1) {
-						first_tab_cache += 1;
-						update();
-					}
-					return;
-				} else if (pos.x > size.width - increment->get_width() - decrement->get_width() - popup_ofs) {
-					if (first_tab_cache > 0) {
-						first_tab_cache -= 1;
-						update();
-					}
-					return;
-				}
-			}
-		}
-
-		// Activate the clicked tab.
-		if (is_layout_rtl()) {
-			pos.x = size.width - pos.x;
-		}
-
-		if (pos.x < tabs_ofs_cache) {
-			return;
-		}
-
-		pos.x -= tabs_ofs_cache;
-		for (int i = first_tab_cache; i <= last_tab_cache; i++) {
-			if (get_tab_hidden(i)) {
-				continue;
-			}
-			int tab_width = _get_tab_width(i);
-			if (pos.x < tab_width) {
-				if (!get_tab_disabled(i)) {
-					set_current_tab(i);
-				}
-				break;
-			}
-			pos.x -= tab_width;
-		}
 	}
 
 	Ref<InputEventMouseMotion> mm = p_event;
@@ -194,9 +96,8 @@ void TabContainer::gui_input(const Ref<InputEvent> &p_event) {
 
 		// Mouse must be on tabs in the tab header area.
 		if (pos.y > _get_top_margin()) {
-			if (menu_hovered || highlight_arrow > -1) {
+			if (menu_hovered) {
 				menu_hovered = false;
-				highlight_arrow = -1;
 				update();
 			}
 			return;
@@ -208,7 +109,6 @@ void TabContainer::gui_input(const Ref<InputEvent> &p_event) {
 				if (pos.x <= menu->get_width()) {
 					if (!menu_hovered) {
 						menu_hovered = true;
-						highlight_arrow = -1;
 						update();
 						return;
 					}
@@ -220,7 +120,6 @@ void TabContainer::gui_input(const Ref<InputEvent> &p_event) {
 				if (pos.x >= size.width - menu->get_width()) {
 					if (!menu_hovered) {
 						menu_hovered = true;
-						highlight_arrow = -1;
 						update();
 						return;
 					}
@@ -234,102 +133,19 @@ void TabContainer::gui_input(const Ref<InputEvent> &p_event) {
 				return;
 			}
 		}
-
-		// Do not activate tabs when tabs is empty.
-		if ((get_tab_count() == 0 || !buttons_visible_cache) && menu_hovered) {
-			highlight_arrow = -1;
-			update();
-			return;
-		}
-
-		int popup_ofs = 0;
-		if (popup) {
-			popup_ofs = menu->get_width();
-		}
-
-		Ref<Texture2D> increment = get_theme_icon(SNAME("increment"));
-		Ref<Texture2D> decrement = get_theme_icon(SNAME("decrement"));
-
-		if (is_layout_rtl()) {
-			if (pos.x <= popup_ofs + decrement->get_width()) {
-				if (highlight_arrow != 1) {
-					highlight_arrow = 1;
-					update();
-				}
-			} else if (pos.x <= popup_ofs + increment->get_width() + decrement->get_width()) {
-				if (highlight_arrow != 0) {
-					highlight_arrow = 0;
-					update();
-				}
-			} else if (highlight_arrow > -1) {
-				highlight_arrow = -1;
-				update();
-			}
-		} else {
-			if (pos.x >= size.width - increment->get_width() - popup_ofs) {
-				if (highlight_arrow != 1) {
-					highlight_arrow = 1;
-					update();
-				}
-			} else if (pos.x >= size.width - increment->get_width() - decrement->get_width() - popup_ofs) {
-				if (highlight_arrow != 0) {
-					highlight_arrow = 0;
-					update();
-				}
-			} else if (highlight_arrow > -1) {
-				highlight_arrow = -1;
-				update();
-			}
-		}
 	}
 }
 
 void TabContainer::_notification(int p_what) {
 	switch (p_what) {
+		case NOTIFICATION_READY:
 		case NOTIFICATION_RESIZED: {
-			Vector<Control *> tabs = _get_tabs();
-			int side_margin = get_theme_constant(SNAME("side_margin"));
-			Ref<Texture2D> menu = get_theme_icon(SNAME("menu"));
-			Ref<Texture2D> increment = get_theme_icon(SNAME("increment"));
-			Ref<Texture2D> decrement = get_theme_icon(SNAME("decrement"));
-			int header_width = get_size().width - side_margin * 2;
-
-			// Find the width of the header area.
-			Popup *popup = get_popup();
-			if (popup) {
-				header_width -= menu->get_width();
-			}
-			if (buttons_visible_cache) {
-				header_width -= increment->get_width() + decrement->get_width();
-			}
-			if (popup || buttons_visible_cache) {
-				header_width += side_margin;
-			}
-
-			// Find the width of all tabs after first_tab_cache.
-			int all_tabs_width = 0;
-			for (int i = first_tab_cache; i < tabs.size(); i++) {
-				int tab_width = _get_tab_width(i);
-				all_tabs_width += tab_width;
-			}
-
-			// Check if tabs before first_tab_cache would fit into the header area.
-			for (int i = first_tab_cache - 1; i >= 0; i--) {
-				int tab_width = _get_tab_width(i);
-
-				if (all_tabs_width + tab_width > header_width) {
-					break;
-				}
-
-				all_tabs_width += tab_width;
-				first_tab_cache--;
-			}
+			_update_margins();
 		} break;
 
 		case NOTIFICATION_DRAW: {
 			RID canvas = get_canvas_item();
 			Size2 size = get_size();
-			bool rtl = is_layout_rtl();
 
 			// Draw only the tab area if the header is hidden.
 			Ref<StyleBox> panel = get_theme_stylebox(SNAME("panel"));
@@ -338,481 +154,171 @@ void TabContainer::_notification(int p_what) {
 				return;
 			}
 
