Depsgraph: Fixes to make particle system behave more correct

Couple of main things here:

- Properly handle PSYS_UPDATE_* flags from DEG_id_tag_update.

  There are still some possible issues here related on the fact
  that we don't differentiate different PSYS_UPDATE_* flags here
  and handle the mall the same.

  Other possibility here is that object level particle settings
  evaluation might be forced when particle system evaluation is
  tagged for update. Didn't see actual issue here yet, but need
  a closer look.

- Don't tag non-object datablocks on visibility changes.

  Those don't depend on visibility anyway. This prevents particle
  settings IDs from flushing updates to all objects, causing all
  cached particles to be lsot.

- Only update translation and geometry components on visibility
  changes.

  Once again, this prevents particle cache from being invalidated.

  We might need to tag material components here still tho.

1 files changed, 60 insertions, 8 deletions

diff --git a/source/blender/depsgraph/intern/depsgraph_tag.cc b/source/blender/depsgraph/intern/depsgraph_tag.cc
index 07593cc55c8..7f3195c0778 100644
--- a/source/blender/depsgraph/intern/depsgraph_tag.cc
+++ b/source/blender/depsgraph/intern/depsgraph_tag.cc
@@ -153,6 +153,7 @@ void id_tag_update_object_data(Depsgraph *graph, IDDepsNode *id_node)
 				case OB_CURVE:
 				case OB_SURF:
 				case OB_FONT:
+				case OB_MBALL:
 					data_comp = id_node->find_component(DEG_NODE_TYPE_GEOMETRY);
 					break;
 				case OB_ARMATURE:
@@ -165,6 +166,8 @@ void id_tag_update_object_data(Depsgraph *graph, IDDepsNode *id_node)
 		case ID_ME:
 			data_comp = id_node->find_component(DEG_NODE_TYPE_GEOMETRY);
 			break;
+		case ID_PA:
+			return;
 	}
 	if (data_comp == NULL) {
 		DEG_ERROR_PRINTF("ERROR: Unable to find data component for %s\n",
@@ -190,6 +193,19 @@ void id_tag_update_object_time(Depsgraph *graph, IDDepsNode *id_node)
 	/* TODO(sergey): More components to tag here? */
 }
 
+void id_tag_update_particle(Depsgraph *graph, IDDepsNode *id_node)
+{
+	ComponentDepsNode *particle_comp =
+	        id_node->find_component(DEG_NODE_TYPE_PARAMETERS);
+	if (particle_comp == NULL) {
+		DEG_ERROR_PRINTF("ERROR: Unable to find particle component for %s\n",
+		                 id_node->id_orig->name);
+		BLI_assert(!"This is not supposed to happen!");
+		return;
+	}
+	particle_comp->tag_update(graph);
+}
+
 #ifdef WITH_COPY_ON_WRITE
 /* Tag corresponding to DEG_TAG_COPY_ON_WRITE. */
 void id_tag_update_copy_on_write(Depsgraph *graph, IDDepsNode *id_node)
@@ -226,12 +242,15 @@ void deg_graph_id_tag_update(Main *bmain, Depsgraph *graph, ID *id, int flag)
 	if (flag & OB_RECALC_TIME) {
 		id_tag_update_object_time(graph, id_node);
 	}
+	if (flag & PSYS_RECALC) {
+		/* TODO(sergey): Differentiate between different particle updates tags. */
+		id_tag_update_particle(graph, id_node);
+	}
 #ifdef WITH_COPY_ON_WRITE
 	if (flag & DEG_TAG_COPY_ON_WRITE) {
 		id_tag_update_copy_on_write(graph, id_node);
 	}
 #endif
-	// node->tag_update(deg_graph);
 }
 
 void deg_id_tag_update(Main *bmain, ID *id, int flag)
@@ -248,6 +267,44 @@ void deg_id_tag_update(Main *bmain, ID *id, int flag)
 	}
 }
 
+void deg_graph_on_visible_update(Main *bmain, Scene *scene, Depsgraph *graph)
+{
+	/* Nake sure objects are up to date. */
+	GHASH_FOREACH_BEGIN(DEG::IDDepsNode *, id_node, graph->id_hash)
+	{
+		const short idtype = GS(id_node->id_orig->name);
+		if (idtype != ID_OB) {
+			/* Ignore non-object nodes on visibility changes. */
+			continue;
+		}
+		int flag = 0;
+		/* We only tag components which needs an update. Tagging everything is
+		 * not a good idea because that might reset particles cache (or any
+		 * other type of cache).
+		 *
+		 * TODO(sergey): Need to generalize this somehow.
+		 */
+		if (idtype == ID_OB) {
+			Object *object = (Object *)id_node->id_orig;
+			flag |= OB_RECALC_OB;
+			if (ELEM(object->type, OB_MESH,
+			                       OB_CURVE,
+			                       OB_SURF,
+			                       OB_FONT,
+			                       OB_MBALL))
+			{
+				flag |= OB_RECALC_DATA;
+			}
+		}
+		deg_graph_id_tag_update(bmain, graph, id_node->id_orig, flag);
+	}
+	GHASH_FOREACH_END();
+	/* Make sure collection properties are up to date. */
+	IDDepsNode *scene_id_node = graph->find_id_node(&scene->id);
+	BLI_assert(scene_id_node != NULL);
+	scene_id_node->tag_update(graph);
+}
+
 }  /* namespace */
 
 }  // namespace DEG
@@ -301,13 +358,8 @@ void DEG_ids_flush_tagged(Main *bmain, Scene *scene)
 /* Update dependency graph when visible scenes/layers changes. */
 void DEG_graph_on_visible_update(Main *bmain, Scene *scene)
 {
-	(void) bmain;
-	DEG::Depsgraph *graph = reinterpret_cast<DEG::Depsgraph *>(scene->depsgraph_legacy);
-	GHASH_FOREACH_BEGIN(DEG::IDDepsNode *, id_node, graph->id_hash)
-	{
-		id_node->tag_update(graph);
-	}
-	GHASH_FOREACH_END();
+	DEG::Depsgraph *graph = (DEG::Depsgraph *)scene->depsgraph_legacy;
+	DEG::deg_graph_on_visible_update(bmain, scene, graph);
 }
 
 void DEG_on_visible_update(Main *bmain, const bool UNUSED(do_time))