Collections and groups unification

OVERVIEW

* In 2.7 terminology, all layers and groups are now collection datablocks.
* These collections are nestable, linkable, instanceable, overrideable, ..
  which opens up new ways to set up scenes and link + override data.
* Viewport/render visibility and selectability are now a part of the collection
  and shared across all view layers and linkable.
* View layers define which subset of the scene collection hierarchy is excluded
  for each. For many workflows one view layer can be used, these are more of an
  advanced feature now.

OUTLINER

* The outliner now has a "View Layer" display mode instead of "Collections",
  which can display the collections and/or objects in the view layer.
* In this display mode, collections can be excluded with the right click menu.
  These will then be greyed out and their objects will be excluded.
* To view collections not linked to any scene, the "Blender File" display mode
  can be used, with the new filtering option to just see Colleciton datablocks.
* The outliner right click menus for collections and objects were reorganized.
* Drag and drop still needs to be improved. Like before, dragging the icon or
  text gives different results, we'll unify this later.

LINKING AND OVERRIDES

* Collections can now be linked into the scene without creating an instance,
  with the link/append operator or from the collections view in the outliner.
* Collections can get static overrides with the right click menu in the outliner,
  but this is rather unreliable and not clearly communicated at the moment.
* We still need to improve the make override operator to turn collection instances
  into collections with overrides directly in the scene.

PERFORMANCE

* We tried to make performance not worse than before and improve it in some
  cases. The main thing that's still a bit slower is multiple scenes, we have to
  change the layer syncing to only updated affected scenes.
* Collections keep a list of their parent collections for faster incremental
  updates in syncing and caching.
* View layer bases are now in a object -> base hash to avoid quadratic time
  lookups internally and in API functions like visible_get().

VERSIONING

* Compatibility with 2.7 files should be improved due to the new visibility
  controls. Of course users may not want to set up their scenes differently
  now to avoid having separate layers and groups.
* Compatibility with 2.8 is mostly there, and was tested on Eevee demo and Hero
  files. There's a few things which are know to be not quite compatible, like
  nested layer collections inside groups.
* The versioning code for 2.8 files is quite complicated, and isolated behind
  #ifdef so it can be removed at the end of the release cycle.

KNOWN ISSUES

* The G-key group operators in the 3D viewport were left mostly as is, they
  need to be modified still to fit better.
* Same for the groups panel in the object properties. This needs to be updated
  still, or perhaps replaced by something better.
* Collections must all have a unique name. Less restrictive namespacing is to
  be done later, we'll have to see how important this is as all objects within
  the collections must also have a unique name anyway.
* Full scene copy and delete scene are exactly doing the right thing yet.

Differential Revision: https://developer.blender.org/D3383

https://code.blender.org/2018/05/collections-and-groups/

1 files changed, 71 insertions, 36 deletions

diff --git a/source/blender/editors/object/object_edit.c b/source/blender/editors/object/object_edit.c
index b9a7da02611..a2e91761a38 100644
--- a/source/blender/editors/object/object_edit.c
+++ b/source/blender/editors/object/object_edit.c
@@ -1506,11 +1506,12 @@ bool ED_object_editmode_calc_active_center(Object *obedit, const bool select_onl
 
 static int move_to_collection_exec(bContext *C, wmOperator *op)
 {
+	Main *bmain = CTX_data_main(C);
 	Scene *scene = CTX_data_scene(C);
 	PropertyRNA *prop = RNA_struct_find_property(op->ptr, "collection_index");
-	const bool is_add = RNA_boolean_get(op->ptr, "is_add");
+	const bool is_link = STREQ(op->idname, "OBJECT_OT_link_to_collection");
 	const bool is_new = RNA_boolean_get(op->ptr, "is_new");
-	SceneCollection *scene_collection;
+	Collection *collection;
 
