Apply clamp_to_embedder on parent resize and popup.

Fixes #75084.

The clamp_to_embedder setting was added in 8be16e0704,
but was not set on any of the in-editor dialogs.

This patch sets `clamp_to_embedder` on editor dialogs so they cannot be dragged out of the frame.
This also modifies `clamp_to_embedder` so a window is clamped to the bounds of an embedder when
it pops up and when the parent is resized.

editor/create_dialog.cpp

@@ -457,7 +457,7 @@ void CreateDialog::_notification(int p_what) {
 				search_box->call_deferred(SNAME("grab_focus")); // still not visible
 				search_box->select_all();
 			} else {
-				EditorSettings::get_singleton()->get_project_metadata("dialog_bounds", "create_new_node", Rect2(get_position(), get_size()));
+				EditorSettings::get_singleton()->set_project_metadata("dialog_bounds", "create_new_node", Rect2(get_position(), get_size()));
 			}
 		} break;
 
@@ -805,4 +805,5 @@ CreateDialog::CreateDialog() {
 
 	register_text_enter(search_box);
 	set_hide_on_ok(false);
+	set_clamp_to_embedder(true);
 }

editor/editor_help_search.cpp

@@ -182,6 +182,7 @@ void EditorHelpSearch::popup_dialog(const String &p_term) {
 
 EditorHelpSearch::EditorHelpSearch() {
 	set_hide_on_ok(false);
+	set_clamp_to_embedder(true);
 
 	set_title(TTR("Search Help"));
 

editor/editor_settings_dialog.cpp

@@ -698,6 +698,7 @@ void EditorSettingsDialog::_bind_methods() {
 
 EditorSettingsDialog::EditorSettingsDialog() {
 	set_title(TTR("Editor Settings"));
+	set_clamp_to_embedder(true);
 
 	tabs = memnew(TabContainer);
 	tabs->set_theme_type_variation("TabContainerOdd");

editor/export/project_export.cpp

@@ -1078,6 +1078,7 @@ void ProjectExportDialog::_bind_methods() {
 
 ProjectExportDialog::ProjectExportDialog() {
 	set_title(TTR("Export"));
+	set_clamp_to_embedder(true);
 
 	VBoxContainer *main_vb = memnew(VBoxContainer);
 	main_vb->connect("theme_changed", callable_mp(this, &ProjectExportDialog::_theme_changed));

editor/project_settings_editor.cpp

@@ -582,6 +582,7 @@ void ProjectSettingsEditor::_bind_methods() {
 ProjectSettingsEditor::ProjectSettingsEditor(EditorData *p_data) {
 	singleton = this;
 	set_title(TTR("Project Settings (project.godot)"));
+	set_clamp_to_embedder(true);
 
 	ps = ProjectSettings::get_singleton();
 	data = p_data;

scene/main/viewport.cpp

@@ -875,6 +875,17 @@ void Viewport::_set_size(const Size2i &p_size, const Size2i &p_size_2d_override,
 	}
 
 	emit_signal(SNAME("size_changed"));
+
+	Rect2i limit = get_visible_rect();
+	for (int i = 0; i < gui.sub_windows.size(); ++i) {
+		Window *sw = gui.sub_windows[i].window;
+		Rect2i rect = Rect2i(sw->position, sw->size);
+		Rect2i new_rect = sw->fit_rect_in_parent(rect, limit);
+		if (new_rect != rect) {
+			sw->set_position(new_rect.position);
+			sw->set_size(new_rect.size);
+		}
+	}
 }
 
 Size2i Viewport::_get_size() const {
@@ -2553,23 +2564,7 @@ bool Viewport::_sub_windows_forward_input(const Ref<InputEvent> &p_event) {
 				Rect2i new_rect(gui.subwindow_drag_pos + diff, gui.subwindow_focused->get_size());
 
 				if (gui.subwindow_focused->is_clamped_to_embedder()) {
-					Size2i limit = get_visible_rect().size;
-					if (new_rect.position.x + new_rect.size.x > limit.x) {
-						new_rect.position.x = limit.x - new_rect.size.x;
-					}
-					if (new_rect.position.y + new_rect.size.y > limit.y) {
-						new_rect.position.y = limit.y - new_rect.size.y;
-					}
-
-					if (new_rect.position.x < 0) {
-						new_rect.position.x = 0;
-					}
-
-					int title_height = gui.subwindow_focused->get_flag(Window::FLAG_BORDERLESS) ? 0 : gui.subwindow_focused->get_theme_constant(SNAME("title_height"));
-
-					if (new_rect.position.y < title_height) {
-						new_rect.position.y = title_height;
-					}
+					new_rect = gui.subwindow_focused->fit_rect_in_parent(new_rect, get_visible_rect());
 				}
 
 				gui.subwindow_focused->_rect_changed_callback(new_rect);

scene/main/window.cpp

@@ -1554,11 +1554,38 @@ void Window::popup(const Rect2i &p_screen_rect) {
 		ERR_PRINT(vformat("Window %d spawned at invalid position: %s.", get_window_id(), position));
 		set_position((parent_rect.size - size) / 2);
 	}
+	if (parent_rect != Rect2i() && is_clamped_to_embedder()) {
+		Rect2i new_rect = fit_rect_in_parent(Rect2i(position, size), parent_rect);
+		set_position(new_rect.position);
+		set_size(new_rect.size);
+	}
 
 	_post_popup();
 	notification(NOTIFICATION_POST_POPUP);
 }
 
+Rect2i Window::fit_rect_in_parent(Rect2i p_rect, const Rect2i &p_parent_rect) const {
+	Size2i limit = p_parent_rect.size;
+	if (p_rect.position.x + p_rect.size.x > limit.x) {
+		p_rect.position.x = limit.x - p_rect.size.x;
+	}
+	if (p_rect.position.y + p_rect.size.y > limit.y) {
+		p_rect.position.y = limit.y - p_rect.size.y;
+	}
+
+	if (p_rect.position.x < 0) {
+		p_rect.position.x = 0;
+	}
+
+	int title_height = get_flag(Window::FLAG_BORDERLESS) ? 0 : get_theme_constant(SNAME("title_height"));
+
+	if (p_rect.position.y < title_height) {
+		p_rect.position.y = title_height;
+	}
+
+	return p_rect;
+}
+
 Size2 Window::get_contents_minimum_size() const {
 	return _get_contents_minimum_size();
 }

scene/main/window.h

@@ -310,6 +310,7 @@ public:
 	void popup_centered(const Size2i &p_minsize = Size2i());
 	void popup_centered_clamped(const Size2i &p_size = Size2i(), float p_fallback_ratio = 0.75);
 
+	Rect2i fit_rect_in_parent(Rect2i p_rect, const Rect2i &p_parent_rect) const;
 	Size2 get_contents_minimum_size() const;
 	Size2 get_clamped_minimum_size() const;