Cleanup a bit of the locked shape keys painting

It's still gives some slowdown when painting a locked
key in the solid view, but since shape key is now longer
being re-used by DM.

but this change should still give some degree of speedup
propagating delta onto the keyblock if i remember the
code correct.

1 files changed, 16 insertions, 4 deletions

diff --git a/source/blender/editors/sculpt_paint/sculpt.c b/source/blender/editors/sculpt_paint/sculpt.c
index df7477e9583..b75387d5551 100644
--- a/source/blender/editors/sculpt_paint/sculpt.c
+++ b/source/blender/editors/sculpt_paint/sculpt.c
@@ -198,7 +198,8 @@ static bool sculpt_modifiers_active(Scene *scene, Sculpt *sd, Object *ob)
 	if (mmd || ob->sculpt->bm)
 		return 0;
 
-	if (me->key && ob->shapenr)
+	/* non-locked shape keys could be handled in the same way as deformed mesh */
+	if ((ob->shapeflag & OB_SHAPE_LOCK) == 0 && me->key && ob->shapenr)
 		return 1;
 
 	md = modifiers_getVirtualModifierList(ob, &virtualModifierData);
@@ -3423,7 +3424,7 @@ static void sculpt_flush_stroke_deform(Sculpt *sd, Object *ob)
 		MEM_freeN(nodes);
 
 		/* Modifiers could depend on mesh normals, so we should update them/
-		 * Note, then if sculpting happens on key, normals should be re-calculated
+		 * Note, then if sculpting happens on locked key, normals should be re-calculated
 		 * after applying coords from keyblock on base mesh */
 		BKE_mesh_calc_normals(me);
 	}
@@ -4465,7 +4466,7 @@ static void sculpt_flush_update(bContext *C)
 	if (ob->derivedFinal) /* VBO no longer valid */
 		GPU_drawobject_free(ob->derivedFinal);
 
-	if (ss->modifiers_active) {
+	if (ss->kb || ss->modifiers_active) {
 		DAG_id_tag_update(&ob->id, OB_RECALC_DATA);
 		ED_region_tag_redraw(ar);
 	}
@@ -4566,8 +4567,19 @@ static void sculpt_stroke_update_step(bContext *C, struct PaintStroke *UNUSED(st
 	/* hack to fix noise texture tearing mesh */
 	sculpt_fix_noise_tear(sd, ob);
 
-	if (ss->modifiers_active)
+	/* TODO(sergey): This is not really needed for the solid shading,
+	 * which does use pBVH drawing anyway, but texture and wireframe
+	 * requires this.
+	 *
+	 * Could be optimized later, but currently don't think it's so
+	 * much common scenario.
+	 **
+	 ** Same applies to the DAG_id_tag_update() invoked from
+	 * sculpt_flush_update().
+	 */
+	if (ss->kb || ss->modifiers_active) {
 		sculpt_flush_stroke_deform(sd, ob);
+	}
 
 	ss->cache->first_time = false;