 	if (!RNA_property_is_set(op->ptr, prop)) {
 		BKE_report(op->reports, RPT_ERROR, "No collection selected");
@@ -1518,8 +1519,8 @@ static int move_to_collection_exec(bContext *C, wmOperator *op)
 	}
 
 	int collection_index = RNA_property_int_get(op->ptr, prop);
-	scene_collection = BKE_collection_from_index(CTX_data_scene(C), collection_index);
-	if (scene_collection == NULL) {
+	collection = BKE_collection_from_index(CTX_data_scene(C), collection_index);
+	if (collection == NULL) {
 		BKE_report(op->reports, RPT_ERROR, "Unexpected error, collection not found");
 		return OPERATOR_CANCELLED;
 	}
@@ -1540,24 +1541,24 @@ static int move_to_collection_exec(bContext *C, wmOperator *op)
 	if (is_new) {
 		char new_collection_name[MAX_NAME];
 		RNA_string_get(op->ptr, "new_collection_name", new_collection_name);
-		scene_collection = BKE_collection_add(&scene->id, scene_collection, COLLECTION_TYPE_NONE, new_collection_name);
+		collection = BKE_collection_add(bmain, collection, new_collection_name);
 	}
 
 	if ((single_object != NULL) &&
-	    is_add &&
-	    BLI_findptr(&scene_collection->objects, single_object, offsetof(LinkData, data)))
+	    is_link &&
+	    BLI_findptr(&collection->gobject, single_object, offsetof(CollectionObject, ob)))
 	{
-		BKE_reportf(op->reports, RPT_ERROR, "%s already in %s", single_object->id.name + 2, scene_collection->name);
+		BKE_reportf(op->reports, RPT_ERROR, "%s already in %s", single_object->id.name + 2, collection->id.name + 2);
 		return OPERATOR_CANCELLED;
 	}
 
 	CTX_DATA_BEGIN (C, Object *, ob, selected_objects)
 	{
-		if (!is_add) {
-			BKE_collection_object_move(&scene->id, scene_collection, NULL, ob);
+		if (!is_link) {
+			BKE_collection_object_move(bmain, scene, collection, NULL, ob);
 		}
 		else {
-			BKE_collection_object_add(&scene->id, scene_collection, ob);
+			BKE_collection_object_add(bmain, collection, ob);
 		}
 	}
 	CTX_DATA_END;
@@ -1566,8 +1567,8 @@ static int move_to_collection_exec(bContext *C, wmOperator *op)
 	            RPT_INFO,
 	            "%s %s to %s",
 	            (single_object != NULL) ? single_object->id.name + 2 : "Objects",
-	            is_add ? "added" : "moved",
-	            scene_collection->name);
+	            is_link ? "linked" : "moved",
+	            collection->id.name + 2);
 
 	DEG_relations_tag_update(CTX_data_main(C));
 	DEG_id_tag_update(&scene->id, 0);
@@ -1579,26 +1580,27 @@ static int move_to_collection_exec(bContext *C, wmOperator *op)
 	return OPERATOR_FINISHED;
 }
 
-typedef struct MoveToCollectionData {
+struct MoveToCollectionData {
 	struct MoveToCollectionData *next, *prev;
 	int index;
-	struct SceneCollection *collection;
+	struct Collection *collection;
 	struct ListBase submenus;
 	PointerRNA ptr;
 	struct wmOperatorType *ot;
-} MoveToCollectionData;
+};
 