-			Vector<Control *> tabs = _get_tabs();
-			Ref<StyleBox> tab_unselected = get_theme_stylebox(SNAME("tab_unselected"));
-			Ref<StyleBox> tab_selected = get_theme_stylebox(SNAME("tab_selected"));
-			Ref<StyleBox> tab_disabled = get_theme_stylebox(SNAME("tab_disabled"));
-			Ref<Texture2D> increment = get_theme_icon(SNAME("increment"));
-			Ref<Texture2D> increment_hl = get_theme_icon(SNAME("increment_highlight"));
-			Ref<Texture2D> decrement = get_theme_icon(SNAME("decrement"));
-			Ref<Texture2D> decrement_hl = get_theme_icon(SNAME("decrement_highlight"));
-			Ref<Texture2D> menu = get_theme_icon(SNAME("menu"));
-			Ref<Texture2D> menu_hl = get_theme_icon(SNAME("menu_highlight"));
-			Color font_selected_color = get_theme_color(SNAME("font_selected_color"));
-			Color font_unselected_color = get_theme_color(SNAME("font_unselected_color"));
-			Color font_disabled_color = get_theme_color(SNAME("font_disabled_color"));
-			int side_margin = get_theme_constant(SNAME("side_margin"));
-
-			// Find out start and width of the header area.
-			int header_x = side_margin;
-			int header_width = size.width - side_margin * 2;
 			int header_height = _get_top_margin();
-			Popup *popup = get_popup();
-			if (popup) {
-				header_width -= menu->get_width();
-			}
-
-			// Check if all tabs would fit into the header area.
-			int all_tabs_width = 0;
-			for (int i = 0; i < tabs.size(); i++) {
-				if (get_tab_hidden(i)) {
-					continue;
-				}
-				int tab_width = _get_tab_width(i);
-				all_tabs_width += tab_width;
-
-				if (all_tabs_width > header_width) {
-					// Not all tabs are visible at the same time - reserve space for navigation buttons.
-					buttons_visible_cache = true;
-					header_width -= decrement->get_width() + increment->get_width();
-					break;
-				} else {
-					buttons_visible_cache = false;
-				}
-			}
-			// With buttons, a right side margin does not need to be respected.
-			if (popup || buttons_visible_cache) {
-				header_width += side_margin;
-			}
-
-			if (!buttons_visible_cache) {
-				first_tab_cache = 0;
-			}
-
-			// Go through the visible tabs to find the width they occupy.
-			all_tabs_width = 0;
-			Vector<int> tab_widths;
-			for (int i = first_tab_cache; i < tabs.size(); i++) {
-				if (get_tab_hidden(i)) {
-					tab_widths.push_back(0);
-					continue;
-				}
-				int tab_width = _get_tab_width(i);
-				if (all_tabs_width + tab_width > header_width && tab_widths.size() > 0) {
-					break;
-				}
-				all_tabs_width += tab_width;
-				tab_widths.push_back(tab_width);
-			}
-
-			// Find the offset at which to draw tabs, according to the alignment.
-			switch (alignment) {
-				case ALIGNMENT_LEFT:
-					tabs_ofs_cache = header_x;
-					break;
-				case ALIGNMENT_CENTER:
-					tabs_ofs_cache = header_x + (header_width / 2) - (all_tabs_width / 2);
-					break;
-				case ALIGNMENT_RIGHT:
-					tabs_ofs_cache = header_x + header_width - all_tabs_width;
-					break;
-			}
-
-			if (all_tabs_in_front) {
-				// Draw the tab area.
-				panel->draw(canvas, Rect2(0, header_height, size.width, size.height - header_height));
-			}
-
-			// Draw unselected tabs in back
-			int x = 0;
-			int x_current = 0;
-			int index = 0;
-			for (int i = 0; i < tab_widths.size(); i++) {
-				index = i + first_tab_cache;
-				if (get_tab_hidden(index)) {
-					continue;
-				}
-
-				int tab_width = tab_widths[i];
-				if (index == current) {
-					x_current = x;
-				} else if (get_tab_disabled(index)) {
-					if (rtl) {
-						_draw_tab(tab_disabled, font_disabled_color, index, size.width - (tabs_ofs_cache + x) - tab_width);
-					} else {
-						_draw_tab(tab_disabled, font_disabled_color, index, tabs_ofs_cache + x);
-					}
-				} else {
-					if (rtl) {
-						_draw_tab(tab_unselected, font_unselected_color, index, size.width - (tabs_ofs_cache + x) - tab_width);
-					} else {
-						_draw_tab(tab_unselected, font_unselected_color, index, tabs_ofs_cache + x);
-					}
-				}
 
-				x += tab_width;
-				last_tab_cache = index;
-			}
+			panel->draw(canvas, Rect2(0, header_height, size.width, size.height - header_height));
 
-			if (!all_tabs_in_front) {
-				// Draw the tab area.
-				panel->draw(canvas, Rect2(0, header_height, size.width, size.height - header_height));
-			}
+			// Draw the popup menu.
+			if (get_popup()) {
+				Ref<Texture2D> menu = get_theme_icon(SNAME("menu"));
+				Ref<Texture2D> menu_hl = get_theme_icon(SNAME("menu_highlight"));
 
-			// Draw selected tab in front. Only draw selected tab when it's in visible range.
-			if (tabs.size() > 0 && current - first_tab_cache < tab_widths.size() && current >= first_tab_cache) {
-				Ref<StyleBox> current_style_box = get_tab_disabled(current) ? tab_disabled : tab_selected;
-				if (rtl) {
-					_draw_tab(current_style_box, font_selected_color, current, size.width - (tabs_ofs_cache + x_current) - tab_widths[current]);
-				} else {
-					_draw_tab(current_style_box, font_selected_color, current, tabs_ofs_cache + x_current);
-				}
-			}
+				int x = is_layout_rtl() ? 0 : get_size().width - menu->get_width();
 
-			// Draw the popup menu.
-			if (rtl) {
-				x = 0;
-			} else {
-				x = get_size().width;
-			}
-			if (popup) {
-				if (!rtl) {
-					x -= menu->get_width();
-				}
 				if (menu_hovered) {
 					menu_hl->draw(get_canvas_item(), Size2(x, (header_height - menu_hl->get_height()) / 2));
 				} else {
 					menu->draw(get_canvas_item(), Size2(x, (header_height - menu->get_height()) / 2));
 				}
-				if (rtl) {
-					x += menu->get_width();
-				}
-			}
-
-			// Draw the navigation buttons.
-			if (buttons_visible_cache) {
-				if (rtl) {
-					if (last_tab_cache < tabs.size() - 1) {
-						draw_texture(highlight_arrow == 1 ? decrement_hl : decrement, Point2(x, (header_height - increment->get_height()) / 2));
-					} else {
-						draw_texture(decrement, Point2(x, (header_height - increment->get_height()) / 2), Color(1, 1, 1, 0.5));
-					}
-					x += increment->get_width();
-
-					if (first_tab_cache > 0) {
-						draw_texture(highlight_arrow == 0 ? increment_hl : increment, Point2(x, (header_height - decrement->get_height()) / 2));
-					} else {
-						draw_texture(increment, Point2(x, (header_height - decrement->get_height()) / 2), Color(1, 1, 1, 0.5));
-					}
-					x += decrement->get_width();
-				} else {
-					x -= increment->get_width();
-					if (last_tab_cache < tabs.size() - 1) {
-						draw_texture(highlight_arrow == 1 ? increment_hl : increment, Point2(x, (header_height - increment->get_height()) / 2));
-					} else {
-						draw_texture(increment, Point2(x, (header_height - increment->get_height()) / 2), Color(1, 1, 1, 0.5));
-					}
-
-					x -= decrement->get_width();
-					if (first_tab_cache > 0) {
-						draw_texture(highlight_arrow == 0 ? decrement_hl : decrement, Point2(x, (header_height - decrement->get_height()) / 2));
-					} else {
-						draw_texture(decrement, Point2(x, (header_height - decrement->get_height()) / 2), Color(1, 1, 1, 0.5));
-					}
-				}
 			}
 		} break;
 
 		case NOTIFICATION_TRANSLATION_CHANGED:
 		case NOTIFICATION_LAYOUT_DIRECTION_CHANGED:
 		case NOTIFICATION_THEME_CHANGED: {
-			Vector<Control *> tabs = _get_tabs();
-			for (int i = 0; i < tabs.size(); i++) {
-				text_buf.write[i]->clear();
-			}
-			_theme_changing = true;
+			theme_changing = true;
 			call_deferred(SNAME("_on_theme_changed")); // Wait until all changed theme.
 		} break;
 	}
 }
 
