Ported: Fix 2D MultiMesh hierarchical culling

Fixes updating local bounds for MultiMeshes used in canvas items by introducing a back link.
- lawnjelly
ad577e3c7e

drivers/dummy/rasterizer_dummy.h

@@ -448,6 +448,7 @@ public:
 	AABB _multimesh_get_aabb(RID p_multimesh) const { return AABB(); }
 
 	MMInterpolator *_multimesh_get_interpolator(RID p_multimesh) const { return nullptr; }
+	void multimesh_attach_canvas_item(RID p_multimesh, RID p_canvas_item, bool p_attach) {}
 
 	/* IMMEDIATE API */
 

drivers/gles2/rasterizer_storage_gles2.cpp

@@ -3388,6 +3388,24 @@ RasterizerStorage::MMInterpolator *RasterizerStorageGLES2::_multimesh_get_interp
 	return &multimesh->interpolator;
 }
 
+void RasterizerStorageGLES2::multimesh_attach_canvas_item(RID p_multimesh, RID p_canvas_item, bool p_attach) {
+	MultiMesh *multimesh = multimesh_owner.getornull(p_multimesh);
+	ERR_FAIL_NULL(multimesh);
+	ERR_FAIL_COND(!p_canvas_item.is_valid());
+
+	if (p_attach) {
+		int64_t found = multimesh->linked_canvas_items.find(p_canvas_item);
+		if (found == -1) {
+			multimesh->linked_canvas_items.push_back(p_canvas_item);
+		}
+	} else {
+		int64_t found = multimesh->linked_canvas_items.find(p_canvas_item);
+		if (found != -1) {
+			multimesh->linked_canvas_items.remove_unordered(found);
+		}
+	}
+}
+
 void RasterizerStorageGLES2::update_dirty_multimeshes() {
 	while (multimesh_update_list.first()) {
 		MultiMesh *multimesh = multimesh_update_list.first()->self();
@@ -3457,6 +3475,14 @@ void RasterizerStorageGLES2::update_dirty_multimeshes() {
 			}
 
 			multimesh->aabb = aabb;
+
+			// Inform any linked canvas items that bounds have changed
+			// (for hierarchical culling).
+			int num_linked = multimesh->linked_canvas_items.size();
+			for (int n = 0; n < num_linked; n++) {
+				const RID &rid = multimesh->linked_canvas_items[n];
+				RSG::canvas->_canvas_item_invalidate_local_bound(rid);
+			}
 		}
 
 		multimesh->dirty_aabb = false;
@@ -4129,7 +4155,7 @@ void RasterizerStorageGLES2::update_dirty_skeletons() {
 		int num_linked = skeleton->linked_canvas_items.size();
 		for (int n = 0; n < num_linked; n++) {
 			const RID &rid = skeleton->linked_canvas_items[n];
-			RSG::canvas->_canvas_item_skeleton_moved(rid);
+			RSG::canvas->_canvas_item_invalidate_local_bound(rid);
 		}
 
 		ele = ele->next();
@@ -5700,6 +5726,14 @@ bool RasterizerStorageGLES2::free(RID p_rid) {
 		_interpolation_data.notify_free_multimesh(p_rid);
 
 		MultiMesh *multimesh = multimesh_owner.get(p_rid);
+
+		// remove any references in linked canvas items
+		int num_linked = multimesh->linked_canvas_items.size();
+		for (int n = 0; n < num_linked; n++) {
+			const RID &rid = multimesh->linked_canvas_items[n];
+			RSG::canvas->_canvas_item_remove_references(rid, p_rid);
+		}
+
 		multimesh->instance_remove_deps();
 
 		if (multimesh->mesh.is_valid()) {

drivers/gles2/rasterizer_storage_gles2.h

@@ -787,6 +787,7 @@ public:
 		bool dirty_data;
 
 		MMInterpolator interpolator;
+		LocalVector<RID> linked_canvas_items;
 
 		MultiMesh() :
 				size(0),
@@ -833,6 +834,7 @@ public:
 
 	virtual AABB _multimesh_get_aabb(RID p_multimesh) const;
 	virtual MMInterpolator *_multimesh_get_interpolator(RID p_multimesh) const;
+	virtual void multimesh_attach_canvas_item(RID p_multimesh, RID p_canvas_item, bool p_attach);
 
 	void update_dirty_multimeshes();
 

servers/rendering/rasterizer.h

@@ -376,6 +376,7 @@ public:
 	virtual void multimesh_set_visible_instances(RID p_multimesh, int p_visible);
 	virtual int multimesh_get_visible_instances(RID p_multimesh) const;
 	virtual AABB multimesh_get_aabb(RID p_multimesh) const;
+	virtual void multimesh_attach_canvas_item(RID p_multimesh, RID p_canvas_item, bool p_attach) = 0;
 
 	virtual RID _multimesh_create() = 0;
 	virtual void _multimesh_allocate(RID p_multimesh, int p_instances, RS::MultimeshTransformFormat p_transform_format, RS::MultimeshColorFormat p_color_format, RS::MultimeshCustomDataFormat p_data = RS::MULTIMESH_CUSTOM_DATA_NONE) = 0;
@@ -681,6 +682,8 @@ public:
 				TYPE_MULTIRECT,
 			};
 
