Groups and collection: initial integration

Since we are ditching layers from Blender (2.8) we need a replacement to
control groups visibility. This commit introduces collections as the building
blocks for groups, allowing users to control visibility as well as overrides
for groups.

Features
========

* Groups now have collections
    This way you can change the visibility of a collection inside a group, and add
    overrides which are part of the group and are prioritized over other overrides.

* Outliner
    Groups can inspect their collections, change visibility, and add/remove members.

    To change an override of a group collection, you need to select an instance of
    the group, and then you can choose "group" in the collection properties editor
    to edit this group active collection instead of the view layer one.

* Dupli groups overrides
    We can now have multiple instances of the same group with an original "override"
    and different overrides depending on the collection the instanced object is part
    of.

Technical
=========

* Layers
    We use the same api for groups and scene as much as possible.

Reviewers: sergey (depsgraph), mont29 (read/write and user count)
Differential Revision: https://developer.blender.org/D2892

1 files changed, 10 insertions, 126 deletions

diff --git a/source/blender/blenkernel/intern/scene.c b/source/blender/blenkernel/intern/scene.c
index ca31eed6552..b3d7e2affd3 100644
--- a/source/blender/blenkernel/intern/scene.c
+++ b/source/blender/blenkernel/intern/scene.c
@@ -151,89 +151,6 @@ static void remove_sequencer_fcurves(Scene *sce)
 	}
 }
 
-/* copy SceneCollection tree but keep pointing to the same objects */
-static void scene_collection_copy(SceneCollection *sc_dst, SceneCollection *sc_src, const int flag)
-{
-	BLI_duplicatelist(&sc_dst->objects, &sc_src->objects);
-	if ((flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
-		for (LinkData *link = sc_dst->objects.first; link; link = link->next) {
-			id_us_plus(link->data);
-		}
-	}
-
-	BLI_duplicatelist(&sc_dst->filter_objects, &sc_src->filter_objects);
-	if ((flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
-		for (LinkData *link = sc_dst->filter_objects.first; link; link = link->next) {
-			id_us_plus(link->data);
-		}
-	}
-
-	BLI_duplicatelist(&sc_dst->scene_collections, &sc_src->scene_collections);
-	for (SceneCollection *nsc_src = sc_src->scene_collections.first, *nsc_dst = sc_dst->scene_collections.first;
-	     nsc_src;
-	     nsc_src = nsc_src->next, nsc_dst = nsc_dst->next)
-	{
-		scene_collection_copy(nsc_dst, nsc_src, flag);
-	}
-}
-
-/* Find the equivalent SceneCollection in the new tree */
-static SceneCollection *scene_collection_from_new_tree(SceneCollection *sc_reference, SceneCollection *sc_dst, SceneCollection *sc_src)
-{
-	if (sc_src == sc_reference) {
-		return sc_dst;
-	}
-
-	for (SceneCollection *nsc_src = sc_src->scene_collections.first, *nsc_dst = sc_dst->scene_collections.first;
-	     nsc_src;
-	     nsc_src = nsc_src->next, nsc_dst = nsc_dst->next)
-	{
-		SceneCollection *found = scene_collection_from_new_tree(sc_reference, nsc_dst, nsc_src);
-		if (found != NULL) {
-			return found;
-		}
-	}
-	return NULL;
-}
-
-static void layer_collections_sync_flags(ListBase *layer_collections_dst, const ListBase *layer_collections_src)
-{
-	LayerCollection *layer_collection_dst = (LayerCollection *)layer_collections_dst->first;
-	const LayerCollection *layer_collection_src = (const LayerCollection *)layer_collections_src->first;
-	while (layer_collection_dst != NULL) {
-		layer_collection_dst->flag = layer_collection_src->flag;
-
-		if (layer_collection_dst->properties != NULL) {
-			IDP_FreeProperty(layer_collection_dst->properties);
-			MEM_SAFE_FREE(layer_collection_dst->properties);
-		}
-
-		if (layer_collection_src->properties != NULL) {
-			layer_collection_dst->properties = IDP_CopyProperty(layer_collection_src->properties);
-		}
-
-		layer_collections_sync_flags(&layer_collection_dst->layer_collections,
-		                             &layer_collection_src->layer_collections);
-
-		layer_collection_dst = layer_collection_dst->next;
-		layer_collection_src = layer_collection_src->next;
-	}
-}
-
-
-/* recreate the LayerCollection tree */
-static void layer_collections_recreate(
-        ViewLayer *view_layer_dst, ListBase *lb_src, SceneCollection *mc_dst, SceneCollection *mc_src)
-{
-	for (LayerCollection *lc_src = lb_src->first; lc_src; lc_src = lc_src->next) {
-		SceneCollection *sc_dst = scene_collection_from_new_tree(lc_src->scene_collection, mc_dst, mc_src);
-		BLI_assert(sc_dst);
-
-		/* instead of synchronizing both trees we simply re-create it */
-		BKE_collection_link(view_layer_dst, sc_dst);
-	}
-}
-
 /**
  * Only copy internal data of Scene ID from source to already allocated/initialized destination.
  * You probably nerver want to use that directly, use id_copy or BKE_id_copy_ex for typical needs.
@@ -254,11 +171,11 @@ void BKE_scene_copy_data(Main *bmain, Scene *sce_dst, const Scene *sce_src, cons
 
