[3.x] Add type icons to editor docs' hierarchy

Backport of #64847 and #65248

editor/editor_help.cpp

@@ -212,6 +212,27 @@ void EditorHelp::_add_type(const String &p_type, const String &p_enum) {
 	class_desc->pop();
 }
 
+void EditorHelp::_add_type_icon(const String &p_type, int p_size) {
+	Ref<Texture> icon;
+	if (has_icon(p_type, "EditorIcons")) {
+		icon = get_icon(p_type, "EditorIcons");
+	} else if (ClassDB::class_exists(p_type) && ClassDB::is_parent_class(p_type, "Object")) {
+		icon = get_icon("Object", "EditorIcons");
+	} else {
+		icon = get_icon("ArrowRight", "EditorIcons");
+	}
+
+	Vector2i size = Vector2i(icon->get_width(), icon->get_height());
+	if (p_size > 0) {
+		// Ensures icon scales proportionally on both axis, based on icon height.
+		float ratio = p_size / float(size.height);
+		size.width *= ratio;
+		size.height *= ratio;
+	}
+
+	class_desc->add_image(icon, size.width, size.height);
+}
+
 String EditorHelp::_fix_constant(const String &p_constant) const {
 	if (p_constant.strip_edges() == "4294967295") {
 		return "0xFFFFFFFF";
@@ -364,6 +385,8 @@ void EditorHelp::_update_doc() {
 	class_desc->push_font(doc_title_font);
 	class_desc->push_color(title_color);
 	class_desc->add_text(TTR("Class:") + " ");
+	_add_type_icon(edited_class, doc_title_font->get_height());
+	class_desc->add_text(" ");
 	class_desc->push_color(headline_color);
 	_add_text(edited_class);
 	class_desc->pop();
@@ -371,6 +394,8 @@ void EditorHelp::_update_doc() {
 	class_desc->pop();
 	class_desc->add_newline();
 
+	const String non_breaking_space = String::chr(160);
+
 	// Inheritance tree
 
 	// Ascendents
@@ -382,6 +407,8 @@ void EditorHelp::_update_doc() {
 		String inherits = cd.inherits;
 
 		while (inherits != "") {
+			_add_type_icon(inherits);
+			class_desc->add_text(non_breaking_space); // Otherwise icon borrows hyperlink from _add_type().
 			_add_type(inherits);
 
 			inherits = doc->class_list[inherits].inherits;
@@ -413,7 +440,8 @@ void EditorHelp::_update_doc() {
 				if (prev) {
 					class_desc->add_text(" , ");
 				}
-
+				_add_type_icon(E->get().name);
+				class_desc->add_text(non_breaking_space); // Otherwise icon borrows hyperlink from _add_type().
 				_add_type(E->get().name);
 				prev = true;
 			}

editor/editor_help.h

@@ -142,6 +142,7 @@ class EditorHelp : public VBoxContainer {
 
 	//void _button_pressed(int p_idx);
 	void _add_type(const String &p_type, const String &p_enum = String());
+	void _add_type_icon(const String &p_type, int p_size = 0);
 	void _add_method(const DocData::MethodDoc &p_method, bool p_overview = true);
 
 	void _add_bulletpoint();