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, 19 insertions, 17 deletions

diff --git a/source/blender/editors/object/object_relations.c b/source/blender/editors/object/object_relations.c
index fb1c7f04a95..8848b69a927 100644
--- a/source/blender/editors/object/object_relations.c
+++ b/source/blender/editors/object/object_relations.c
@@ -342,17 +342,15 @@ static int make_proxy_exec(bContext *C, wmOperator *op)
 {
 	Main *bmain = CTX_data_main(C);
 	Object *ob, *gob = ED_object_active_context(C);
-	GroupObject *go;
 	Scene *scene = CTX_data_scene(C);
 	ViewLayer *view_layer = CTX_data_view_layer(C);
 
 	if (gob->dup_group != NULL) {
-		go = BLI_findlink(&gob->dup_group->gobject, RNA_enum_get(op->ptr, "object"));
-		ob = go->ob;
+		Base *base = BLI_findlink(&gob->dup_group->view_layer->object_bases, RNA_enum_get(op->ptr, "object"));
+		ob = base->object;
 	}
 	else {
 		ob = gob;
-		gob = NULL;
 	}
 
 	if (ob) {
@@ -397,17 +395,18 @@ static const EnumPropertyItem *proxy_group_object_itemf(bContext *C, PointerRNA
 	int totitem = 0;
 	int i = 0;
 	Object *ob = ED_object_active_context(C);
-	GroupObject *go;
 
 	if (!ob || !ob->dup_group)
 		return DummyRNA_DEFAULT_items;
 
 	/* find the object to affect */
-	for (go = ob->dup_group->gobject.first; go; go = go->next) {
-		item_tmp.identifier = item_tmp.name = go->ob->id.name + 2;
+	FOREACH_GROUP_OBJECT(ob->dup_group, object)
+	{
+		item_tmp.identifier = item_tmp.name = object->id.name + 2;
 		item_tmp.value = i++;
 		RNA_enum_item_add(&item, &totitem, &item_tmp);
 	}
+	FOREACH_GROUP_OBJECT_END
 
 	RNA_enum_item_end(&item, &totitem);
 	*r_free = true;
@@ -1368,10 +1367,10 @@ static int make_links_scene_exec(bContext *C, wmOperator *op)
 		return OPERATOR_CANCELLED;
 	}
 
-	SceneCollection *sc_to = BKE_collection_master(scene_to);
+	SceneCollection *sc_to = BKE_collection_master(&scene_to->id);
 	CTX_DATA_BEGIN (C, Base *, base, selected_bases)
 	{
-		BKE_collection_object_add(scene_to, sc_to, base->object);
+		BKE_collection_object_add(&scene_to->id, sc_to, base->object);
 	}
 	CTX_DATA_END;
 
@@ -1691,12 +1690,11 @@ static void single_object_users_scene_collection(Main *bmain, Scene *scene, Scen
 static void single_object_users(Main *bmain, Scene *scene, View3D *v3d, const int flag, const bool copy_groups)
 {
 	Group *group, *groupn;
-	GroupObject *go;
 
 	clear_sca_new_poins();  /* BGE logic */
 
 	/* duplicate all the objects of the scene */
-	SceneCollection *msc = BKE_collection_master(scene);
+	SceneCollection *msc = BKE_collection_master(&scene->id);
 	single_object_users_scene_collection(bmain, scene, msc, flag, copy_groups);
 
 	/* loop over ViewLayers and assign the pointers accordingly */
@@ -1708,22 +1706,26 @@ static void single_object_users(Main *bmain, Scene *scene, View3D *v3d, const in
 
 	/* duplicate groups that consist entirely of duplicated objects */
 	for (group = bmain->group.first; group; group = group->id.next) {
-		if (copy_groups && group->gobject.first) {
+		if (copy_groups && group->view_layer->object_bases.first) {
 			bool all_duplicated = true;
 
-			for (go = group->gobject.first; go; go = go->next) {
-				if (!(go->ob && (go->ob->id.newid))) {
+			FOREACH_GROUP_OBJECT(group, object)
+			{
+				if (object->id.newid == NULL) {
 					all_duplicated = false;
 					break;
 				}
 			}
+			FOREACH_GROUP_OBJECT_END
 
 			if (all_duplicated) {
 				groupn = ID_NEW_SET(group, BKE_group_copy(bmain, group));
 
-				for (go = groupn->gobject.first; go; go = go->next) {
-					go->ob = (Object *)go->ob->id.newid;
+				FOREACH_GROUP_BASE(groupn, base)
+				{
+					base->object = (Object *)base->object->id.newid;
 				}
+				FOREACH_GROUP_BASE_END
 			}
 		}
 	}
@@ -2151,7 +2153,7 @@ static bool make_local_all__instance_indirect_unused(Main *bmain, Scene *scene,
 
 			id_us_plus(&ob->id);
 
-			BKE_collection_object_add(scene, sc, ob);
+			BKE_collection_object_add(&scene->id, sc, ob);
 			base = BKE_view_layer_base_find(view_layer, ob);
 			base->flag |= BASE_SELECTED;
 			BKE_scene_object_base_flag_sync_from_base(base);