 	/* layers and collections */
 	sce_dst->collection = MEM_dupallocN(sce_src->collection);
-	SceneCollection *mc_src = BKE_collection_master(sce_src);
-	SceneCollection *mc_dst = BKE_collection_master(sce_dst);
+	SceneCollection *mc_src = BKE_collection_master(&sce_src->id);
+	SceneCollection *mc_dst = BKE_collection_master(&sce_dst->id);
 
-	/* recursively creates a new SceneCollection tree */
-	scene_collection_copy(mc_dst, mc_src, flag_subdata);
+	/* Recursively creates a new SceneCollection tree. */
+	BKE_collection_copy_data(mc_dst, mc_src, flag_subdata);
 
 	IDPropertyTemplate val = {0};
 	BLI_duplicatelist(&sce_dst->view_layers, &sce_src->view_layers);
@@ -266,39 +183,7 @@ void BKE_scene_copy_data(Main *bmain, Scene *sce_dst, const Scene *sce_src, cons
 	     view_layer_src;
 	     view_layer_src = view_layer_src->next, view_layer_dst = view_layer_dst->next)
 	{
-		if (view_layer_dst->id_properties != NULL) {
-			view_layer_dst->id_properties = IDP_CopyProperty_ex(view_layer_dst->id_properties, flag_subdata);
-		}
-		BKE_freestyle_config_copy(&view_layer_dst->freestyle_config, &view_layer_src->freestyle_config, flag_subdata);
-
-		view_layer_dst->stats = NULL;
-		view_layer_dst->properties_evaluated = NULL;
-		view_layer_dst->properties = IDP_New(IDP_GROUP, &val, ROOT_PROP);
-		IDP_MergeGroup_ex(view_layer_dst->properties, view_layer_src->properties, true, flag_subdata);
-
-		/* we start fresh with no overrides and no visibility flags set
-		 * instead of syncing both trees we simply unlink and relink the scene collection */
-		BLI_listbase_clear(&view_layer_dst->layer_collections);
-		BLI_listbase_clear(&view_layer_dst->object_bases);
-		BLI_listbase_clear(&view_layer_dst->drawdata);
-
-		layer_collections_recreate(view_layer_dst, &view_layer_src->layer_collections, mc_dst, mc_src);
-
-		/* Now we handle the syncing for visibility, selectability, ... */
-		layer_collections_sync_flags(&view_layer_dst->layer_collections, &view_layer_src->layer_collections);
-
-		Object *active_ob = OBACT(view_layer_src);
-		for (Base *base_src = view_layer_src->object_bases.first, *base_dst = view_layer_dst->object_bases.first;
-		     base_src;
-		     base_src = base_src->next, base_dst = base_dst->next)
-		{
-			base_dst->flag = base_src->flag;
-			base_dst->flag_legacy = base_src->flag_legacy;
-
-			if (base_dst->object == active_ob) {
-				view_layer_dst->basact = base_dst;
-			}
-		}
+		BKE_view_layer_copy_data(view_layer_dst, view_layer_src, mc_dst, mc_src, flag_subdata);
 	}
 
 	sce_dst->collection_properties = IDP_New(IDP_GROUP, &val, ROOT_PROP);
@@ -659,7 +544,7 @@ void BKE_scene_free_ex(Scene *sce, const bool do_id_user)
 	}
 
 	/* Master Collection */
-	BKE_collection_master_free(sce, do_id_user);
+	BKE_collection_master_free(&sce->id, do_id_user);
 	MEM_freeN(sce->collection);
 	sce->collection = NULL;
 
@@ -1092,7 +977,6 @@ void BKE_scene_set_background(Main *bmain, Scene *scene)
 {
 	Object *ob;
 	Group *group;
-	GroupObject *go;
 	
 	/* check for cyclic sets, for reading old files but also for definite security (py?) */
 	BKE_scene_validate_setscene(bmain, scene);
@@ -1107,11 +991,11 @@ void BKE_scene_set_background(Main *bmain, Scene *scene)
 
 	/* group flags again */
 	for (group = bmain->group.first; group; group = group->id.next) {
-		for (go = group->gobject.first; go; go = go->next) {
-			if (go->ob) {
-				go->ob->flag |= OB_FROMGROUP;
-			}
+		FOREACH_GROUP_OBJECT(group, object)
+		{
+			object->flag |= OB_FROMGROUP;
 		}
+		FOREACH_GROUP_OBJECT_END
 	}
 
 	/* copy layers and flags from bases to objects */