Fix T97469: Sculpt colors crash in multiresolution or dynamic topology modes.

Sculpt paint tools now pop up an error message if
dynamic topology or multires are enabled.

Implementation notes:

* SCULPT_vertex_colors_poll is now a static function in sculpt_ops.c.
  It is now used solely by the legacy color attribute conversion
  operators (SCULPT_OT_vertex_to_loop_colors and SCULPT_OT_loop_to_vertex_colors)
  and should be deleted when they are.
* There is a new method, SCULPT_handles_colors_report, that returns true if
  the sculpt session can handle color attributes; otherwise it returns false
  and displays an error message to the user.

1 files changed, 11 insertions, 1 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt_intern.h b/source/blender/editors/sculpt_paint/sculpt_intern.h
index bd95bb4666b..f13f1c79a7a 100644
--- a/source/blender/editors/sculpt_paint/sculpt_intern.h
+++ b/source/blender/editors/sculpt_paint/sculpt_intern.h
@@ -782,7 +782,17 @@ bool SCULPT_mode_poll_view3d(struct bContext *C);
 bool SCULPT_poll(struct bContext *C);
 bool SCULPT_poll_view3d(struct bContext *C);
 
-bool SCULPT_vertex_colors_poll(struct bContext *C);
+/**
+ * Returns true if sculpt session can handle color attributes
+ * (BKE_pbvh_type(ss->pbvh) == PBVH_FACES).  If false an error
+ * message will be shown to the user.  Operators should return
+ * OPERATOR_CANCELLED in this case.
+ *
+ * NOTE: Does not check if a color attribute actually exists.
+ * Calling code must handle this itself; in most cases a call to
+ * BKE_sculpt_color_layer_create_if_needed() is sufficient.
+ */
+bool SCULPT_handles_colors_report(struct SculptSession *ss, struct ReportList *reports);
 
 /** \} */