Depsgraph: Replace LIB_TAG_DOIT with hash lookup

This allows us to:

- Not mock around with tags stored in a global space,
    and not to iterate over all datablocks in the database
    to clear the tags.

- Properly deal with datablocks which might not be in main database.

    While it sounds crazy, it might be handy when dealing with preview,
    or some partial scene updates, such as motion paths.

- Avoids majority of places where depsgraph construction needed bmain.

    This is something what could help in blender2.8 branch.

From tests with production file here did not see any measurable slowdown.

Hopefully, there is no functional changes :)

1 files changed, 38 insertions, 81 deletions

diff --git a/source/blender/depsgraph/intern/builder/deg_builder_relations.cc b/source/blender/depsgraph/intern/builder/deg_builder_relations.cc
index bcb70792af1..c47006a7895 100644
--- a/source/blender/depsgraph/intern/builder/deg_builder_relations.cc
+++ b/source/blender/depsgraph/intern/builder/deg_builder_relations.cc
@@ -406,26 +406,11 @@ Depsgraph *DepsgraphRelationBuilder::getGraph()
 
 void DepsgraphRelationBuilder::begin_build()
 {
-	/* LIB_TAG_DOIT is used to indicate whether node for given ID was already
-	 * created or not.
-	 */
-	BKE_main_id_tag_all(bmain_, LIB_TAG_DOIT, false);
-	/* XXX nested node trees are notr included in tag-clearing above,
-	 * so we need to do this manually.
-	 */
-	FOREACH_NODETREE(bmain_, nodetree, id)
-	{
-		if (id != (ID *)nodetree) {
-			nodetree->id.tag &= ~LIB_TAG_DOIT;
-		}
-	}
-	FOREACH_NODETREE_END;
 }
 
 void DepsgraphRelationBuilder::build_group(Object *object, Group *group)
 {
-	ID *group_id = &group->id;
-	bool group_done = (group_id->tag & LIB_TAG_DOIT) != 0;
+	const bool group_done = built_map_.checkIsBuiltAndTag(group);
 	OperationKey object_local_transform_key(object != NULL ? &object->id : NULL,
 	                                        DEG_NODE_TYPE_TRANSFORM,
 	                                        DEG_OPCODE_TRANSFORM_LOCAL);
@@ -438,15 +423,13 @@ void DepsgraphRelationBuilder::build_group(Object *object, Group *group)
 			add_relation(dupli_transform_key, object_local_transform_key, "Dupligroup");
 		}
 	}
-	group_id->tag |= LIB_TAG_DOIT;
 }
 
 void DepsgraphRelationBuilder::build_object(Object *object)
 {
-	if (object->id.tag & LIB_TAG_DOIT) {
+	if (built_map_.checkIsBuiltAndTag(object)) {
 		return;
 	}
-	object->id.tag |= LIB_TAG_DOIT;
 	/* Object Transforms */
 	eDepsOperation_Code base_op = (object->parent) ? DEG_OPCODE_TRANSFORM_PARENT
 	                                               : DEG_OPCODE_TRANSFORM_LOCAL;
@@ -1233,24 +1216,18 @@ void DepsgraphRelationBuilder::build_driver_variables(ID *id, FCurve *fcu)
 
 void DepsgraphRelationBuilder::build_world(World *world)
 {
-	ID *world_id = &world->id;
-	if (world_id->tag & LIB_TAG_DOIT) {
+	if (built_map_.checkIsBuiltAndTag(world)) {
 		return;
 	}
-	world_id->tag |= LIB_TAG_DOIT;
-
-	build_animdata(world_id);
-
+	build_animdata(&world->id);
 	/* TODO: other settings? */
-
 	/* textures */
 	build_texture_stack(world->mtex);
-
 	/* world's nodetree */
 	if (world->nodetree != NULL) {
 		build_nodetree(world->nodetree);
 		ComponentKey ntree_key(&world->nodetree->id, DEG_NODE_TYPE_PARAMETERS);
-		ComponentKey world_key(world_id, DEG_NODE_TYPE_PARAMETERS);
+		ComponentKey world_key(&world->id, DEG_NODE_TYPE_PARAMETERS);
 		add_relation(ntree_key, world_key, "NTree->World Parameters");
 	}
 }
@@ -1609,10 +1586,9 @@ void DepsgraphRelationBuilder::build_obdata_geom(Object *object)
 		add_relation(geom_init_key, obdata_ubereval_key, "Object Geometry UberEval");
 	}
 
