Fix T78242: Crash when using a Sculpt color tools that needs connectivity for the first time

When there is no color layer available,
BKE_sculpt_update_object_for_edit creates a new one and tags the mesh
with ID_RECLAC_GEOMETRY, so this layer is inmediatly available when the
tool starts. This also deletes the PBVH and when it is created again in
BKE_sculpt_update_object_after_eval, the pmap is not initialized, making
the tool crash.

This moves the color layer creation to a separate function outside
BKE_sculpt_update_object_for_edit, which now runs after the color
layer is available, so it won't need to update again and the pmap will
still be available when the tool is used.

Reviewed By: sergey

Maniphest Tasks: T78242

Differential Revision: https://developer.blender.org/D8135

1 files changed, 4 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_paint.h b/source/blender/blenkernel/BKE_paint.h
index e3a6fb4ba2e..1c02aece06f 100644
--- a/source/blender/blenkernel/BKE_paint.h
+++ b/source/blender/blenkernel/BKE_paint.h
@@ -451,6 +451,10 @@ void BKE_sculptsession_free_vwpaint_data(struct SculptSession *ss);
 void BKE_sculptsession_bm_to_me(struct Object *ob, bool reorder);
 void BKE_sculptsession_bm_to_me_for_render(struct Object *object);
 
+/* Create new color layer on object if it doesn't have one and if experimental feature set has
+ * sculpt vertex color enabled. Returns truth if new layer has been added, false otherwise. */
+void BKE_sculpt_color_layer_create_if_needed(struct Object *object);
+
 void BKE_sculpt_update_object_for_edit(struct Depsgraph *depsgraph,
                                        struct Object *ob_orig,
                                        bool need_pmap,