 static int move_to_collection_menus_create(wmOperator *op, MoveToCollectionData *menu)
 {
 	int index = menu->index;
-	for (SceneCollection *scene_collection = menu->collection->scene_collections.first;
-	     scene_collection != NULL;
-	     scene_collection = scene_collection->next)
+	for (CollectionChild *child = menu->collection->children.first;
+	     child != NULL;
+	     child = child->next)
 	{
+		Collection *collection = child->collection;
 		MoveToCollectionData *submenu = MEM_callocN(sizeof(MoveToCollectionData),
 		                                            "MoveToCollectionData submenu - expected memleak");
 		BLI_addtail(&menu->submenus, submenu);
-		submenu->collection = scene_collection;
+		submenu->collection = collection;
 		submenu->index = ++index;
 		index = move_to_collection_menus_create(op, submenu);
 		submenu->ot = op->type;
@@ -1631,11 +1633,19 @@ static void move_to_collection_menus_free(MoveToCollectionData **menu)
 static void move_to_collection_menu_create(bContext *UNUSED(C), uiLayout *layout, void *menu_v)
 {
 	MoveToCollectionData *menu = menu_v;
+	const char *name;
+
+	if (menu->collection->flag & COLLECTION_IS_MASTER) {
+		name = IFACE_("Scene Collection");
+	}
+	else {
+		name = menu->collection->id.name + 2;
+	}
 
 	uiItemIntO(layout,
-	           menu->collection->name,
+	           name,
 	           ICON_NONE,
-	           "OBJECT_OT_move_to_collection",
+		       menu->ot->idname,
 	           "collection_index",
 	           menu->index);
 	uiItemS(layout);
@@ -1658,7 +1668,6 @@ static void move_to_collection_menu_create(bContext *UNUSED(C), uiLayout *layout
 	                "New Collection",
 	                ICON_ZOOMIN,
 	                menu->ptr.data,
-	                /* We use invoke here so we can read ctrl from event. */
 	                WM_OP_INVOKE_DEFAULT,
 	                0,
 	                NULL);
@@ -1668,15 +1677,15 @@ static void move_to_collection_menus_items(uiLayout *layout, MoveToCollectionDat
 {
 	if (BLI_listbase_is_empty(&menu->submenus)) {
 		uiItemIntO(layout,
-		           menu->collection->name,
+		           menu->collection->id.name + 2,
 		           ICON_NONE,
-		           "OBJECT_OT_move_to_collection",
+		           menu->ot->idname,
 		           "collection_index",
 		           menu->index);
 	}
 	else {
 		uiItemMenuF(layout,
-		            menu->collection->name,
+		            menu->collection->id.name + 2,
 		            ICON_NONE,
 		            move_to_collection_menu_create,
 		            menu);
@@ -1686,8 +1695,10 @@ static void move_to_collection_menus_items(uiLayout *layout, MoveToCollectionDat
 /* This is allocated statically because we need this available for the menus creation callback. */
 static MoveToCollectionData *master_collection_menu = NULL;
 
-static int move_to_collection_invoke(bContext *C, wmOperator *op, const wmEvent *event)
+static int move_to_collection_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
 {
+	Scene *scene = CTX_data_scene(C);
+
 	/* Reset the menus data for the current master collection, and free previously allocated data. */
 	move_to_collection_menus_free(&master_collection_menu);
 
@@ -1695,16 +1706,15 @@ static int move_to_collection_invoke(bContext *C, wmOperator *op, const wmEvent
 	prop = RNA_struct_find_property(op->ptr, "collection_index");
 	if (RNA_property_is_set(op->ptr, prop)) {
 		int collection_index = RNA_property_int_get(op->ptr, prop);
-		RNA_boolean_set(op->ptr, "is_add", event->ctrl);
 
 		if (RNA_boolean_get(op->ptr, "is_new")) {
 			prop = RNA_struct_find_property(op->ptr, "new_collection_name");
 			if (!RNA_property_is_set(op->ptr, prop)) {
 				char name[MAX_NAME];
-				SceneCollection *scene_collection;
+				Collection *collection;
 
-				scene_collection = BKE_collection_from_index(CTX_data_scene(C), collection_index);
-				BKE_collection_new_name_get(&CTX_data_scene(C)->id, scene_collection, name);
+				collection = BKE_collection_from_index(scene, collection_index);
+				BKE_collection_new_name_get(collection, name);
 