-	if (obdata->tag & LIB_TAG_DOIT) {
+	if (built_map_.checkIsBuiltAndTag(obdata)) {
 		return;
 	}
-	obdata->tag |= LIB_TAG_DOIT;
 
 	/* Link object data evaluation node to exit operation. */
 	OperationKey obdata_geom_eval_key(obdata, DEG_NODE_TYPE_GEOMETRY, DEG_OPCODE_PLACEHOLDER, "Geometry Eval");
@@ -1708,16 +1684,14 @@ void DepsgraphRelationBuilder::build_obdata_geom(Object *object)
 // TODO: Link scene-camera links in somehow...
 void DepsgraphRelationBuilder::build_camera(Object *object)
 {
-	Camera *cam = (Camera *)object->data;
-	ID *camera_id = &cam->id;
-	if (camera_id->tag & LIB_TAG_DOIT) {
+	Camera *camera = (Camera *)object->data;
+	if (built_map_.checkIsBuiltAndTag(camera)) {
 		return;
 	}
-	camera_id->tag |= LIB_TAG_DOIT;
 	/* DOF */
-	if (cam->dof_ob) {
+	if (camera->dof_ob) {
 		ComponentKey ob_param_key(&object->id, DEG_NODE_TYPE_PARAMETERS);
-		ComponentKey dof_ob_key(&cam->dof_ob->id, DEG_NODE_TYPE_TRANSFORM);
+		ComponentKey dof_ob_key(&camera->dof_ob->id, DEG_NODE_TYPE_TRANSFORM);
 		add_relation(dof_ob_key, ob_param_key, "Camera DOF");
 	}
 }
@@ -1725,36 +1699,33 @@ void DepsgraphRelationBuilder::build_camera(Object *object)
 /* Lamps */
 void DepsgraphRelationBuilder::build_lamp(Object *object)
 {
-	Lamp *la = (Lamp *)object->data;
-	ID *lamp_id = &la->id;
-	if (lamp_id->tag & LIB_TAG_DOIT) {
+	Lamp *lamp = (Lamp *)object->data;
+	if (built_map_.checkIsBuiltAndTag(lamp)) {
 		return;
 	}
-	lamp_id->tag |= LIB_TAG_DOIT;
 	/* lamp's nodetree */
-	if (la->nodetree != NULL) {
-		build_nodetree(la->nodetree);
-		ComponentKey parameters_key(lamp_id, DEG_NODE_TYPE_PARAMETERS);
-		ComponentKey nodetree_key(&la->nodetree->id, DEG_NODE_TYPE_PARAMETERS);
+	if (lamp->nodetree != NULL) {
+		build_nodetree(lamp->nodetree);
+		ComponentKey parameters_key(&lamp->id, DEG_NODE_TYPE_PARAMETERS);
+		ComponentKey nodetree_key(&lamp->nodetree->id, DEG_NODE_TYPE_PARAMETERS);
 		add_relation(nodetree_key, parameters_key, "NTree->Lamp Parameters");
 	}
 	/* textures */
-	build_texture_stack(la->mtex);
+	build_texture_stack(lamp->mtex);
 }
 