-void TabContainer::_draw_tab(Ref<StyleBox> &p_tab_style, Color &p_font_color, int p_index, float p_x) {
-	Control *control = get_tab_control(p_index);
-	RID canvas = get_canvas_item();
-	Color font_outline_color = get_theme_color(SNAME("font_outline_color"));
-	int outline_size = get_theme_constant(SNAME("outline_size"));
-	int icon_text_distance = get_theme_constant(SNAME("icon_separation"));
-	int tab_width = _get_tab_width(p_index);
-	int header_height = _get_top_margin();
-
-	// Draw the tab background.
-	Rect2 tab_rect(p_x, 0, tab_width, header_height);
-	p_tab_style->draw(canvas, tab_rect);
-
-	// Draw the tab contents.
-	String text = control->has_meta("_tab_name") ? String(atr(String(control->get_meta("_tab_name")))) : String(atr(control->get_name()));
-
-	int x_content = tab_rect.position.x + p_tab_style->get_margin(SIDE_LEFT);
-	int top_margin = p_tab_style->get_margin(SIDE_TOP);
-	int y_center = top_margin + (tab_rect.size.y - p_tab_style->get_minimum_size().y) / 2;
-
-	// Draw the tab icon.
-	if (control->has_meta("_tab_icon")) {
-		Ref<Texture2D> icon = control->get_meta("_tab_icon");
-		if (icon.is_valid()) {
-			int y = y_center - (icon->get_height() / 2);
-			icon->draw(canvas, Point2i(x_content, y));
-			if (!text.is_empty()) {
-				x_content += icon->get_width() + icon_text_distance;
-			}
-		}
-	}
-
-	// Draw the tab text.
-	Point2i text_pos(x_content, y_center - text_buf[p_index]->get_size().y / 2);
-	if (outline_size > 0 && font_outline_color.a > 0) {
-		text_buf[p_index]->draw_outline(canvas, text_pos, outline_size, font_outline_color);
-	}
-	text_buf[p_index]->draw(canvas, text_pos, p_font_color);
-}
-
-void TabContainer::_refresh_texts() {
-	text_buf.clear();
-	Vector<Control *> tabs = _get_tabs();
-	bool rtl = is_layout_rtl();
-	Ref<Font> font = get_theme_font(SNAME("font"));
-	int font_size = get_theme_font_size(SNAME("font_size"));
-	for (int i = 0; i < tabs.size(); i++) {
-		Control *control = Object::cast_to<Control>(tabs[i]);
-		String text = control->has_meta("_tab_name") ? String(atr(String(control->get_meta("_tab_name")))) : String(atr(control->get_name()));
-
-		Ref<TextLine> name;
-		name.instantiate();
-		name->set_direction(rtl ? TextServer::DIRECTION_RTL : TextServer::DIRECTION_LTR);
-		name->add_string(text, font, font_size, Dictionary(), TranslationServer::get_singleton()->get_tool_locale());
-		text_buf.push_back(name);
-	}
-}
-
 void TabContainer::_on_theme_changed() {
-	if (!_theme_changing) {
+	if (!theme_changing) {
 		return;
 	}
 
-	_refresh_texts();
-
-	update_minimum_size();
+	tab_bar->add_theme_style_override(SNAME("tab_unselected"), get_theme_stylebox(SNAME("tab_unselected")));
+	tab_bar->add_theme_style_override(SNAME("tab_selected"), get_theme_stylebox(SNAME("tab_selected")));
+	tab_bar->add_theme_style_override(SNAME("tab_disabled"), get_theme_stylebox(SNAME("tab_disabled")));
+	tab_bar->add_theme_icon_override(SNAME("increment"), get_theme_icon(SNAME("increment")));
+	tab_bar->add_theme_icon_override(SNAME("increment_highlight"), get_theme_icon(SNAME("increment_highlight")));
+	tab_bar->add_theme_icon_override(SNAME("decrement"), get_theme_icon(SNAME("decrement")));
+	tab_bar->add_theme_icon_override(SNAME("decrement_highlight"), get_theme_icon(SNAME("decrement_highlight")));
+	tab_bar->add_theme_color_override(SNAME("font_selected_color"), get_theme_color(SNAME("font_selected_color")));
+	tab_bar->add_theme_color_override(SNAME("font_unselected_color"), get_theme_color(SNAME("font_unselected_color")));
+	tab_bar->add_theme_color_override(SNAME("font_disabled_color"), get_theme_color(SNAME("font_disabled_color")));
+	tab_bar->add_theme_color_override(SNAME("font_outline_color"), get_theme_color(SNAME("font_outline_color")));
+	tab_bar->add_theme_font_override(SNAME("font"), get_theme_font(SNAME("font")));
+	tab_bar->add_theme_constant_override(SNAME("font_size"), get_theme_constant(SNAME("font_size")));
+	tab_bar->add_theme_constant_override(SNAME("icon_separation"), get_theme_constant(SNAME("icon_separation")));
+	tab_bar->add_theme_constant_override(SNAME("outline_size"), get_theme_constant(SNAME("outline_size")));
+
+	_update_margins();
 	if (get_tab_count() > 0) {
 		_repaint();
-		update();
+	} else {
+		update_minimum_size();
 	}
-	_theme_changing = false;
+	update();
+
+	theme_changing = false;
 }
 
 void TabContainer::_repaint() {
 	Ref<StyleBox> sb = get_theme_stylebox(SNAME("panel"));
-	Vector<Control *> tabs = _get_tabs();
-	for (int i = 0; i < tabs.size(); i++) {
-		Control *c = tabs[i];
+	Vector<Control *> controls = _get_tab_controls();
+	int current = get_current_tab();
+
+	for (int i = 0; i < controls.size(); i++) {
+		Control *c = controls[i];
+
 		if (i == current) {
 			c->show();
 			c->set_anchors_and_offsets_preset(Control::PRESET_WIDE);
+
 			if (tabs_visible) {
 				c->set_offset(SIDE_TOP, _get_top_margin());
 			}
+
 			c->set_offset(SIDE_TOP, c->get_offset(SIDE_TOP) + sb->get_margin(SIDE_TOP));
 			c->set_offset(SIDE_LEFT, c->get_offset(SIDE_LEFT) + sb->get_margin(SIDE_LEFT));
 			c->set_offset(SIDE_RIGHT, c->get_offset(SIDE_RIGHT) - sb->get_margin(SIDE_RIGHT));
 			c->set_offset(SIDE_BOTTOM, c->get_offset(SIDE_BOTTOM) - sb->get_margin(SIDE_BOTTOM));
-
 		} else {
 			c->hide();
 		}
 	}
-}
-
-void TabContainer::_on_mouse_exited() {
-	if (menu_hovered || highlight_arrow > -1) {
-		menu_hovered = false;
-		highlight_arrow = -1;
-		update();
-	}
-}
-
-int TabContainer::_get_tab_width(int p_index) const {
-	ERR_FAIL_INDEX_V(p_index, get_tab_count(), 0);
-	Control *control = get_tab_control(p_index);
-	if (!control || get_tab_hidden(p_index)) {
-		return 0;
-	}
-
-	// Get the width of the text displayed on the tab.
-	Ref<Font> font = get_theme_font(SNAME("font"));
-	int font_size = get_theme_font_size(SNAME("font_size"));
-	String text = control->has_meta("_tab_name") ? String(atr(String(control->get_meta("_tab_name")))) : String(atr(control->get_name()));
-	int width = font->get_string_size(text, font_size).width;
-
-	// Add space for a tab icon.
-	if (control->has_meta("_tab_icon")) {
-		Ref<Texture2D> icon = control->get_meta("_tab_icon");
-		if (icon.is_valid()) {
-			width += icon->get_width();
-			if (!text.is_empty()) {
-				width += get_theme_constant(SNAME("icon_separation"));
-			}
-		}
-	}
-
-	// Respect a minimum size.
-	Ref<StyleBox> tab_unselected = get_theme_stylebox(SNAME("tab_unselected"));
-	Ref<StyleBox> tab_selected = get_theme_stylebox(SNAME("tab_selected"));
-	Ref<StyleBox> tab_disabled = get_theme_stylebox(SNAME("tab_disabled"));
-	if (get_tab_disabled(p_index)) {
-		width += tab_disabled->get_minimum_size().width;
-	} else if (p_index == current) {
-		width += tab_selected->get_minimum_size().width;
-	} else {
-		width += tab_unselected->get_minimum_size().width;
-	}
 
