Dynamic infinite 3D grid

Well, infinite for all intents and purposes.

4 files changed, 173 insertions, 63 deletions

diff --git a/editor/editor_settings.cpp b/editor/editor_settings.cpp
index a16605ab44..5f293f1fb3 100644
--- a/editor/editor_settings.cpp
+++ b/editor/editor_settings.cpp
@@ -503,17 +503,38 @@ void EditorSettings::_load_defaults(Ref<ConfigFile> p_extra_config) {
 	_initial_set("editors/grid_map/pick_distance", 5000.0);
 
 	// 3D
-	_initial_set("editors/3d/primary_grid_color", Color(0.56, 0.56, 0.56));
-	hints["editors/3d/primary_grid_color"] = PropertyInfo(Variant::COLOR, "editors/3d/primary_grid_color", PROPERTY_HINT_COLOR_NO_ALPHA, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_RESTART_IF_CHANGED);
+	_initial_set("editors/3d/primary_grid_color", Color(0.56, 0.56, 0.56, 0.5));
+	hints["editors/3d/primary_grid_color"] = PropertyInfo(Variant::COLOR, "editors/3d/primary_grid_color", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT);
 
-	_initial_set("editors/3d/secondary_grid_color", Color(0.38, 0.38, 0.38));
-	hints["editors/3d/secondary_grid_color"] = PropertyInfo(Variant::COLOR, "editors/3d/secondary_grid_color", PROPERTY_HINT_COLOR_NO_ALPHA, "", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_RESTART_IF_CHANGED);
-
-	_initial_set("editors/3d/grid_size", 50);
-	hints["editors/3d/grid_size"] = PropertyInfo(Variant::INT, "editors/3d/grid_size", PROPERTY_HINT_RANGE, "1,500,1", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_RESTART_IF_CHANGED);
+	_initial_set("editors/3d/secondary_grid_color", Color(0.38, 0.38, 0.38, 0.5));
+	hints["editors/3d/secondary_grid_color"] = PropertyInfo(Variant::COLOR, "editors/3d/secondary_grid_color", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_DEFAULT);
 
+	// If a line is a multiple of this, it uses the primary grid color.
 	_initial_set("editors/3d/primary_grid_steps", 10);
-	hints["editors/3d/primary_grid_steps"] = PropertyInfo(Variant::INT, "editors/3d/primary_grid_steps", PROPERTY_HINT_RANGE, "1,100,1", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_RESTART_IF_CHANGED);
+	hints["editors/3d/primary_grid_steps"] = PropertyInfo(Variant::INT, "editors/3d/primary_grid_steps", PROPERTY_HINT_RANGE, "1,100,1", PROPERTY_USAGE_DEFAULT);
+
+	// At 1000, the grid mostly looks like it has no edge.
+	_initial_set("editors/3d/grid_size", 200);
+	hints["editors/3d/grid_size"] = PropertyInfo(Variant::INT, "editors/3d/grid_size", PROPERTY_HINT_RANGE, "1,2000,1", PROPERTY_USAGE_DEFAULT);
+
+	// Default largest grid size is 100m, 10^2 (primary grid lines are 1km apart when primary_grid_steps is 10).
+	_initial_set("editors/3d/grid_division_level_max", 2);
+	// Higher values produce graphical artifacts when far away unless View Z-Far
+	// is increased significantly more than it really should need to be.
+	hints["editors/3d/grid_division_level_max"] = PropertyInfo(Variant::INT, "editors/3d/grid_division_level_max", PROPERTY_HINT_RANGE, "-1,3,1", PROPERTY_USAGE_DEFAULT);
+
+	// Default smallest grid size is 1cm, 10^-2.
+	_initial_set("editors/3d/grid_division_level_min", -2);
+	// Lower values produce graphical artifacts regardless of view clipping planes, so limit to -2 as a lower bound.
+	hints["editors/3d/grid_division_level_min"] = PropertyInfo(Variant::INT, "editors/3d/grid_division_level_min", PROPERTY_HINT_RANGE, "-2,2,1", PROPERTY_USAGE_DEFAULT);
+
+	// -0.2 seems like a sensible default. -1.0 gives Blender-like behavior, 0.5 gives huge grids.
+	_initial_set("editors/3d/grid_division_level_bias", -0.2);
+	hints["editors/3d/grid_division_level_bias"] = PropertyInfo(Variant::FLOAT, "editors/3d/grid_division_level_bias", PROPERTY_HINT_RANGE, "-1.0,0.5,0.1", PROPERTY_USAGE_DEFAULT);
+
+	_initial_set("editors/3d/grid_xz_plane", true);
+	_initial_set("editors/3d/grid_xy_plane", false);
+	_initial_set("editors/3d/grid_yz_plane", false);
 