 void DepsgraphRelationBuilder::build_nodetree(bNodeTree *ntree)
 {
-	if (!ntree)
+	if (ntree == NULL) {
 		return;
-
-	ID *ntree_id = &ntree->id;
-
-	build_animdata(ntree_id);
-
-	OperationKey parameters_key(ntree_id,
+	}
+	if (built_map_.checkIsBuiltAndTag(ntree)) {
+		return;
+	}
+	build_animdata(&ntree->id);
+	OperationKey parameters_key(&ntree->id,
 	                            DEG_NODE_TYPE_PARAMETERS,
 	                            DEG_OPCODE_PARAMETERS_EVAL);
-
 	/* nodetree's nodes... */
 	LISTBASE_FOREACH (bNode *, bnode, &ntree->nodes) {
 		ID *id = bnode->id;
@@ -1784,10 +1755,7 @@ void DepsgraphRelationBuilder::build_nodetree(bNodeTree *ntree)
 		}
 		else if (bnode->type == NODE_GROUP) {
 			bNodeTree *group_ntree = (bNodeTree *)id;
-			if ((group_ntree->id.tag & LIB_TAG_DOIT) == 0) {
-				build_nodetree(group_ntree);
-				group_ntree->id.tag |= LIB_TAG_DOIT;
-			}
+			build_nodetree(group_ntree);
 			OperationKey group_parameters_key(&group_ntree->id,
 			                                  DEG_NODE_TYPE_PARAMETERS,
 			                                  DEG_OPCODE_PARAMETERS_EVAL);
@@ -1800,27 +1768,22 @@ void DepsgraphRelationBuilder::build_nodetree(bNodeTree *ntree)
 }
 
 /* Recursively build graph for material */
-void DepsgraphRelationBuilder::build_material(Material *ma)
+void DepsgraphRelationBuilder::build_material(Material *material)
 {
-	ID *ma_id = &ma->id;
-	if (ma_id->tag & LIB_TAG_DOIT) {
+	if (built_map_.checkIsBuiltAndTag(material)) {
 		return;
 	}
-	ma_id->tag |= LIB_TAG_DOIT;
-
 	/* animation */
-	build_animdata(ma_id);
-
+	build_animdata(&material->id);
 	/* textures */
-	build_texture_stack(ma->mtex);
-
+	build_texture_stack(material->mtex);
 	/* material's nodetree */
-	if (ma->nodetree != NULL) {
-		build_nodetree(ma->nodetree);
-		OperationKey ntree_key(&ma->nodetree->id,
+	if (material->nodetree != NULL) {
+		build_nodetree(material->nodetree);
+		OperationKey ntree_key(&material->nodetree->id,
 		                       DEG_NODE_TYPE_PARAMETERS,
 		                       DEG_OPCODE_PARAMETERS_EVAL);
-		OperationKey material_key(&ma->id,
+		OperationKey material_key(&material->id,
 		                          DEG_NODE_TYPE_SHADING,
 		                          DEG_OPCODE_PLACEHOLDER,
 		                          "Material Update");
@@ -1829,28 +1792,22 @@ void DepsgraphRelationBuilder::build_material(Material *ma)
 }
 
 /* Recursively build graph for texture */
-void DepsgraphRelationBuilder::build_texture(Tex *tex)
+void DepsgraphRelationBuilder::build_texture(Tex *texture)
 {
-	ID *tex_id = &tex->id;
-	if (tex_id->tag & LIB_TAG_DOIT) {
+	if (built_map_.checkIsBuiltAndTag(texture)) {
 		return;
 	}
-	tex_id->tag |= LIB_TAG_DOIT;
-
 	/* texture itself */
-	build_animdata(tex_id);
-
+	build_animdata(&texture->id);
 	/* texture's nodetree */
-	build_nodetree(tex->nodetree);
+	build_nodetree(texture->nodetree);
 }
 
 /* Texture-stack attached to some shading datablock */
 void DepsgraphRelationBuilder::build_texture_stack(MTex **texture_stack)
 {
-	int i;
-
 	/* for now assume that all texture-stacks have same number of max items */
-	for (i = 0; i < MAX_MTEX; i++) {
+	for (int i = 0; i < MAX_MTEX; i++) {
 		MTex *mtex = texture_stack[i];
 		if (mtex && mtex->tex)
 			build_texture(mtex->tex);