 				RNA_property_string_set(op->ptr, prop, name);
 				return WM_operator_props_dialog_popup(C, op, 10 * UI_UNIT_X, 5 * UI_UNIT_Y);
@@ -1713,7 +1723,7 @@ static int move_to_collection_invoke(bContext *C, wmOperator *op, const wmEvent
 		return move_to_collection_exec(C, op);
 	}
 
-	SceneCollection *master_collection = BKE_collection_master(&CTX_data_scene(C)->id);
+	Collection *master_collection = BKE_collection_master(scene);
 
 	/* We need the data to be allocated so it's available during menu drawing.
 	 * Technically we could use wmOperator->customdata. However there is no free callback
@@ -1733,10 +1743,10 @@ static int move_to_collection_invoke(bContext *C, wmOperator *op, const wmEvent
 	uiLayout *layout;
 
 	/* Build the menus. */
-	pup = UI_popup_menu_begin(C, IFACE_("Move to Collection"), ICON_NONE);
+	const char *title = CTX_IFACE_(op->type->translation_context, op->type->name);
+	pup = UI_popup_menu_begin(C, title, ICON_NONE);
 	layout = UI_popup_menu_layout(pup);
 
-	/* We use invoke here so we can read ctrl from event. */
 	uiLayoutSetOperatorContext(layout, WM_OP_INVOKE_DEFAULT);
 
 	move_to_collection_menu_create(C, layout, master_collection_menu);
@@ -1752,7 +1762,7 @@ void OBJECT_OT_move_to_collection(wmOperatorType *ot)
 
 	/* identifiers */
 	ot->name = "Move to Collection";
-	ot->description = "Move to a collection only (Ctrl to add)";
+	ot->description = "Move objects to a scene collection";
 	ot->idname = "OBJECT_OT_move_to_collection";
 
 	/* api callbacks */
@@ -1766,7 +1776,32 @@ void OBJECT_OT_move_to_collection(wmOperatorType *ot)
 	prop = RNA_def_int(ot->srna, "collection_index", COLLECTION_INVALID_INDEX, COLLECTION_INVALID_INDEX, INT_MAX,
 	                   "Collection Index", "Index of the collection to move to", 0, INT_MAX);
 	RNA_def_property_flag(prop, PROP_SKIP_SAVE | PROP_HIDDEN);
-	prop = RNA_def_boolean(ot->srna, "is_add", false, "Add", "Keep object in original collections as well");
+	prop = RNA_def_boolean(ot->srna, "is_new", false, "New", "Move objects to a new collection");
+	RNA_def_property_flag(prop, PROP_SKIP_SAVE | PROP_HIDDEN);
+	prop = RNA_def_string(ot->srna, "new_collection_name", NULL, MAX_NAME, "Name",
+	                      "Name of the newly added collection");
+	RNA_def_property_flag(prop, PROP_SKIP_SAVE);
+}
+
+void OBJECT_OT_link_to_collection(wmOperatorType *ot)
+{
+	PropertyRNA *prop;
+
+	/* identifiers */
+	ot->name = "Link to Collection";
+	ot->description = "Link objects to a collection";
+	ot->idname = "OBJECT_OT_link_to_collection";
+
+	/* api callbacks */
+	ot->exec = move_to_collection_exec;
+	ot->invoke = move_to_collection_invoke;
+	ot->poll = ED_operator_object_active_editable;
+
+	/* flags */
+	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+
+	prop = RNA_def_int(ot->srna, "collection_index", COLLECTION_INVALID_INDEX, COLLECTION_INVALID_INDEX, INT_MAX,
+	                   "Collection Index", "Index of the collection to move to", 0, INT_MAX);
 	RNA_def_property_flag(prop, PROP_SKIP_SAVE | PROP_HIDDEN);
 	prop = RNA_def_boolean(ot->srna, "is_new", false, "New", "Move objects to a new collection");
 	RNA_def_property_flag(prop, PROP_SKIP_SAVE | PROP_HIDDEN);