 	_initial_set("editors/3d/default_fov", 70.0);
 	_initial_set("editors/3d/default_z_near", 0.05);
diff --git a/editor/plugins/node_3d_editor_plugin.cpp b/editor/plugins/node_3d_editor_plugin.cpp
index 3c12022854..8466ee86e5 100644
--- a/editor/plugins/node_3d_editor_plugin.cpp
+++ b/editor/plugins/node_3d_editor_plugin.cpp
@@ -328,17 +328,13 @@ void Node3DEditorViewport::_update_camera(float p_interp_delta) {
 	//-------
 	// Apply camera transform
 
-	float tolerance = 0.001;
+	real_t tolerance = 0.001;
 	bool equal = true;
-	if (Math::abs(old_camera_cursor.x_rot - camera_cursor.x_rot) > tolerance || Math::abs(old_camera_cursor.y_rot - camera_cursor.y_rot) > tolerance) {
+	if (!Math::is_equal_approx(old_camera_cursor.x_rot, camera_cursor.x_rot, tolerance) || !Math::is_equal_approx(old_camera_cursor.y_rot, camera_cursor.y_rot, tolerance)) {
 		equal = false;
-	}
-
-	if (equal && old_camera_cursor.pos.distance_squared_to(camera_cursor.pos) > tolerance * tolerance) {
+	} else if (!old_camera_cursor.pos.is_equal_approx(camera_cursor.pos)) {
 		equal = false;
-	}
-
-	if (equal && Math::abs(old_camera_cursor.distance - camera_cursor.distance) > tolerance) {
+	} else if (!Math::is_equal_approx(old_camera_cursor.distance, camera_cursor.distance, tolerance)) {
 		equal = false;
 	}
 
@@ -356,6 +352,7 @@ void Node3DEditorViewport::_update_camera(float p_interp_delta) {
 		update_transform_gizmo_view();
 		rotation_control->update();
 	}
+	spatial_editor->update_grid();
 }
 
 Transform Node3DEditorViewport::to_camera_transform(const Cursor &p_cursor) const {
@@ -4929,8 +4926,10 @@ void Node3DEditor::_menu_item_pressed(int p_option) {
 
 			for (int i = 0; i < 3; ++i) {
 				if (grid_enable[i]) {
-					RenderingServer::get_singleton()->instance_set_visible(grid_instance[i], grid_enabled);
 					grid_visible[i] = grid_enabled;
+					if (grid_instance[i].is_valid()) {
+						RenderingServer::get_singleton()->instance_set_visible(grid_instance[i], grid_enabled);
+					}
 				}
 			}
 
@@ -5054,6 +5053,7 @@ void Node3DEditor::_init_indicators() {
 		indicator_mat->set_shading_mode(StandardMaterial3D::SHADING_MODE_UNSHADED);
 		indicator_mat->set_flag(StandardMaterial3D::FLAG_ALBEDO_FROM_VERTEX_COLOR, true);
 		indicator_mat->set_flag(StandardMaterial3D::FLAG_SRGB_VERTEX_COLOR, true);
+		indicator_mat->set_transparency(StandardMaterial3D::Transparency::TRANSPARENCY_ALPHA_DEPTH_PRE_PASS);
 
