Implement a system to contextualize global themes

editor/editor_node.h

@@ -295,7 +295,6 @@ class EditorNode : public Node {
 	bool is_main_screen_editing = false;
 
 	PanelContainer *scene_root_parent = nullptr;
-	Control *theme_base = nullptr;
 	Control *gui_base = nullptr;
 	VBoxContainer *main_vbox = nullptr;
 	OptionButton *renderer = nullptr;
@@ -525,6 +524,7 @@ class EditorNode : public Node {
 	static void _resource_saved(Ref<Resource> p_resource, const String &p_path);
 	static void _resource_loaded(Ref<Resource> p_resource, const String &p_path);
 
+	void _update_theme(bool p_skip_creation = false);
 	void _build_icon_type_cache();
 	void _enable_pending_addons();
 
@@ -851,6 +851,8 @@ class EditorNode : public Node {
 	void stop_child_process(OS::ProcessID p_pid);
 
 	Ref<Theme> get_editor_theme() const { return theme; }
+	void update_preview_themes(int p_mode);
+
 	Ref<Script> get_object_custom_type_base(const Object *p_object) const;
 	StringName get_object_custom_type_name(const Object *p_object) const;
 	Ref<Texture2D> get_object_icon(const Object *p_object, const String &p_fallback = "Object");
@@ -867,7 +869,6 @@ class EditorNode : public Node {
 	Error export_preset(const String &p_preset, const String &p_path, bool p_debug, bool p_pack_only);
 
 	Control *get_gui_base() { return gui_base; }
-	Control *get_theme_base() { return gui_base->get_parent_control(); }
 
 	void save_scene_to_path(String p_file, bool p_with_preview = true) {
 		if (p_with_preview) {

editor/editor_resource_preview.cpp

@@ -40,6 +40,7 @@
 #include "editor/editor_paths.h"
 #include "editor/editor_scale.h"
 #include "editor/editor_settings.h"
+#include "editor/editor_string_names.h"
 #include "scene/resources/image_texture.h"
 
 bool EditorResourcePreviewGenerator::handles(const String &p_type) const {
@@ -341,7 +342,8 @@ void EditorResourcePreview::_thread() {
 
 void EditorResourcePreview::_update_thumbnail_sizes() {
 	if (small_thumbnail_size == -1) {
-		small_thumbnail_size = EditorNode::get_singleton()->get_theme_base()->get_editor_theme_icon(SNAME("Object"))->get_width(); // Kind of a workaround to retrieve the default icon size
+		// Kind of a workaround to retrieve the default icon size.
+		small_thumbnail_size = EditorNode::get_singleton()->get_editor_theme()->get_icon(SNAME("Object"), EditorStringName(EditorIcons))->get_width();
 	}
 }
 

editor/plugins/canvas_item_editor_plugin.cpp

@@ -1034,6 +1034,22 @@ void CanvasItemEditor::_on_grid_menu_id_pressed(int p_id) {
 	viewport->queue_redraw();
 }
 
+void CanvasItemEditor::_switch_theme_preview(int p_mode) {
+	view_menu->get_popup()->hide();
+
+	if (theme_preview == p_mode) {
+		return;
+	}
+	theme_preview = (ThemePreviewMode)p_mode;
+	EditorSettings::get_singleton()->set_project_metadata("2d_editor", "theme_preview", theme_preview);
+
+	for (int i = 0; i < THEME_PREVIEW_MAX; i++) {
+		theme_menu->set_item_checked(i, i == theme_preview);
+	}
+
+	EditorNode::get_singleton()->update_preview_themes(theme_preview);
+}
+
 bool CanvasItemEditor::_gui_input_rulers_and_guides(const Ref<InputEvent> &p_event) {
 	EditorUndoRedoManager *undo_redo = EditorUndoRedoManager::get_singleton();
 	Ref<InputEventMouseButton> b = p_event;
@@ -5322,6 +5338,20 @@ CanvasItemEditor::CanvasItemEditor() {
 	p->add_separator();
 	p->add_check_shortcut(ED_SHORTCUT("canvas_item_editor/preview_canvas_scale", TTR("Preview Canvas Scale")), PREVIEW_CANVAS_SCALE);
 