-	return width;
+	update_minimum_size();
 }
 
-Vector<Control *> TabContainer::_get_tabs() const {
-	Vector<Control *> controls;
-	for (int i = 0; i < get_child_count(); i++) {
-		Control *control = Object::cast_to<Control>(get_child(i));
-		if (!control || control->is_set_as_top_level()) {
-			continue;
-		}
-
-		controls.push_back(control);
-	}
-	return controls;
-}
+void TabContainer::_update_margins() {
+	int menu_width = get_theme_icon(SNAME("menu"))->get_width();
+	int side_margin = get_theme_constant(SNAME("side_margin"));
 
-void TabContainer::_child_renamed_callback() {
-	_refresh_texts();
-	update();
-}
+	// Directly check for validity, to avoid errors when quitting.
+	bool has_popup = popup_obj_id.is_valid();
 
-void TabContainer::add_child_notify(Node *p_child) {
-	Container::add_child_notify(p_child);
+	if (get_tab_count() == 0) {
+		tab_bar->set_offset(SIDE_LEFT, 0);
+		tab_bar->set_offset(SIDE_RIGHT, has_popup ? -menu_width : 0);
 
-	Control *c = Object::cast_to<Control>(p_child);
-	if (!c || c->is_set_as_top_level()) {
 		return;
 	}
 
-	_refresh_texts();
-	call_deferred(SNAME("_repaint"));
-	update();
-
-	bool first = (_get_tabs().size() == 1);
-	if (first) {
-		current = 0;
-		previous = 0;
-	}
-
-	p_child->connect("renamed", callable_mp(this, &TabContainer::_child_renamed_callback));
-	if (first && is_inside_tree()) {
-		emit_signal(SNAME("tab_changed"), current);
-	}
-}
-
-void TabContainer::move_child_notify(Node *p_child) {
-	Container::move_child_notify(p_child);
+	switch (get_tab_alignment()) {
+		case TabBar::ALIGNMENT_LEFT: {
+			tab_bar->set_offset(SIDE_LEFT, side_margin);
+			tab_bar->set_offset(SIDE_RIGHT, has_popup ? -menu_width : 0);
+		} break;
 
-	Control *c = Object::cast_to<Control>(p_child);
-	if (!c || c->is_set_as_top_level()) {
-		return;
-	}
+		case TabBar::ALIGNMENT_CENTER: {
+			tab_bar->set_offset(SIDE_LEFT, 0);
+			tab_bar->set_offset(SIDE_RIGHT, has_popup ? -menu_width : 0);
+		} break;
 
-	_update_current_tab();
-	update();
-}
+		case TabBar::ALIGNMENT_RIGHT: {
+			tab_bar->set_offset(SIDE_LEFT, 0);
 
-int TabContainer::get_tab_count() const {
-	return _get_tabs().size();
-}
-
-void TabContainer::set_current_tab(int p_current) {
-	ERR_FAIL_INDEX(p_current, get_tab_count());
+			if (has_popup) {
+				tab_bar->set_offset(SIDE_RIGHT, -menu_width);
+				return;
+			}
 
-	int pending_previous = current;
-	current = p_current;
+			int first_tab_pos = tab_bar->get_tab_rect(0).position.x;
+			Rect2 last_tab_rect = tab_bar->get_tab_rect(get_tab_count() - 1);
+			int total_tabs_width = last_tab_rect.position.x - first_tab_pos + last_tab_rect.size.width;
 
-	_repaint();
+			// Calculate if all the tabs would still fit if the margin was present.
+			if (get_clip_tabs() && (tab_bar->get_offset_buttons_visible() || (get_tab_count() > 1 && (total_tabs_width + side_margin) > get_size().width))) {
+				tab_bar->set_offset(SIDE_RIGHT, has_popup ? -menu_width : 0);
+			} else {
+				tab_bar->set_offset(SIDE_RIGHT, -side_margin);
+			}
+		} break;
 
-	if (pending_previous == current) {
-		emit_signal(SNAME("tab_selected"), current);
-	} else {
-		previous = pending_previous;
-		emit_signal(SNAME("tab_selected"), current);
-		emit_signal(SNAME("tab_changed"), current);
+		case TabBar::ALIGNMENT_MAX:
+			break; // Can't happen, but silences warning.
 	}
-
-	update();
-}
-
-int TabContainer::get_current_tab() const {
-	return current;
 }
 
-int TabContainer::get_previous_tab() const {
-	return previous;
-}
-
-Control *TabContainer::get_tab_control(int p_idx) const {
-	Vector<Control *> tabs = _get_tabs();
-	if (p_idx >= 0 && p_idx < tabs.size()) {
-		return tabs[p_idx];
-	} else {
-		return nullptr;
+void TabContainer::_on_mouse_exited() {
+	if (menu_hovered) {
+		menu_hovered = false;
+		update();
 	}
 }
 
-Control *TabContainer::get_current_tab_control() const {
-	return get_tab_control(current);
-}
-
-void TabContainer::remove_child_notify(Node *p_child) {
-	Container::remove_child_notify(p_child);
+Vector<Control *> TabContainer::_get_tab_controls() const {
+	Vector<Control *> controls;
+	for (int i = 0; i < get_child_count(); i++) {
+		Control *control = Object::cast_to<Control>(get_child(i));
+		if (!control || control->is_set_as_top_level() || control == tab_bar) {
+			continue;
+		}
 
-	Control *c = Object::cast_to<Control>(p_child);
-	if (!c || c->is_set_as_top_level()) {
-		return;
+		controls.push_back(control);
 	}
 
-	// Defer the call because tab is not yet removed (remove_child_notify is called right before p_child is actually removed).
-	call_deferred(SNAME("_update_current_tab"));
-
-	p_child->disconnect("renamed", callable_mp(this, &TabContainer::_child_renamed_callback));
-
-	update();
-}
-
-void TabContainer::_update_current_tab() {
-	_refresh_texts();
-
-	int tc = get_tab_count();
-	if (current >= tc) {
-		current = tc - 1;
-	}
-	if (current < 0) {
-		current = 0;
-	} else {
-		set_current_tab(current);
-	}
+	return controls;
 }
 
-Variant TabContainer::get_drag_data(const Point2 &p_point) {
+Variant TabContainer::_get_drag_data_fw(const Point2 &p_point, Control *p_from_control) {
 	if (!drag_to_rearrange_enabled) {
 		return Variant();
 	}
 
 	int tab_over = get_tab_idx_at_point(p_point);
-
 	if (tab_over < 0) {
 		return Variant();
 	}
@@ -825,18 +331,20 @@ Variant TabContainer::get_drag_data(const Point2 &p_point) {
 		tf->set_texture(icon);
 		drag_preview->add_child(tf);
 	}
+
 	Label *label = memnew(Label(get_tab_title(tab_over)));
-	drag_preview->add_child(label);
 	set_drag_preview(drag_preview);
+	drag_preview->add_child(label);
 