 		Vector<Color> origin_colors;
 		Vector<Vector3> origin_points;
@@ -5082,12 +5082,27 @@ void Node3DEditor::_init_indicators() {
 
 			origin_colors.push_back(origin_color);
 			origin_colors.push_back(origin_color);
-			origin_points.push_back(axis * 4096);
-			origin_points.push_back(axis * -4096);
-		}
-
-		grid_enable[1] = true;
-		grid_visible[1] = true;
+			origin_colors.push_back(origin_color);
+			origin_colors.push_back(origin_color);
+			origin_colors.push_back(origin_color);
+			origin_colors.push_back(origin_color);
+			// To both allow having a large origin size and avoid jitter
+			// at small scales, we should segment the line into pieces.
+			// 3 pieces seems to do the trick, and let's use powers of 2.
+			origin_points.push_back(axis * 1048576);
+			origin_points.push_back(axis * 1024);
+			origin_points.push_back(axis * 1024);
+			origin_points.push_back(axis * -1024);
+			origin_points.push_back(axis * -1024);
+			origin_points.push_back(axis * -1048576);
+		}
+
+		grid_enable[0] = EditorSettings::get_singleton()->get("editors/3d/grid_xy_plane");
+		grid_enable[1] = EditorSettings::get_singleton()->get("editors/3d/grid_yz_plane");
+		grid_enable[2] = EditorSettings::get_singleton()->get("editors/3d/grid_xz_plane");
+		grid_visible[0] = grid_enable[0];
+		grid_visible[1] = grid_enable[1];
+		grid_visible[2] = grid_enable[2];
 
 		_init_grid();
 
@@ -5418,6 +5433,15 @@ void Node3DEditor::_update_gizmos_menu_theme() {
 }
 
 void Node3DEditor::_init_grid() {
+	if (!grid_enabled) {
+		return;
+	}
+	Camera3D *camera = get_editor_viewport(0)->camera;
+	Vector3 camera_position = camera->get_translation();
+	if (camera_position == Vector3()) {
+		return; // Camera3D is invalid, don't draw the grid.
+	}
+
 	Vector<Color> grid_colors[3];
 	Vector<Vector3> grid_points[3];
 
@@ -5426,52 +5450,111 @@ void Node3DEditor::_init_grid() {
 	int grid_size = EditorSettings::get_singleton()->get("editors/3d/grid_size");
 	int primary_grid_steps = EditorSettings::get_singleton()->get("editors/3d/primary_grid_steps");
 