+	theme_menu = memnew(PopupMenu);
+	theme_menu->connect("id_pressed", callable_mp(this, &CanvasItemEditor::_switch_theme_preview));
+	theme_menu->set_name("ThemeMenu");
+	theme_menu->add_radio_check_item(TTR("Project theme"), THEME_PREVIEW_PROJECT);
+	theme_menu->add_radio_check_item(TTR("Editor theme"), THEME_PREVIEW_EDITOR);
+	theme_menu->add_radio_check_item(TTR("Default theme"), THEME_PREVIEW_DEFAULT);
+	p->add_child(theme_menu);
+	p->add_submenu_item(TTR("Preview Theme"), "ThemeMenu");
+
+	theme_preview = (ThemePreviewMode)(int)EditorSettings::get_singleton()->get_project_metadata("2d_editor", "theme_preview", THEME_PREVIEW_PROJECT);
+	for (int i = 0; i < THEME_PREVIEW_MAX; i++) {
+		theme_menu->set_item_checked(i, i == theme_preview);
+	}
+
 	main_menu_hbox->add_child(memnew(VSeparator));
 
 	// Contextual toolbars.

editor/plugins/canvas_item_editor_plugin.h

@@ -325,6 +325,7 @@ class CanvasItemEditor : public VBoxContainer {
 	Button *override_camera_button = nullptr;
 	MenuButton *view_menu = nullptr;
 	PopupMenu *grid_menu = nullptr;
+	PopupMenu *theme_menu = nullptr;
 	HBoxContainer *animation_hb = nullptr;
 	MenuButton *animation_menu = nullptr;
 
@@ -404,6 +405,19 @@ class CanvasItemEditor : public VBoxContainer {
 	void _prepare_grid_menu();
 	void _on_grid_menu_id_pressed(int p_id);
 
+public:
+	enum ThemePreviewMode {
+		THEME_PREVIEW_PROJECT,
+		THEME_PREVIEW_EDITOR,
+		THEME_PREVIEW_DEFAULT,
+
+		THEME_PREVIEW_MAX // The number of options for enumerating.
+	};
+
+private:
+	ThemePreviewMode theme_preview = THEME_PREVIEW_PROJECT;
+	void _switch_theme_preview(int p_mode);
+
 	List<CanvasItem *> _get_edited_canvas_items(bool retrieve_locked = false, bool remove_canvas_item_if_parent_in_selection = true) const;
 	Rect2 _get_encompassing_rect_from_list(List<CanvasItem *> p_list);
 	void _expand_encompassing_rect_using_children(Rect2 &r_rect, const Node *p_node, bool &r_first, const Transform2D &p_parent_xform = Transform2D(), const Transform2D &p_canvas_xform = Transform2D(), bool include_locked_nodes = true);
@@ -558,6 +572,8 @@ class CanvasItemEditor : public VBoxContainer {
 
 	virtual CursorShape get_cursor_shape(const Point2 &p_pos) const override;
 
+	ThemePreviewMode get_theme_preview() const { return theme_preview; }
+
 	EditorSelection *editor_selection = nullptr;
 
 	CanvasItemEditor();

editor/plugins/script_editor_plugin.cpp

@@ -1612,6 +1612,8 @@ void ScriptEditor::_notification(int p_what) {
 		case NOTIFICATION_TRANSLATION_CHANGED:
 		case NOTIFICATION_LAYOUT_DIRECTION_CHANGED:
 		case NOTIFICATION_THEME_CHANGED: {
+			tab_container->add_theme_style_override("panel", get_theme_stylebox(SNAME("ScriptEditor"), EditorStringName(EditorStyles)));
+
 			help_search->set_icon(get_editor_theme_icon(SNAME("HelpSearch")));
 			site_search->set_icon(get_editor_theme_icon(SNAME("ExternalLink")));
 
@@ -1628,7 +1630,7 @@ void ScriptEditor::_notification(int p_what) {
 			filter_scripts->set_right_icon(get_editor_theme_icon(SNAME("Search")));
 			filter_methods->set_right_icon(get_editor_theme_icon(SNAME("Search")));
 
