BMesh: Fix for previous own fix (re-enable DynamicPaint previews in Object mode).

In fact, we have to add a CD_WEIGHT_MCOL layer (if not yet present) when updating CD_WEIGHT_MLOOPCOL, else with modifiers modifying the topology (like subsurf), it will sigsev.

That step should probably be done at tesselation time, though…

1 files changed, 7 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/dynamicpaint.c b/source/blender/blenkernel/intern/dynamicpaint.c
index 9e30003f9c7..59b7b654a45 100644
--- a/source/blender/blenkernel/intern/dynamicpaint.c
+++ b/source/blender/blenkernel/intern/dynamicpaint.c
@@ -1608,6 +1608,13 @@ static struct DerivedMesh *dynamicPaint_Modifier_apply(DynamicPaintModifierData
 							MPoly *mp = CDDM_get_polys(result);
 							int totpoly = result->numPolyData;
 
+							/* XXX We have to create a CD_WEIGHT_MCOL, else it might sigsev
+							 *     (after a SubSurf mod, eg)... */
+							if(!result->getTessFaceDataArray(result, CD_WEIGHT_MCOL)) {
+								int numFaces = result->getNumTessFaces(result);
+								CustomData_add_layer(&result->faceData, CD_WEIGHT_MCOL, CD_CALLOC, NULL, numFaces);
+							}
+
 							/* Save preview results to weight layer to be
 							*   able to share same drawing methods */
 							col = CustomData_get_layer(&result->loopData, CD_WEIGHT_MLOOPCOL);