Replace of (id->lib != NULL) check by meaningful macro.

Idea is to replace hard-to-track (id->lib != NULL) 'is linked datablock' check everywhere in Blender
by a macro doing the same thing. This will allow to easily spot those checks in future, and more importantly,
to easily change it (see work done in asset-engine branch).

Note: did not touch to readfile.c, since there most of the time 'id->lib' check actually concerns the pointer,
and not a check whether ID is linked or not. Will have a closer look at it later.

Reviewers: campbellbarton, brecht, sergey

Differential Revision: https://developer.blender.org/D2082

1 files changed, 3 insertions, 3 deletions

diff --git a/source/blender/editors/mesh/mesh_data.c b/source/blender/editors/mesh/mesh_data.c
index e0ddc017e93..772bb1bd308 100644
--- a/source/blender/editors/mesh/mesh_data.c
+++ b/source/blender/editors/mesh/mesh_data.c
@@ -511,7 +511,7 @@ static int layers_poll(bContext *C)
 {
 	Object *ob = ED_object_context(C);
 	ID *data = (ob) ? ob->data : NULL;
-	return (ob && !ob->id.lib && ob->type == OB_MESH && data && !data->lib);
+	return (ob && !ID_IS_LINKED_DATABLOCK(ob) && ob->type == OB_MESH && data && !ID_IS_LINKED_DATABLOCK(data));
 }
 
 static int mesh_uv_texture_add_exec(bContext *C, wmOperator *UNUSED(op))
@@ -759,7 +759,7 @@ static int mesh_customdata_mask_clear_poll(bContext *C)
 			return false;
 		}
 
-		if (me->id.lib == NULL) {
+		if (!ID_IS_LINKED_DATABLOCK(me)) {
 			CustomData *data = GET_CD_DATA(me, vdata);
 			if (CustomData_has_layer(data, CD_PAINT_MASK)) {
 				return true;
@@ -813,7 +813,7 @@ static int mesh_customdata_skin_state(bContext *C)
 
 	if (ob && ob->type == OB_MESH) {
 		Mesh *me = ob->data;
-		if (me->id.lib == NULL) {
+		if (!ID_IS_LINKED_DATABLOCK(me)) {
 			CustomData *data = GET_CD_DATA(me, vdata);
 			return CustomData_has_layer(data, CD_MVERT_SKIN);
 		}