-			filename->add_theme_style_override("normal", EditorNode::get_singleton()->get_gui_base()->get_theme_stylebox(SNAME("normal"), SNAME("LineEdit")));
+			filename->add_theme_style_override("normal", get_theme_stylebox(SNAME("normal"), SNAME("LineEdit")));
 
 			recent_scripts->reset_size();
 
@@ -1639,6 +1641,9 @@ void ScriptEditor::_notification(int p_what) {
 		} break;
 
 		case NOTIFICATION_READY: {
+			// Can't set own styles in NOTIFICATION_THEME_CHANGED, so for now this will do.
+			add_theme_style_override("panel", get_theme_stylebox(SNAME("ScriptEditorPanel"), SNAME("EditorStyles")));
+
 			get_tree()->connect("tree_changed", callable_mp(this, &ScriptEditor::_tree_changed));
 			InspectorDock::get_singleton()->connect("request_help", callable_mp(this, &ScriptEditor::_help_class_open));
 			EditorNode::get_singleton()->connect("request_help_search", callable_mp(this, &ScriptEditor::_help_search));
@@ -4139,9 +4144,6 @@ ScriptEditor::ScriptEditor(WindowWrapper *p_wrapper) {
 
 	ScriptServer::edit_request_func = _open_script_request;
 
-	add_theme_style_override("panel", EditorNode::get_singleton()->get_gui_base()->get_theme_stylebox(SNAME("ScriptEditorPanel"), EditorStringName(EditorStyles)));
-	tab_container->add_theme_style_override("panel", EditorNode::get_singleton()->get_gui_base()->get_theme_stylebox(SNAME("ScriptEditor"), EditorStringName(EditorStyles)));
-
 	Ref<EditorJSONSyntaxHighlighter> json_syntax_highlighter;
 	json_syntax_highlighter.instantiate();
 	register_syntax_highlighter(json_syntax_highlighter);

editor/plugins/theme_editor_plugin.cpp

@@ -1217,7 +1217,7 @@ void ThemeItemEditorDialog::_dialog_about_to_show() {
 	import_default_theme_items->reset_item_tree();
 
 	import_editor_theme_items->set_edited_theme(edited_theme);
-	import_editor_theme_items->set_base_theme(EditorNode::get_singleton()->get_theme_base()->get_theme());
+	import_editor_theme_items->set_base_theme(EditorNode::get_singleton()->get_editor_theme());
 	import_editor_theme_items->reset_item_tree();
 
 	import_other_theme_items->set_edited_theme(edited_theme);

editor/plugins/theme_editor_preview.cpp

@@ -202,8 +202,14 @@ void ThemeEditorPreview::_notification(int p_what) {
 			}
 
 			connect("visibility_changed", callable_mp(this, &ThemeEditorPreview::_preview_visibility_changed));
-			[[fallthrough]];
-		}
+		} break;
+
+		case NOTIFICATION_READY: {
+			List<Ref<Theme>> preview_themes;
+			preview_themes.push_back(ThemeDB::get_singleton()->get_default_theme());
+			ThemeDB::get_singleton()->create_theme_context(preview_root, preview_themes);
+		} break;
+
 		case NOTIFICATION_THEME_CHANGED: {
 			picker_button->set_icon(get_editor_theme_icon(SNAME("ColorPick")));
 
@@ -247,9 +253,8 @@ ThemeEditorPreview::ThemeEditorPreview() {
 	preview_container = memnew(ScrollContainer);
 	preview_body->add_child(preview_container);
 
-	MarginContainer *preview_root = memnew(MarginContainer);
+	preview_root = memnew(MarginContainer);
 	preview_container->add_child(preview_root);
-	preview_root->set_theme(ThemeDB::get_singleton()->get_default_theme());
 	preview_root->set_clip_contents(true);
 	preview_root->set_custom_minimum_size(Size2(450, 0) * EDSCALE);
 	preview_root->set_v_size_flags(SIZE_EXPAND_FILL);

editor/plugins/theme_editor_preview.h

@@ -44,6 +44,7 @@ class ThemeEditorPreview : public VBoxContainer {
 	GDCLASS(ThemeEditorPreview, VBoxContainer);
 
