Fix T99196: sculpt_update_object calls paint updates for nonpaint tools

Specifically BKE_texpaint_slots_refresh_object was being called, which
causes cycles to reset at strange times (like moving the mouse cursor
in pose, boundary and various other tools).

This (along with some code that checks if the pbvh pixels need
to be rebuilt) is only run if is_paint_mode (which used to be
needs_colors) is true.

3 files changed, 27 insertions, 23 deletions

diff --git a/source/blender/blenkernel/intern/paint.c b/source/blender/blenkernel/intern/paint.c
index 5d4a818b7e2..89cc25b31e6 100644
--- a/source/blender/blenkernel/intern/paint.c
+++ b/source/blender/blenkernel/intern/paint.c
@@ -1773,28 +1773,31 @@ static void sculpt_update_object(Depsgraph *depsgraph,
     }
   }
 
-  /*
-   * We should rebuild the PBVH_pixels when painting canvas changes.
-   *
-   * The relevant changes are stored/encoded in the paint canvas key.
-   * These include the active uv map, and resolutions.
-   */
-  if (U.experimental.use_sculpt_texture_paint && ss->pbvh) {
-    char *paint_canvas_key = BKE_paint_canvas_key_get(&scene->toolsettings->paint_mode, ob);
-    if (ss->last_paint_canvas_key == NULL || !STREQ(paint_canvas_key, ss->last_paint_canvas_key)) {
-      MEM_SAFE_FREE(ss->last_paint_canvas_key);
-      ss->last_paint_canvas_key = paint_canvas_key;
-      BKE_pbvh_mark_rebuild_pixels(ss->pbvh);
-    }
-    else {
-      MEM_freeN(paint_canvas_key);
+  if (is_paint_tool) {
+    /*
+     * We should rebuild the PBVH_pixels when painting canvas changes.
+     *
+     * The relevant changes are stored/encoded in the paint canvas key.
+     * These include the active uv map, and resolutions.
+     */
+    if (U.experimental.use_sculpt_texture_paint && ss->pbvh) {
+      char *paint_canvas_key = BKE_paint_canvas_key_get(&scene->toolsettings->paint_mode, ob);
+      if (ss->last_paint_canvas_key == NULL ||
+          !STREQ(paint_canvas_key, ss->last_paint_canvas_key)) {
+        MEM_SAFE_FREE(ss->last_paint_canvas_key);
+        ss->last_paint_canvas_key = paint_canvas_key;
+        BKE_pbvh_mark_rebuild_pixels(ss->pbvh);
+      }
+      else {
+        MEM_freeN(paint_canvas_key);
+      }
     }
-  }
 
-  /* We could be more precise when we have access to the active tool. */
-  const bool use_paint_slots = (ob->mode & OB_MODE_SCULPT) != 0;
-  if (use_paint_slots) {
-    BKE_texpaint_slots_refresh_object(scene, ob);
+    /* We could be more precise when we have access to the active tool. */
+    const bool use_paint_slots = (ob->mode & OB_MODE_SCULPT) != 0;
+    if (use_paint_slots) {
+      BKE_texpaint_slots_refresh_object(scene, ob);
+    }
   }
 }
 
diff --git a/source/blender/editors/sculpt_paint/paint_vertex.cc b/source/blender/editors/sculpt_paint/paint_vertex.cc
index c93b0fc3aa8..6dc8375bb0d 100644
--- a/source/blender/editors/sculpt_paint/paint_vertex.cc
+++ b/source/blender/editors/sculpt_paint/paint_vertex.cc
@@ -1176,12 +1176,12 @@ static void vertex_paint_init_session(Depsgraph *depsgraph,
   BLI_assert(ob->sculpt == nullptr);
   ob->sculpt = (SculptSession *)MEM_callocN(sizeof(SculptSession), "sculpt session");
   ob->sculpt->mode_type = object_mode;
-  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, false, false);
+  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, false, true);
 }
 
 static void vwpaint_init_stroke(Depsgraph *depsgraph, Object *ob)
 {
-  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, false, false);
+  BKE_sculpt_update_object_for_edit(depsgraph, ob, true, false, true);
   SculptSession *ss = ob->sculpt;
 
   /* Ensure ss->cache is allocated.  It will mostly be initialized in
diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index a3e2678aa40..906c4fd35fe 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -5081,7 +5081,8 @@ static void sculpt_brush_stroke_init(bContext *C, wmOperator *op)
   /* CTX_data_ensure_evaluated_depsgraph should be used at the end to include the updates of
    * earlier steps modifying the data. */
   Depsgraph *depsgraph = CTX_data_ensure_evaluated_depsgraph(C);
-  BKE_sculpt_update_object_for_edit(depsgraph, ob, need_pmap, need_mask, needs_colors);
+  BKE_sculpt_update_object_for_edit(
+      depsgraph, ob, need_pmap, need_mask, SCULPT_tool_is_paint(brush->sculpt_tool));
 
   ED_paint_tool_update_sticky_shading_color(C, ob);
 }