-	for (int i = 0; i < 3; i++) {
-		Vector3 axis;
-		axis[i] = 1;
-		Vector3 axis_n1;
-		axis_n1[(i + 1) % 3] = 1;
-		Vector3 axis_n2;
-		axis_n2[(i + 2) % 3] = 1;
-
-		for (int j = -grid_size; j <= grid_size; j++) {
-			Vector3 p1 = axis_n1 * j + axis_n2 * -grid_size;
-			Vector3 p1_dest = p1 * (-axis_n2 + axis_n1);
-			Vector3 p2 = axis_n2 * j + axis_n1 * -grid_size;
-			Vector3 p2_dest = p2 * (-axis_n1 + axis_n2);
-
-			Color line_color = secondary_grid_color;
-			if (origin_enabled && j == 0) {
-				// Don't draw the center lines of the grid if the origin is enabled
-				// The origin would overlap the grid lines in this case, causing flickering
-				continue;
-			} else if (j % primary_grid_steps == 0) {
-				line_color = primary_grid_color;
+	// Which grid planes are enabled? Which should we generate?
+	grid_enable[0] = grid_visible[0] = EditorSettings::get_singleton()->get("editors/3d/grid_xy_plane");
+	grid_enable[1] = grid_visible[1] = EditorSettings::get_singleton()->get("editors/3d/grid_yz_plane");
+	grid_enable[2] = grid_visible[2] = EditorSettings::get_singleton()->get("editors/3d/grid_xz_plane");
+
+	// Offsets division_level for bigger or smaller grids.
+	// Default value is -0.2. -1.0 gives Blender-like behavior, 0.5 gives huge grids.
+	real_t division_level_bias = EditorSettings::get_singleton()->get("editors/3d/grid_division_level_bias");
+	// Default largest grid size is 100m, 10^2 (default value is 2).
+	int division_level_max = EditorSettings::get_singleton()->get("editors/3d/grid_division_level_max");
+	// Default smallest grid size is 1cm, 10^-2 (default value is -2).
+	int division_level_min = EditorSettings::get_singleton()->get("editors/3d/grid_division_level_min");
+	ERR_FAIL_COND_MSG(division_level_max < division_level_min, "The 3D grid's maximum division level cannot be lower than its minimum division level.");
+
+	if (primary_grid_steps != 10) { // Log10 of 10 is 1.
+		// Change of base rule, divide by ln(10).
+		real_t div = Math::log((real_t)primary_grid_steps) / (real_t)2.302585092994045901094;
+		// Trucation (towards zero) is intentional.
+		division_level_max = (int)(division_level_max / div);
+		division_level_min = (int)(division_level_min / div);
+	}
+
+	for (int a = 0; a < 3; a++) {
+		if (!grid_enable[a]) {
+			continue; // If this grid plane is disabled, skip generation.
+		}
+		int b = (a + 1) % 3;
+		int c = (a + 2) % 3;
+
+		real_t division_level = Math::log(Math::abs(camera_position[c])) / Math::log((double)primary_grid_steps) + division_level_bias;
+		division_level = CLAMP(division_level, division_level_min, division_level_max);
+		real_t division_level_floored = Math::floor(division_level);
+		real_t division_level_decimals = division_level - division_level_floored;
+
+		real_t small_step_size = Math::pow(primary_grid_steps, division_level_floored);
+		real_t large_step_size = small_step_size * primary_grid_steps;
+		real_t center_a = large_step_size * (int)(camera_position[a] / large_step_size);
+		real_t center_b = large_step_size * (int)(camera_position[b] / large_step_size);
+
+		real_t bgn_a = center_a - grid_size * small_step_size;
+		real_t end_a = center_a + grid_size * small_step_size;
+		real_t bgn_b = center_b - grid_size * small_step_size;
+		real_t end_b = center_b + grid_size * small_step_size;
+
+		// In each iteration of this loop, draw one line in each direction (so two lines per loop, in each if statement).
+		for (int i = -grid_size; i <= grid_size; i++) {
+			Color line_color;
+			// Is this a primary line? Set the appropriate color.
+			if (i % primary_grid_steps == 0) {
+				line_color = primary_grid_color.lerp(secondary_grid_color, division_level_decimals);
+			} else {
+				line_color = secondary_grid_color;
+				line_color.a = line_color.a * (1 - division_level_decimals);
+			}
+			// Makes lines farther from the center fade out.
+			// Due to limitations of lines, any that come near the camera have full opacity always.
+			// This should eventually be replaced by some kind of "distance fade" system, outside of this function.
+			// But the effect is still somewhat convincing...
+			line_color.a *= 1 - (1 - division_level_decimals * 0.9) * (Math::abs(i / (float)grid_size));
+
+			real_t position_a = center_a + i * small_step_size;
+			real_t position_b = center_b + i * small_step_size;
+
+			// Don't draw lines over the origin if it's enabled.
+			if (!(origin_enabled && Math::is_zero_approx(position_a))) {
+				Vector3 line_bgn = Vector3();
+				Vector3 line_end = Vector3();
+				line_bgn[a] = position_a;
+				line_end[a] = position_a;
+				line_bgn[b] = bgn_b;
+				line_end[b] = end_b;
+				grid_points[c].push_back(line_bgn);
+				grid_points[c].push_back(line_end);
+				grid_colors[c].push_back(line_color);
+				grid_colors[c].push_back(line_color);
 			}
 
-			grid_points[i].push_back(p1);
-			grid_points[i].push_back(p1_dest);
-			grid_colors[i].push_back(line_color);
-			grid_colors[i].push_back(line_color);
-
-			grid_points[i].push_back(p2);
-			grid_points[i].push_back(p2_dest);
-			grid_colors[i].push_back(line_color);
-			grid_colors[i].push_back(line_color);
+			if (!(origin_enabled && Math::is_zero_approx(position_b))) {
+				Vector3 line_bgn = Vector3();
+				Vector3 line_end = Vector3();
+				line_bgn[b] = position_b;
+				line_end[b] = position_b;
+				line_bgn[a] = bgn_a;
+				line_end[a] = end_a;
+				grid_points[c].push_back(line_bgn);
+				grid_points[c].push_back(line_end);
+				grid_colors[c].push_back(line_color);
+				grid_colors[c].push_back(line_color);
+			}
 		}
 