 	Dictionary drag_data;
 	drag_data["type"] = "tabc_element";
 	drag_data["tabc_element"] = tab_over;
 	drag_data["from_path"] = get_path();
+
 	return drag_data;
 }
 
-bool TabContainer::can_drop_data(const Point2 &p_point, const Variant &p_data) const {
+bool TabContainer::_can_drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from_control) const {
 	if (!drag_to_rearrange_enabled) {
 		return false;
 	}
@@ -852,7 +360,7 @@ bool TabContainer::can_drop_data(const Point2 &p_point, const Variant &p_data) c
 		if (from_path == to_path) {
 			return true;
 		} else if (get_tabs_rearrange_group() != -1) {
-			// drag and drop between other TabContainers
+			// Drag and drop between other TabContainers.
 			Node *from_node = get_node(from_path);
 			TabContainer *from_tabc = Object::cast_to<TabContainer>(from_node);
 			if (from_tabc && from_tabc->get_tabs_rearrange_group() == get_tabs_rearrange_group()) {
@@ -860,10 +368,11 @@ bool TabContainer::can_drop_data(const Point2 &p_point, const Variant &p_data) c
 			}
 		}
 	}
+
 	return false;
 }
 
-void TabContainer::drop_data(const Point2 &p_point, const Variant &p_data) {
+void TabContainer::_drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from_control) {
 	if (!drag_to_rearrange_enabled) {
 		return;
 	}
@@ -883,85 +392,192 @@ void TabContainer::drop_data(const Point2 &p_point, const Variant &p_data) {
 			if (hover_now < 0) {
 				hover_now = get_tab_count() - 1;
 			}
-			move_child(get_tab_control(tab_from_id), get_tab_control(hover_now)->get_index());
+
+			move_child(get_tab_control(tab_from_id), get_tab_control(hover_now)->get_index(false));
 			set_current_tab(hover_now);
 		} else if (get_tabs_rearrange_group() != -1) {
-			// drag and drop between TabContainers
+			// Drag and drop between TabContainers.
 			Node *from_node = get_node(from_path);
 			TabContainer *from_tabc = Object::cast_to<TabContainer>(from_node);
 			if (from_tabc && from_tabc->get_tabs_rearrange_group() == get_tabs_rearrange_group()) {
 				Control *moving_tabc = from_tabc->get_tab_control(tab_from_id);
 				from_tabc->remove_child(moving_tabc);
-				add_child(moving_tabc, false, INTERNAL_MODE_FRONT);
+				add_child(moving_tabc, true);
+
 				if (hover_now < 0) {
 					hover_now = get_tab_count() - 1;
 				}
-				move_child(moving_tabc, get_tab_control(hover_now)->get_index());
+
+				move_child(moving_tabc, get_tab_control(hover_now)->get_index(false));
+
 				set_current_tab(hover_now);
-				emit_signal(SNAME("tab_changed"), hover_now);
 			}
 		}
 	}
-	update();
 }
 
-int TabContainer::get_tab_idx_at_point(const Point2 &p_point) const {
-	if (get_tab_count() == 0) {
-		return -1;
+void TabContainer::_on_tab_changed(int p_tab) {
+	call_deferred(SNAME("_repaint"));
+
+	emit_signal(SNAME("tab_changed"), p_tab);
+}
+
+void TabContainer::_on_tab_selected(int p_tab) {
+	if (p_tab != get_previous_tab()) {
+		call_deferred(SNAME("_repaint"));
 	}
 
-	// must be on tabs in the tab header area.
-	if (p_point.y > _get_top_margin()) {
-		return -1;
+	emit_signal(SNAME("tab_selected"), p_tab);
+}
+
+void TabContainer::_child_renamed_callback() {
+	Vector<Control *> controls = _get_tab_controls();
+	for (int i = 0; i < controls.size(); i++) {
+		if (!controls[i]->has_meta("_tab_name") && String(controls[i]->get_name()) != get_tab_title(i)) {
+			tab_bar->set_tab_title(i, controls[i]->get_name());
+			return;
+		}
 	}
+}
 
-	Size2 size = get_size();
-	int button_ofs = 0;
-	int px = p_point.x;
+void TabContainer::add_child_notify(Node *p_child) {
+	if (p_child == tab_bar) {
+		return;
+	}
+
+	Container::add_child_notify(p_child);
 
-	if (is_layout_rtl()) {
-		px = size.width - px;
+	Control *c = Object::cast_to<Control>(p_child);
+	if (!c || c->is_set_as_top_level()) {
+		return;
 	}
+	c->hide();
+
+	tab_bar->add_tab(p_child->get_name());
 
-	if (px < tabs_ofs_cache) {
-		return -1;
+	_update_margins();
+
+	p_child->connect("renamed", callable_mp(this, &TabContainer::_child_renamed_callback));
+
+	// TabBar won't emit the "tab_changed" signal when not inside the tree.
+	if (!is_inside_tree()) {
+		call_deferred("_repaint");
 	}
+}
 
-	Popup *popup = get_popup();
-	if (popup) {
-		Ref<Texture2D> menu = get_theme_icon(SNAME("menu"));
-		button_ofs += menu->get_width();
+void TabContainer::move_child_notify(Node *p_child) {
+	if (p_child == tab_bar) {
+		return;
 	}
-	if (buttons_visible_cache) {
-		Ref<Texture2D> increment = get_theme_icon(SNAME("increment"));
-		Ref<Texture2D> decrement = get_theme_icon(SNAME("decrement"));
-		button_ofs += increment->get_width() + decrement->get_width();
+
+	Container::move_child_notify(p_child);
+
+	Control *c = Object::cast_to<Control>(p_child);
+	if (c && !c->is_set_as_top_level()) {
+		int old_idx = -1;
+		String tab_name = c->has_meta("_tab_name") ? String(c->get_meta("_tab_name")) : String(c->get_name());
+
+		// Find the previous tab index of the control.
+		for (int i = 0; i < get_tab_count(); i++) {
+			if (get_tab_title(i) == tab_name) {
+				old_idx = i;
+				break;
+			}
+		}
+
+		tab_bar->move_tab(old_idx, get_tab_idx_from_control(c));
 	}
-	if (px > size.width - button_ofs) {
-		return -1;
+}
+
+void TabContainer::remove_child_notify(Node *p_child) {
+	if (p_child == tab_bar) {
+		return;
 	}
 