+			virtual bool contains_reference(const RID &p_rid) const { return false; }
+
 			Type type;
 			virtual ~Command() {}
 		};
@@ -813,7 +816,17 @@ public:
 			RID multimesh;
 			RID texture;
 			RID normal_map;
+			RID canvas_item;
+			virtual bool contains_reference(const RID &p_rid) const { return multimesh == p_rid; }
+
 			CommandMultiMesh() { type = TYPE_MULTIMESH; }
+
+			virtual ~CommandMultiMesh() {
+				// Remove any backlinks from multimesh to canvas item.
+				if (multimesh.is_valid()) {
+					RasterizerStorage::base_singleton->multimesh_attach_canvas_item(multimesh, canvas_item, false);
+				}
+			}
 		};
 
 		struct CommandCircle : public Command {
@@ -1052,6 +1065,20 @@ public:
 			return rect;
 		}
 
+		void remove_references(const RID &p_rid) {
+			for (int i = commands.size() - 1; i >= 0; i--) {
+				if (commands[i]->contains_reference(p_rid)) {
+					memdelete(commands[i]);
+
+					// This could possibly be unordered if occurring close
+					// to canvas_item deletion, but is
+					// unlikely to make much performance difference,
+					// and is safer.
+					commands.remove(i);
+				}
+			}
+		}
+
 		void clear() {
 			for (int i = 0; i < commands.size(); i++) {
 				memdelete(commands[i]);

servers/rendering/rendering_server_canvas.cpp

@@ -1417,10 +1417,17 @@ void RenderingServerCanvas::canvas_item_add_multimesh(RID p_item, RID p_mesh, RI
 	mm->multimesh = p_mesh;
 	mm->texture = p_texture;
 	mm->normal_map = p_normal_map;
+	mm->canvas_item = p_item;
 
 	canvas_item->rect_dirty = true;
 	canvas_item->commands.push_back(mm);
 	_make_bound_dirty(canvas_item);
+
+	// Attach to multimesh a backlink to enable updating
+	// the canvas item local bound when the multimesh changes.
+	if (p_mesh.is_valid()) {
+		RSG::storage->multimesh_attach_canvas_item(p_mesh, p_item, true);
+	}
 }
 
 void RenderingServerCanvas::canvas_item_add_clip_ignore(RID p_item, bool p_ignore) {
@@ -1584,7 +1591,16 @@ void RenderingServerCanvas::canvas_item_attach_skeleton(RID p_item, RID p_skelet
 	}
 }
 
-void RenderingServerCanvas::_canvas_item_skeleton_moved(RID p_item) {
+// Canvas items may contain references to other resources (such as MultiMesh).
+// If the resources are deleted first, and the canvas_item retains references, it
+// will crash / error when it tries to access these.
+void RenderingServerCanvas::_canvas_item_remove_references(RID p_item, RID p_rid) {
+	Item *canvas_item = canvas_item_owner.getornull(p_item);
+	ERR_FAIL_COND(!canvas_item);
+	canvas_item->remove_references(p_rid);
+}
+
+void RenderingServerCanvas::_canvas_item_invalidate_local_bound(RID p_item) {
 	Item *canvas_item = canvas_item_owner.getornull(p_item);
 	ERR_FAIL_COND(!canvas_item);
 	_make_bound_dirty(canvas_item);

servers/rendering/rendering_server_canvas.h

@@ -256,7 +256,6 @@ public:
 	void canvas_item_set_use_parent_material(RID p_item, bool p_enable);
 
 	void canvas_item_attach_skeleton(RID p_item, RID p_skeleton);
-	void _canvas_item_skeleton_moved(RID p_item);
 	void canvas_item_set_skeleton_relative_xform(RID p_item, Transform2D p_relative_xform);
 	Rect2 _debug_canvas_item_get_rect(RID p_item);
 	Rect2 _debug_canvas_item_get_local_bound(RID p_item);
@@ -265,6 +264,9 @@ public:
 	void canvas_item_reset_physics_interpolation(RID p_item);
 	void canvas_item_transform_physics_interpolation(RID p_item, Transform2D p_transform);
 
+	void _canvas_item_invalidate_local_bound(RID p_item);
+	void _canvas_item_remove_references(RID p_item, RID p_rid);
+
 	RID canvas_light_create();
 	void canvas_light_attach_to_canvas(RID p_light, RID p_canvas);
 	void canvas_light_set_enabled(RID p_light, bool p_enabled);