-		grid[i] = RenderingServer::get_singleton()->mesh_create();
+		// Create a mesh from the pushed vector points and colors.
+		grid[c] = RenderingServer::get_singleton()->mesh_create();
 		Array d;
 		d.resize(RS::ARRAY_MAX);
-		d[RenderingServer::ARRAY_VERTEX] = grid_points[i];
-		d[RenderingServer::ARRAY_COLOR] = grid_colors[i];
-		RenderingServer::get_singleton()->mesh_add_surface_from_arrays(grid[i], RenderingServer::PRIMITIVE_LINES, d);
-		RenderingServer::get_singleton()->mesh_surface_set_material(grid[i], 0, indicator_mat->get_rid());
-		grid_instance[i] = RenderingServer::get_singleton()->instance_create2(grid[i], get_tree()->get_root()->get_world_3d()->get_scenario());
+		d[RenderingServer::ARRAY_VERTEX] = grid_points[c];
+		d[RenderingServer::ARRAY_COLOR] = grid_colors[c];
+		RenderingServer::get_singleton()->mesh_add_surface_from_arrays(grid[c], RenderingServer::PRIMITIVE_LINES, d);
+		RenderingServer::get_singleton()->mesh_surface_set_material(grid[c], 0, indicator_mat->get_rid());
+		grid_instance[c] = RenderingServer::get_singleton()->instance_create2(grid[c], get_tree()->get_root()->get_world_3d()->get_scenario());
 
-		RenderingServer::get_singleton()->instance_set_visible(grid_instance[i], grid_visible[i]);
-		RenderingServer::get_singleton()->instance_geometry_set_cast_shadows_setting(grid_instance[i], RS::SHADOW_CASTING_SETTING_OFF);
-		RS::get_singleton()->instance_set_layer_mask(grid_instance[i], 1 << Node3DEditorViewport::GIZMO_GRID_LAYER);
+		// Yes, the end of this line is supposed to be a.
+		RenderingServer::get_singleton()->instance_set_visible(grid_instance[c], grid_visible[a]);
+		RenderingServer::get_singleton()->instance_geometry_set_cast_shadows_setting(grid_instance[c], RS::SHADOW_CASTING_SETTING_OFF);
+		RS::get_singleton()->instance_set_layer_mask(grid_instance[c], 1 << Node3DEditorViewport::GIZMO_GRID_LAYER);
 	}
 }
 
@@ -5489,6 +5572,11 @@ void Node3DEditor::_finish_grid() {
 	}
 }
 
+void Node3DEditor::update_grid() {
+	_finish_grid();
+	_init_grid();
+}
+
 bool Node3DEditor::is_any_freelook_active() const {
 	for (unsigned int i = 0; i < VIEWPORTS_COUNT; ++i) {
 		if (viewports[i]->is_freelook_active()) {
diff --git a/editor/plugins/node_3d_editor_plugin.h b/editor/plugins/node_3d_editor_plugin.h
index 3d92e7e7e1..32b087c372 100644
--- a/editor/plugins/node_3d_editor_plugin.h
+++ b/editor/plugins/node_3d_editor_plugin.h
@@ -766,6 +766,7 @@ public:
 	Ref<ArrayMesh> get_scale_gizmo(int idx) const { return scale_gizmo[idx]; }
 	Ref<ArrayMesh> get_scale_plane_gizmo(int idx) const { return scale_plane_gizmo[idx]; }
 
+	void update_grid();
 	void update_transform_gizmo();
 	void update_all_gizmos(Node *p_node = nullptr);
 	void snap_selected_nodes_to_floor();
diff --git a/main/tests/test_math.cpp b/main/tests/test_math.cpp
index 11aa164709..9e159798bb 100644
--- a/main/tests/test_math.cpp
+++ b/main/tests/test_math.cpp
@@ -482,7 +482,7 @@ MainLoop *test() {
 		float gb = (rgbe >> 9) & 0x1ff;
 		float bb = (rgbe >> 18) & 0x1ff;
 		float eb = (rgbe >> 27);
-		float mb = Math::pow(2, eb - 15.0 - 9.0);
+		float mb = Math::pow(2.0, eb - 15.0 - 9.0);
 		float rd = rb * mb;
 		float gd = gb * mb;
 		float bd = bb * mb;