-	// get the tab at the point
-	Vector<Control *> tabs = _get_tabs();
-	px -= tabs_ofs_cache;
-	for (int i = first_tab_cache; i <= last_tab_cache; i++) {
-		int tab_width = _get_tab_width(i);
-		if (px < tab_width) {
+	Container::remove_child_notify(p_child);
+
+	Control *c = Object::cast_to<Control>(p_child);
+	if (!c || c->is_set_as_top_level()) {
+		return;
+	}
+
+	tab_bar->remove_tab(get_tab_idx_from_control(c));
+
+	_update_margins();
+
+	if (p_child->has_meta("_tab_name")) {
+		p_child->remove_meta("_tab_name");
+	}
+	p_child->disconnect("renamed", callable_mp(this, &TabContainer::_child_renamed_callback));
+
+	// TabBar won't emit the "tab_changed" signal when not inside the tree.
+	if (!is_inside_tree()) {
+		call_deferred("_repaint");
+	}
+}
+
+int TabContainer::get_tab_count() const {
+	return tab_bar->get_tab_count();
+}
+
+void TabContainer::set_current_tab(int p_current) {
+	tab_bar->set_current_tab(p_current);
+}
+
+int TabContainer::get_current_tab() const {
+	return tab_bar->get_current_tab();
+}
+
+int TabContainer::get_previous_tab() const {
+	return tab_bar->get_previous_tab();
+}
+
+Control *TabContainer::get_tab_control(int p_idx) const {
+	Vector<Control *> controls = _get_tab_controls();
+	if (p_idx >= 0 && p_idx < controls.size()) {
+		return controls[p_idx];
+	} else {
+		return nullptr;
+	}
+}
+
+Control *TabContainer::get_current_tab_control() const {
+	return get_tab_control(tab_bar->get_current_tab());
+}
+
+int TabContainer::get_tab_idx_at_point(const Point2 &p_point) const {
+	return tab_bar->get_tab_idx_at_point(p_point);
+}
+
+int TabContainer::get_tab_idx_from_control(Control *p_child) const {
+	ERR_FAIL_NULL_V(p_child, -1);
+	ERR_FAIL_COND_V(p_child->get_parent() != this, -1);
+
+	Vector<Control *> controls = _get_tab_controls();
+	for (int i = 0; i < controls.size(); i++) {
+		if (controls[i] == p_child) {
 			return i;
 		}
-		px -= tab_width;
 	}
+
 	return -1;
 }
 
-void TabContainer::set_tab_alignment(AlignmentMode p_alignment) {
-	ERR_FAIL_INDEX(p_alignment, 3);
-	alignment = p_alignment;
-	update();
+void TabContainer::set_tab_alignment(TabBar::AlignmentMode p_alignment) {
+	tab_bar->set_tab_alignment(p_alignment);
+	_update_margins();
 }
 
-TabContainer::AlignmentMode TabContainer::get_tab_alignment() const {
-	return alignment;
+TabBar::AlignmentMode TabContainer::get_tab_alignment() const {
+	return tab_bar->get_tab_alignment();
+}
+
+void TabContainer::set_clip_tabs(bool p_clip_tabs) {
+	tab_bar->set_clip_tabs(p_clip_tabs);
+}
+
+bool TabContainer::get_clip_tabs() const {
+	return tab_bar->get_clip_tabs();
 }
 
 void TabContainer::set_tabs_visible(bool p_visible) {
@@ -970,11 +586,12 @@ void TabContainer::set_tabs_visible(bool p_visible) {
 	}
 
 	tabs_visible = p_visible;
+	tab_bar->set_visible(tabs_visible);
 
-	Vector<Control *> tabs = _get_tabs();
-	for (int i = 0; i < tabs.size(); i++) {
-		Control *c = tabs[i];
-		if (p_visible) {
+	Vector<Control *> controls = _get_tab_controls();
+	for (int i = 0; i < controls.size(); i++) {
+		Control *c = controls[i];
+		if (tabs_visible) {
 			c->set_offset(SIDE_TOP, _get_top_margin());
 		} else {
 			c->set_offset(SIDE_TOP, 0);
@@ -996,7 +613,8 @@ void TabContainer::set_all_tabs_in_front(bool p_in_front) {
 
 	all_tabs_in_front = p_in_front;
 
-	update();
+	remove_child(tab_bar);
+	add_child(tab_bar, false, all_tabs_in_front ? INTERNAL_MODE_BACK : INTERNAL_MODE_FRONT);
 }
 
 bool TabContainer::is_all_tabs_in_front() const {
@@ -1006,95 +624,61 @@ bool TabContainer::is_all_tabs_in_front() const {
 void TabContainer::set_tab_title(int p_tab, const String &p_title) {
 	Control *child = get_tab_control(p_tab);
 	ERR_FAIL_COND(!child);
-	child->set_meta("_tab_name", p_title);
-	_refresh_texts();
-	update();
-}
 
-String TabContainer::get_tab_title(int p_tab) const {
-	Control *child = get_tab_control(p_tab);
-	ERR_FAIL_COND_V(!child, "");
-	if (child->has_meta("_tab_name")) {
-		return child->get_meta("_tab_name");
+	if (p_title.is_empty()) {
+		tab_bar->set_tab_title(p_tab, String(child->get_name()));
+
+		if (child->has_meta("_tab_name")) {
+			child->remove_meta("_tab_name");
+		}
 	} else {
-		return child->get_name();
+		tab_bar->set_tab_title(p_tab, p_title);
+		child->set_meta("_tab_name", p_title);
 	}
 }
 
+String TabContainer::get_tab_title(int p_tab) const {
+	return tab_bar->get_tab_title(p_tab);
+}
+
 void TabContainer::set_tab_icon(int p_tab, const Ref<Texture2D> &p_icon) {
-	Control *child = get_tab_control(p_tab);
-	ERR_FAIL_COND(!child);
-	child->set_meta("_tab_icon", p_icon);
-	update();
+	tab_bar->set_tab_icon(p_tab, p_icon);
 }
 
 Ref<Texture2D> TabContainer::get_tab_icon(int p_tab) const {
-	Control *child = get_tab_control(p_tab);
-	ERR_FAIL_COND_V(!child, Ref<Texture2D>());
-	if (child->has_meta("_tab_icon")) {
-		return child->get_meta("_tab_icon");
-	} else {
-		return Ref<Texture2D>();
-	}
+	return tab_bar->get_tab_icon(p_tab);
 }
 
 void TabContainer::set_tab_disabled(int p_tab, bool p_disabled) {
-	Control *child = get_tab_control(p_tab);
-	ERR_FAIL_COND(!child);
-	child->set_meta("_tab_disabled", p_disabled);
-	update();
+	tab_bar->set_tab_disabled(p_tab, p_disabled);
 }
 
-bool TabContainer::get_tab_disabled(int p_tab) const {
-	Control *child = get_tab_control(p_tab);
-	ERR_FAIL_COND_V(!child, false);
-	if (child->has_meta("_tab_disabled")) {
-		return child->get_meta("_tab_disabled");
-	} else {
-		return false;
-	}
+bool TabContainer::is_tab_disabled(int p_tab) const {
+	return tab_bar->is_tab_disabled(p_tab);
 }
 
 void TabContainer::set_tab_hidden(int p_tab, bool p_hidden) {
 	Control *child = get_tab_control(p_tab);
 	ERR_FAIL_COND(!child);
-	child->set_meta("_tab_hidden", p_hidden);
-	update();
-	for (int i = 0; i < get_tab_count(); i++) {
-		int try_tab = (p_tab + 1 + i) % get_tab_count();
-		if (get_tab_disabled(try_tab) || get_tab_hidden(try_tab)) {
-			continue;
-		}
-
-		set_current_tab(try_tab);
-		return;
-	}
 
-	//assumed no other tab can be switched to, just hide
+	tab_bar->set_tab_hidden(p_tab, p_hidden);
 	child->hide();
 }
 
-bool TabContainer::get_tab_hidden(int p_tab) const {
-	Control *child = get_tab_control(p_tab);
-	ERR_FAIL_COND_V(!child, false);
-	if (child->has_meta("_tab_hidden")) {
-		return child->get_meta("_tab_hidden");
-	} else {
-		return false;
-	}
+bool TabContainer::is_tab_hidden(int p_tab) const {
+	return tab_bar->is_tab_hidden(p_tab);
 }
 
 void TabContainer::get_translatable_strings(List<String> *p_strings) const {
-	Vector<Control *> tabs = _get_tabs();
-	for (int i = 0; i < tabs.size(); i++) {
-		Control *c = tabs[i];
+	Vector<Control *> controls = _get_tab_controls();
+	for (int i = 0; i < controls.size(); i++) {
+		Control *c = controls[i];
 
 		if (!c->has_meta("_tab_name")) {
 			continue;
 		}
 
 		String name = c->get_meta("_tab_name");
-
 		if (!name.is_empty()) {
 			p_strings->push_back(name);
 		}
@@ -1104,9 +688,26 @@ void TabContainer::get_translatable_strings(List<String> *p_strings) const {
 Size2 TabContainer::get_minimum_size() const {
 	Size2 ms;
 
