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, 2 insertions, 2 deletions

diff --git a/source/blender/makesrna/intern/rna_object.c b/source/blender/makesrna/intern/rna_object.c
index a7f5c21cc76..5dc4bbd83dd 100644
--- a/source/blender/makesrna/intern/rna_object.c
+++ b/source/blender/makesrna/intern/rna_object.c
@@ -718,10 +718,10 @@ static int rna_Object_active_material_editable(PointerRNA *ptr)
 	bool is_editable;
 
 	if ((ob->matbits == NULL) || (ob->actcol == 0) || ob->matbits[ob->actcol - 1]) {
-		is_editable = (ob->id.lib == NULL);
+		is_editable = !ID_IS_LINKED_DATABLOCK(ob);
 	}
 	else {
-		is_editable = ob->data ? (((ID *)ob->data)->lib == NULL) : false;
+		is_editable = ob->data ? !ID_IS_LINKED_DATABLOCK(ob->data) : false;
 	}
 
 	return is_editable ? PROP_EDITABLE : 0;