 	ScrollContainer *preview_container = nullptr;
+	MarginContainer *preview_root = nullptr;
 	ColorRect *preview_bg = nullptr;
 	MarginContainer *preview_overlay = nullptr;
 	Control *picker_overlay = nullptr;

scene/3d/label_3d.cpp

@@ -780,42 +780,31 @@ Ref<Font> Label3D::_get_font_or_default() const {
 		return font_override;
 	}
 
-	// Check the project-defined Theme resource.
-	if (ThemeDB::get_singleton()->get_project_theme().is_valid()) {
-		List<StringName> theme_types;
-		ThemeDB::get_singleton()->get_project_theme()->get_type_dependencies(get_class_name(), StringName(), &theme_types);
+	StringName theme_name = "font";
+	List<StringName> theme_types;
+	ThemeDB::get_singleton()->get_native_type_dependencies(get_class_name(), &theme_types);
+
+	ThemeContext *global_context = ThemeDB::get_singleton()->get_default_theme_context();
+	for (const Ref<Theme> &theme : global_context->get_themes()) {
+		if (theme.is_null()) {
+			continue;
+		}
 
 		for (const StringName &E : theme_types) {
-			if (ThemeDB::get_singleton()->get_project_theme()->has_theme_item(Theme::DATA_TYPE_FONT, "font", E)) {
-				Ref<Font> f = ThemeDB::get_singleton()->get_project_theme()->get_theme_item(Theme::DATA_TYPE_FONT, "font", E);
-				if (f.is_valid()) {
-					theme_font = f;
-					theme_font->connect_changed(callable_mp(const_cast<Label3D *>(this), &Label3D::_font_changed));
-				}
-				return f;
+			if (!theme->has_font(theme_name, E)) {
+				continue;
 			}
-		}
-	}
 
-	// Lastly, fall back on the items defined in the default Theme, if they exist.
-	{
-		List<StringName> theme_types;
-		ThemeDB::get_singleton()->get_default_theme()->get_type_dependencies(get_class_name(), StringName(), &theme_types);
-
-		for (const StringName &E : theme_types) {
-			if (ThemeDB::get_singleton()->get_default_theme()->has_theme_item(Theme::DATA_TYPE_FONT, "font", E)) {
-				Ref<Font> f = ThemeDB::get_singleton()->get_default_theme()->get_theme_item(Theme::DATA_TYPE_FONT, "font", E);
-				if (f.is_valid()) {
-					theme_font = f;
-					theme_font->connect_changed(callable_mp(const_cast<Label3D *>(this), &Label3D::_font_changed));
-				}
-				return f;
+			Ref<Font> f = theme->get_font(theme_name, E);
+			if (f.is_valid()) {
+				theme_font = f;
+				theme_font->connect_changed(callable_mp(const_cast<Label3D *>(this), &Label3D::_font_changed));
 			}
+			return f;
 		}
 	}
 
-	// If they don't exist, use any type to return the default/empty value.
-	Ref<Font> f = ThemeDB::get_singleton()->get_default_theme()->get_theme_item(Theme::DATA_TYPE_FONT, "font", StringName());
+	Ref<Font> f = global_context->get_fallback_theme()->get_font(theme_name, StringName());
 	if (f.is_valid()) {
 		theme_font = f;
 		theme_font->connect_changed(callable_mp(const_cast<Label3D *>(this), &Label3D::_font_changed));

scene/gui/control.cpp

@@ -2465,6 +2465,11 @@ bool Control::has_theme_owner_node() const {
 	return data.theme_owner->has_owner_node();
 }
 