-	Vector<Control *> tabs = _get_tabs();
-	for (int i = 0; i < tabs.size(); i++) {
-		Control *c = tabs[i];
+	if (tabs_visible) {
+		ms = tab_bar->get_minimum_size();
+
+		if (!get_clip_tabs()) {
+			if (get_popup()) {
+				ms.x += get_theme_icon(SNAME("menu"))->get_width();
+			}
+
+			int side_margin = get_theme_constant(SNAME("side_margin"));
+			if (side_margin > 0 && get_tab_alignment() != TabBar::ALIGNMENT_CENTER &&
+					(get_tab_alignment() != TabBar::ALIGNMENT_RIGHT || !get_popup())) {
+				ms.x += side_margin;
+			}
+		}
+	}
+
+	Vector<Control *> controls = _get_tab_controls();
+	int max_control_height = 0;
+	for (int i = 0; i < controls.size(); i++) {
+		Control *c = controls[i];
 
 		if (!c->is_visible_in_tree() && !use_hidden_tabs_for_min_size) {
 			continue;
@@ -1114,29 +715,28 @@ Size2 TabContainer::get_minimum_size() const {
 
 		Size2 cms = c->get_combined_minimum_size();
 		ms.x = MAX(ms.x, cms.x);
-		ms.y = MAX(ms.y, cms.y);
+		max_control_height = MAX(max_control_height, cms.y);
 	}
+	ms.y += max_control_height;
 
-	Ref<StyleBox> tab_unselected = get_theme_stylebox(SNAME("tab_unselected"));
-	Ref<StyleBox> tab_selected = get_theme_stylebox(SNAME("tab_selected"));
-	Ref<StyleBox> tab_disabled = get_theme_stylebox(SNAME("tab_disabled"));
-
-	if (tabs_visible) {
-		ms.y += MAX(MAX(tab_unselected->get_minimum_size().y, tab_selected->get_minimum_size().y), tab_disabled->get_minimum_size().y);
-		ms.y += _get_top_margin();
-	}
-
-	Ref<StyleBox> sb = get_theme_stylebox(SNAME("panel"));
-	ms += sb->get_minimum_size();
+	Size2 panel_ms = get_theme_stylebox(SNAME("panel"))->get_minimum_size();
+	ms.x = MAX(ms.x, panel_ms.x);
+	ms.y += panel_ms.y;
 
 	return ms;
 }
 
 void TabContainer::set_popup(Node *p_popup) {
-	ERR_FAIL_NULL(p_popup);
+	bool had_popup = get_popup();
+
 	Popup *popup = Object::cast_to<Popup>(p_popup);
 	popup_obj_id = popup ? popup->get_instance_id() : ObjectID();
-	update();
+
+	if (had_popup != bool(popup)) {
+		update();
+		_update_margins();
+		update_minimum_size();
+	}
 }
 
 Popup *TabContainer::get_popup() const {
@@ -1151,6 +751,7 @@ Popup *TabContainer::get_popup() const {
 			popup_obj_id = ObjectID();
 		}
 	}
+
 	return nullptr;
 }
 
@@ -1163,15 +764,16 @@ bool TabContainer::get_drag_to_rearrange_enabled() const {
 }
 
 void TabContainer::set_tabs_rearrange_group(int p_group_id) {
-	tabs_rearrange_group = p_group_id;
+	tab_bar->set_tabs_rearrange_group(p_group_id);
 }
 
 int TabContainer::get_tabs_rearrange_group() const {
-	return tabs_rearrange_group;
+	return tab_bar->get_tabs_rearrange_group();
 }
 
 void TabContainer::set_use_hidden_tabs_for_min_size(bool p_use_hidden_tabs) {
 	use_hidden_tabs_for_min_size = p_use_hidden_tabs;
+	update_minimum_size();
 }
 
 bool TabContainer::get_use_hidden_tabs_for_min_size() const {
@@ -1195,6 +797,8 @@ void TabContainer::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_tab_control", "tab_idx"), &TabContainer::get_tab_control);
 	ClassDB::bind_method(D_METHOD("set_tab_alignment", "alignment"), &TabContainer::set_tab_alignment);
 	ClassDB::bind_method(D_METHOD("get_tab_alignment"), &TabContainer::get_tab_alignment);
+	ClassDB::bind_method(D_METHOD("set_clip_tabs", "clip_tabs"), &TabContainer::set_clip_tabs);
+	ClassDB::bind_method(D_METHOD("get_clip_tabs"), &TabContainer::get_clip_tabs);
 	ClassDB::bind_method(D_METHOD("set_tabs_visible", "visible"), &TabContainer::set_tabs_visible);
 	ClassDB::bind_method(D_METHOD("are_tabs_visible"), &TabContainer::are_tabs_visible);
 	ClassDB::bind_method(D_METHOD("set_all_tabs_in_front", "is_front"), &TabContainer::set_all_tabs_in_front);
@@ -1204,23 +808,25 @@ void TabContainer::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_tab_icon", "tab_idx", "icon"), &TabContainer::set_tab_icon);
 	ClassDB::bind_method(D_METHOD("get_tab_icon", "tab_idx"), &TabContainer::get_tab_icon);
 	ClassDB::bind_method(D_METHOD("set_tab_disabled", "tab_idx", "disabled"), &TabContainer::set_tab_disabled);
-	ClassDB::bind_method(D_METHOD("get_tab_disabled", "tab_idx"), &TabContainer::get_tab_disabled);
+	ClassDB::bind_method(D_METHOD("is_tab_disabled", "tab_idx"), &TabContainer::is_tab_disabled);
 	ClassDB::bind_method(D_METHOD("set_tab_hidden", "tab_idx", "hidden"), &TabContainer::set_tab_hidden);
-	ClassDB::bind_method(D_METHOD("get_tab_hidden", "tab_idx"), &TabContainer::get_tab_hidden);
+	ClassDB::bind_method(D_METHOD("is_tab_hidden", "tab_idx"), &TabContainer::is_tab_hidden);
 	ClassDB::bind_method(D_METHOD("get_tab_idx_at_point", "point"), &TabContainer::get_tab_idx_at_point);
+	ClassDB::bind_method(D_METHOD("get_tab_idx_from_control", "control"), &TabContainer::get_tab_idx_from_control);
 	ClassDB::bind_method(D_METHOD("set_popup", "popup"), &TabContainer::set_popup);
 	ClassDB::bind_method(D_METHOD("get_popup"), &TabContainer::get_popup);
 	ClassDB::bind_method(D_METHOD("set_drag_to_rearrange_enabled", "enabled"), &TabContainer::set_drag_to_rearrange_enabled);
 	ClassDB::bind_method(D_METHOD("get_drag_to_rearrange_enabled"), &TabContainer::get_drag_to_rearrange_enabled);
 	ClassDB::bind_method(D_METHOD("set_tabs_rearrange_group", "group_id"), &TabContainer::set_tabs_rearrange_group);
 	ClassDB::bind_method(D_METHOD("get_tabs_rearrange_group"), &TabContainer::get_tabs_rearrange_group);
-
 	ClassDB::bind_method(D_METHOD("set_use_hidden_tabs_for_min_size", "enabled"), &TabContainer::set_use_hidden_tabs_for_min_size);
 	ClassDB::bind_method(D_METHOD("get_use_hidden_tabs_for_min_size"), &TabContainer::get_use_hidden_tabs_for_min_size);
 
