Added multimesh physics interpolation for 2D transforms (MultiMeshInstance2D)

Replicated MultimeshInstance3D behaviour to MultiMeshInstance2D and added mesh_storage for 2D transform

Also call VisualInstance::_physics_interpolated_changed()

Use Node instead of VisualInstance. Addded comment

Fixed typo :)

Using CanvasItem instead of Node now. Made CanvasItem::_physics_interpolated_changed() protected

Author: Sch1nken

scene/2d/multimesh_instance_2d.cpp

@@ -42,8 +42,24 @@
 Callable MultiMeshInstance2D::_navmesh_source_geometry_parsing_callback;
 RID MultiMeshInstance2D::_navmesh_source_geometry_parser;
 
+void MultiMeshInstance2D::_refresh_interpolated() {
+	if (is_inside_tree() && multimesh.is_valid()) {
+		bool interpolated = is_physics_interpolated_and_enabled();
+		multimesh->set_physics_interpolated(interpolated);
+	}
+}
+
+void MultiMeshInstance2D::_physics_interpolated_changed() {
+	CanvasItem::_physics_interpolated_changed();
+	_refresh_interpolated();
+}
+
 void MultiMeshInstance2D::_notification(int p_what) {
 	switch (p_what) {
+		case NOTIFICATION_ENTER_TREE: {
+			_refresh_interpolated();
+			break;
+		}
 		case NOTIFICATION_DRAW: {
 			if (multimesh.is_valid()) {
 				draw_multimesh(multimesh, texture);
@@ -75,6 +91,7 @@ void MultiMeshInstance2D::set_multimesh(const Ref<MultiMesh> &p_multimesh) {
 	// Connect to the multimesh so the AABB can update when instance transforms are changed.
 	if (multimesh.is_valid()) {
 		multimesh->connect_changed(callable_mp((CanvasItem *)this, &CanvasItem::queue_redraw));
+		_refresh_interpolated();
 	}
 	queue_redraw();
 }

scene/2d/multimesh_instance_2d.h

@@ -43,7 +43,10 @@ class MultiMeshInstance2D : public Node2D {
 
 	Ref<Texture2D> texture;
 
+	void _refresh_interpolated();
+
 protected:
+	virtual void _physics_interpolated_changed() override;
 	void _notification(int p_what);
 	static void _bind_methods();
 

scene/main/canvas_item.h

@@ -140,8 +140,6 @@ class CanvasItem : public Node {
 
 	void _notify_transform(CanvasItem *p_node);
 
-	virtual void _physics_interpolated_changed() override;
-
 	static CanvasItem *current_item_drawn;
 	friend class Viewport;
 	void _refresh_texture_repeat_cache() const;
@@ -157,6 +155,8 @@ class CanvasItem : public Node {
 	bool _get(const StringName &p_name, Variant &r_ret) const;
 	void _get_property_list(List<PropertyInfo> *p_list) const;
 
+	virtual void _physics_interpolated_changed() override;
+
 	virtual void _update_self_texture_repeat(RS::CanvasItemTextureRepeat p_texture_repeat);
 	virtual void _update_self_texture_filter(RS::CanvasItemTextureFilter p_texture_filter);
 

servers/rendering/storage/mesh_storage.cpp

@@ -118,6 +118,37 @@ void RendererMeshStorage::multimesh_instance_set_transform(RID p_multimesh, int
 }
 
 void RendererMeshStorage::multimesh_instance_set_transform_2d(RID p_multimesh, int p_index, const Transform2D &p_transform) {
+	MultiMeshInterpolator *mmi = _multimesh_get_interpolator(p_multimesh);
+	if (mmi && mmi->interpolated) {
+		ERR_FAIL_COND(p_index >= mmi->_num_instances);
+		ERR_FAIL_COND(mmi->_vf_size_xform != 8);
+
+		int start = p_index * mmi->_stride;
+		float *ptr = mmi->_data_curr.ptrw();
+		ptr += start;
+
+		const Transform2D &t = p_transform;
+
+		ptr[0] = t.columns[0][0];
+		ptr[1] = t.columns[1][0];
+		ptr[2] = 0;
+		ptr[3] = t.columns[2][0];
+		ptr[4] = t.columns[0][1];
+		ptr[5] = t.columns[1][1];
+		ptr[6] = 0;
+		ptr[7] = t.columns[2][1];
+
+		_multimesh_add_to_interpolation_lists(p_multimesh, *mmi);
+
+#if defined(DEBUG_ENABLED) && defined(TOOLS_ENABLED)
+		if (!Engine::get_singleton()->is_in_physics_frame()) {
+			PHYSICS_INTERPOLATION_WARNING("MultiMesh interpolation is being triggered from outside physics process, this might lead to issues");
+		}
+#endif
+
+		return;
+	}
+
 	_multimesh_instance_set_transform_2d(p_multimesh, p_index, p_transform);
 }