Merge pull request #57179 from spacechase0/notify-world2d-changed-master

Propagate previously unused NOTIFICATION_WORLD_2D_CHANGED, make CanvasItem/CollisionObject2D use it

doc/classes/CanvasItem.xml

@@ -655,6 +655,9 @@
 		<constant name="NOTIFICATION_EXIT_CANVAS" value="33">
 			The [CanvasItem] has exited the canvas.
 		</constant>
+		<constant name="NOTIFICATION_WORLD_2D_CHANGED" value="36">
+			The [CanvasItem]'s active [World2D] changed.
+		</constant>
 		<constant name="TEXTURE_FILTER_PARENT_NODE" value="0" enum="TextureFilter">
 			The [CanvasItem] will inherit the filter from its parent.
 		</constant>

scene/2d/collision_object_2d.cpp

@@ -118,6 +118,15 @@ void CollisionObject2D::_notification(int p_what) {
 			}
 		} break;
 
+		case NOTIFICATION_WORLD_2D_CHANGED: {
+			RID space = get_world_2d()->get_space();
+			if (area) {
+				PhysicsServer2D::get_singleton()->area_set_space(rid, space);
+			} else {
+				PhysicsServer2D::get_singleton()->body_set_space(rid, space);
+			}
+		} break;
+
 		case NOTIFICATION_DISABLED: {
 			_apply_disabled();
 		} break;

scene/main/canvas_item.cpp

@@ -338,6 +338,10 @@ void CanvasItem::_notification(int p_what) {
 		case NOTIFICATION_VISIBILITY_CHANGED: {
 			emit_signal(SceneStringNames::get_singleton()->visibility_changed);
 		} break;
+		case NOTIFICATION_WORLD_2D_CHANGED: {
+			_exit_canvas();
+			_enter_canvas();
+		}
 	}
 }
 
@@ -1120,6 +1124,7 @@ void CanvasItem::_bind_methods() {
 	BIND_CONSTANT(NOTIFICATION_VISIBILITY_CHANGED);
 	BIND_CONSTANT(NOTIFICATION_ENTER_CANVAS);
 	BIND_CONSTANT(NOTIFICATION_EXIT_CANVAS);
+	BIND_CONSTANT(NOTIFICATION_WORLD_2D_CHANGED);
 
 	BIND_ENUM_CONSTANT(TEXTURE_FILTER_PARENT_NODE);
 	BIND_ENUM_CONSTANT(TEXTURE_FILTER_NEAREST);

scene/main/viewport.cpp

@@ -1091,7 +1091,11 @@ void Viewport::set_world_2d(const Ref<World2D> &p_world_2d) {
 	}
 
 	if (p_world_2d.is_valid()) {
+		bool do_propagate = world_2d.is_valid() && is_inside_tree();
 		world_2d = p_world_2d;
+		if (do_propagate) {
+			_propagate_world_2d_changed(this);
+		}
 	} else {
 		WARN_PRINT("Invalid world_2d");
 		world_2d = Ref<World2D>(memnew(World2D));
@@ -3839,6 +3843,25 @@ float Viewport::get_texture_mipmap_bias() const {
 
 #endif // _3D_DISABLED
 
+void Viewport::_propagate_world_2d_changed(Node *p_node) {
+	if (p_node != this) {
+		if (Object::cast_to<CanvasItem>(p_node)) {
+			p_node->notification(CanvasItem::NOTIFICATION_WORLD_2D_CHANGED);
+		} else {
+			Viewport *v = Object::cast_to<Viewport>(p_node);
+			if (v) {
+				if (v->world_2d.is_valid()) {
+					return;
+				}
+			}
+		}
+	}
+
+	for (int i = 0; i < p_node->get_child_count(); ++i) {
+		_propagate_world_2d_changed(p_node->get_child(i));
+	}
+}
+
 void Viewport::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_world_2d", "world_2d"), &Viewport::set_world_2d);
 	ClassDB::bind_method(D_METHOD("get_world_2d"), &Viewport::get_world_2d);

scene/main/viewport.h

@@ -734,6 +734,8 @@ public:
 	bool is_using_xr();
 #endif // _3D_DISABLED
 
+	void _propagate_world_2d_changed(Node *p_node);
+
 	void _validate_property(PropertyInfo &p_property) const;
 	Viewport();
 	~Viewport();