 	ClassDB::bind_method(D_METHOD("_repaint"), &TabContainer::_repaint);
 	ClassDB::bind_method(D_METHOD("_on_theme_changed"), &TabContainer::_on_theme_changed);
-	ClassDB::bind_method(D_METHOD("_update_current_tab"), &TabContainer::_update_current_tab);
+	ClassDB::bind_method(D_METHOD("_get_drag_data_fw"), &TabContainer::_get_drag_data_fw);
+	ClassDB::bind_method(D_METHOD("_can_drop_data_fw"), &TabContainer::_can_drop_data_fw);
+	ClassDB::bind_method(D_METHOD("_drop_data_fw"), &TabContainer::_drop_data_fw);
 
 	ADD_SIGNAL(MethodInfo("tab_changed", PropertyInfo(Variant::INT, "tab")));
 	ADD_SIGNAL(MethodInfo("tab_selected", PropertyInfo(Variant::INT, "tab")));
@@ -1228,16 +834,20 @@ void TabContainer::_bind_methods() {
 
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "tab_alignment", PROPERTY_HINT_ENUM, "Left,Center,Right"), "set_tab_alignment", "get_tab_alignment");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "current_tab", PROPERTY_HINT_RANGE, "-1,4096,1", PROPERTY_USAGE_EDITOR), "set_current_tab", "get_current_tab");
+	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "clip_tabs"), "set_clip_tabs", "get_clip_tabs");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "tabs_visible"), "set_tabs_visible", "are_tabs_visible");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "all_tabs_in_front"), "set_all_tabs_in_front", "is_all_tabs_in_front");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "drag_to_rearrange_enabled"), "set_drag_to_rearrange_enabled", "get_drag_to_rearrange_enabled");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "use_hidden_tabs_for_min_size"), "set_use_hidden_tabs_for_min_size", "get_use_hidden_tabs_for_min_size");
-
-	BIND_ENUM_CONSTANT(ALIGNMENT_LEFT);
-	BIND_ENUM_CONSTANT(ALIGNMENT_CENTER);
-	BIND_ENUM_CONSTANT(ALIGNMENT_RIGHT);
 }
 
 TabContainer::TabContainer() {
+	tab_bar = memnew(TabBar);
+	tab_bar->set_drag_forwarding(this);
+	add_child(tab_bar, false, INTERNAL_MODE_FRONT);
+	tab_bar->set_anchors_and_offsets_preset(Control::PRESET_TOP_WIDE);
+	tab_bar->connect("tab_changed", callable_mp(this, &TabContainer::_on_tab_changed));
+	tab_bar->connect("tab_selected", callable_mp(this, &TabContainer::_on_tab_selected));
+
 	connect("mouse_exited", callable_mp(this, &TabContainer::_on_mouse_exited));
 }
diff --git a/scene/gui/tab_container.h b/scene/gui/tab_container.h
index ee1b3fea51..1322f08206 100644
--- a/scene/gui/tab_container.h
+++ b/scene/gui/tab_container.h
@@ -33,46 +33,32 @@
 
 #include "scene/gui/container.h"
 #include "scene/gui/popup.h"
-#include "scene/resources/text_line.h"
+#include "scene/gui/tab_bar.h"
 
 class TabContainer : public Container {
 	GDCLASS(TabContainer, Container);
 
-public:
-	enum AlignmentMode {
-		ALIGNMENT_LEFT,
-		ALIGNMENT_CENTER,
-		ALIGNMENT_RIGHT,
-	};
-
-private:
-	int first_tab_cache = 0;
-	int tabs_ofs_cache = 0;
-	int last_tab_cache = 0;
-	int current = 0;
-	int previous = 0;
+	TabBar *tab_bar;
 	bool tabs_visible = true;
 	bool all_tabs_in_front = false;
-	bool buttons_visible_cache = false;
 	bool menu_hovered = false;
-	int highlight_arrow = -1;
-	AlignmentMode alignment = ALIGNMENT_CENTER;
-	int _get_top_margin() const;
 	mutable ObjectID popup_obj_id;
 	bool drag_to_rearrange_enabled = false;
 	bool use_hidden_tabs_for_min_size = false;
-	int tabs_rearrange_group = -1;
+	bool theme_changing = false;
 
-	Vector<Ref<TextLine>> text_buf;
-	Vector<Control *> _get_tabs() const;
-	int _get_tab_width(int p_index) const;
-	bool _theme_changing = false;
+	int _get_top_margin() const;
+	Vector<Control *> _get_tab_controls() const;
 	void _on_theme_changed();
 	void _repaint();
+	void _update_margins();
 	void _on_mouse_exited();
-	void _update_current_tab();
-	void _draw_tab(Ref<StyleBox> &p_tab_style, Color &p_font_color, int p_index, float p_x);
-	void _refresh_texts();
+	void _on_tab_changed(int p_tab);
+	void _on_tab_selected(int p_tab);
+
+	Variant _get_drag_data_fw(const Point2 &p_point, Control *p_from_control);
+	bool _can_drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from_control) const;
+	void _drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from_control);
 
 protected:
 	void _child_renamed_callback();
@@ -81,17 +67,17 @@ protected:
 	virtual void add_child_notify(Node *p_child) override;
 	virtual void move_child_notify(Node *p_child) override;
 	virtual void remove_child_notify(Node *p_child) override;
+	static void _bind_methods();
 
-	Variant get_drag_data(const Point2 &p_point) override;
-	bool can_drop_data(const Point2 &p_point, const Variant &p_data) const override;
-	void drop_data(const Point2 &p_point, const Variant &p_data) override;
+public:
 	int get_tab_idx_at_point(const Point2 &p_point) const;
+	int get_tab_idx_from_control(Control *p_child) const;
 
-	static void _bind_methods();
+	void set_tab_alignment(TabBar::AlignmentMode p_alignment);
+	TabBar::AlignmentMode get_tab_alignment() const;
 
-public:
-	void set_tab_alignment(AlignmentMode p_alignment);
-	AlignmentMode get_tab_alignment() const;
+	void set_clip_tabs(bool p_clip_tabs);
+	bool get_clip_tabs() const;
 
 	void set_tabs_visible(bool p_visible);
 	bool are_tabs_visible() const;
@@ -106,10 +92,10 @@ public:
 	Ref<Texture2D> get_tab_icon(int p_tab) const;
 
 	void set_tab_disabled(int p_tab, bool p_disabled);
-	bool get_tab_disabled(int p_tab) const;
+	bool is_tab_disabled(int p_tab) const;
 
 	void set_tab_hidden(int p_tab, bool p_hidden);
-	bool get_tab_hidden(int p_tab) const;
+	bool is_tab_hidden(int p_tab) const;
 
 	int get_tab_count() const;
 	void set_current_tab(int p_current);
@@ -139,6 +125,4 @@ public:
 	TabContainer();
 };
 
-VARIANT_ENUM_CAST(TabContainer::AlignmentMode);
-
 #endif // TAB_CONTAINER_H