[Bf-blender-cvs] [f496a34] blender-v2.78-release: Fix T49220: Vertex paint doesn't work with OpenSubdiv

[Sergey Sharybin]

Commit: f496a347000c26dcbe098781c4b2ca5d5b45da58
Author: Sergey Sharybin
Date:   Fri Sep 2 15:15:42 2016 +0200
Branches: blender-v2.78-release
https://developer.blender.org/rBf496a347000c26dcbe098781c4b2ca5d5b45da58

Fix T49220: Vertex paint doesn't work with OpenSubdiv

It's a bit tricky to align vertex color data between Blender and OpenSubdiv
so for now we simply disable OpenSubdiv in the paint modes.

Safe for 2.78.

===================================================================

M	source/blender/modifiers/intern/MOD_subsurf.c

===================================================================

diff --git a/source/blender/modifiers/intern/MOD_subsurf.c b/source/blender/modifiers/intern/MOD_subsurf.c
index 23ab618..8711384 100644
--- a/source/blender/modifiers/intern/MOD_subsurf.c
+++ b/source/blender/modifiers/intern/MOD_subsurf.c
@@ -130,6 +130,9 @@ static DerivedMesh *applyModifier(ModifierData *md, Object *ob,
 		if (U.opensubdiv_compute_type == USER_OPENSUBDIV_COMPUTE_NONE) {
 			modifier_setError(md, "OpenSubdiv is disabled in User Preferences");
 		}
+		else if ((ob->mode & (OB_MODE_VERTEX_PAINT | OB_MODE_WEIGHT_PAINT | OB_MODE_TEXTURE_PAINT)) != 0) {
+			modifier_setError(md, "OpenSubdiv is not supported in paint modes");
+		}
 		else if ((DAG_get_eval_flags_for_object(md->scene, ob) & DAG_EVAL_NEED_CPU) == 0) {
 			subsurf_flags |= SUBSURF_USE_GPU_BACKEND;
 			do_cddm_convert = false;