+void Control::set_theme_context(ThemeContext *p_context, bool p_propagate) {
+	ERR_MAIN_THREAD_GUARD;
+	data.theme_owner->set_owner_context(p_context, p_propagate);
+}
+
 void Control::set_theme(const Ref<Theme> &p_theme) {
 	ERR_MAIN_THREAD_GUARD;
 	if (data.theme == p_theme) {
@@ -3124,7 +3129,9 @@ void Control::_notification(int p_notification) {
 				notification(NOTIFICATION_TRANSLATION_CHANGED);
 			}
 #endif
-			notification(NOTIFICATION_THEME_CHANGED);
+
+			// Emits NOTIFICATION_THEME_CHANGED internally.
+			set_theme_context(ThemeDB::get_singleton()->get_nearest_theme_context(this));
 		} break;
 
 		case NOTIFICATION_POST_ENTER_TREE: {
@@ -3134,6 +3141,7 @@ void Control::_notification(int p_notification) {
 		} break;
 
 		case NOTIFICATION_EXIT_TREE: {
+			set_theme_context(nullptr, false);
 			release_focus();
 			get_viewport()->_gui_remove_control(this);
 		} break;
@@ -3632,7 +3640,7 @@ void Control::_bind_methods() {
 }
 
 Control::Control() {
-	data.theme_owner = memnew(ThemeOwner);
+	data.theme_owner = memnew(ThemeOwner(this));
 }
 
 Control::~Control() {

scene/gui/control.h

@@ -42,6 +42,7 @@ class Viewport;
 class Label;
 class Panel;
 class ThemeOwner;
+class ThemeContext;
 
 class Control : public CanvasItem {
 	GDCLASS(Control, CanvasItem);
@@ -553,6 +554,8 @@ class Control : public CanvasItem {
 	Node *get_theme_owner_node() const;
 	bool has_theme_owner_node() const;
 
+	void set_theme_context(ThemeContext *p_context, bool p_propagate = true);
+
 	void set_theme(const Ref<Theme> &p_theme);
 	Ref<Theme> get_theme() const;
 

scene/main/window.cpp

@@ -1269,7 +1269,9 @@ void Window::_notification(int p_what) {
 				notification(NOTIFICATION_TRANSLATION_CHANGED);
 			}
 #endif
-			notification(NOTIFICATION_THEME_CHANGED);
+
+			// Emits NOTIFICATION_THEME_CHANGED internally.
+			set_theme_context(ThemeDB::get_singleton()->get_nearest_theme_context(this));
 		} break;
 
 		case NOTIFICATION_READY: {
@@ -1313,6 +1315,8 @@ void Window::_notification(int p_what) {
 		} break;
 
 		case NOTIFICATION_EXIT_TREE: {
+			set_theme_context(nullptr, false);
+
 			if (transient) {
 				_clear_transient();
 			}
@@ -1889,6 +1893,11 @@ bool Window::has_theme_owner_node() const {
 	return theme_owner->has_owner_node();
 }
 
+void Window::set_theme_context(ThemeContext *p_context, bool p_propagate) {
+	ERR_MAIN_THREAD_GUARD;
+	theme_owner->set_owner_context(p_context, p_propagate);
+}
+
 void Window::set_theme(const Ref<Theme> &p_theme) {
 	ERR_MAIN_THREAD_GUARD;
 	if (theme == p_theme) {
@@ -2887,7 +2896,7 @@ Window::Window() {
 		max_size_used = max_size; // Update max_size_used.
 	}
 
-	theme_owner = memnew(ThemeOwner);
+	theme_owner = memnew(ThemeOwner(this));
 	RS::get_singleton()->viewport_set_update_mode(get_viewport_rid(), RS::VIEWPORT_UPDATE_DISABLED);
 }
 

scene/main/window.h

@@ -39,6 +39,7 @@ class Font;
 class Shortcut;
 class StyleBox;
 class ThemeOwner;
+class ThemeContext;
 
 class Window : public Viewport {
 	GDCLASS(Window, Viewport)
@@ -365,6 +366,8 @@ class Window : public Viewport {
 	Node *get_theme_owner_node() const;
 	bool has_theme_owner_node() const;
 
+	void set_theme_context(ThemeContext *p_context, bool p_propagate = true);
+
 	void set_theme(const Ref<Theme> &p_theme);
 	Ref<Theme> get_theme() const;