source/blender/blenkernel/BKE_mesh.h

@@ -76,6 +76,9 @@ void BKE_mesh_tag_topology_changed(struct Mesh *mesh);
  */
 void BKE_mesh_tag_edges_split(struct Mesh *mesh);
 
+/** Call when changing "sharp_face" or "sharp_edge" data. */
+void BKE_mesh_tag_sharpness_changed(struct Mesh *mesh);
+
 /**
  * Call when face vertex order has changed but positions and faces haven't changed
  */

source/blender/blenkernel/intern/geometry_component_mesh.cc

@@ -858,10 +858,10 @@ static void tag_component_positions_changed(void *owner)
   }
 }
 
-static void tag_component_corner_normals_dirty(void *owner)
+static void tag_component_sharpness_changed(void *owner)
 {
   if (Mesh *mesh = static_cast<Mesh *>(owner)) {
-    mesh->runtime->corner_normals_cache.tag_dirty();
+    BKE_mesh_tag_sharpness_changed(mesh);
   }
 }
 
@@ -1187,7 +1187,7 @@ static ComponentAttributeProviders create_attribute_providers_for_mesh()
                                                    BuiltinAttributeProvider::Creatable,
                                                    BuiltinAttributeProvider::Deletable,
                                                    face_access,
-                                                   tag_component_corner_normals_dirty);
+                                                   tag_component_sharpness_changed);
 
   static BuiltinCustomDataLayerProvider sharp_edge("sharp_edge",
                                                    ATTR_DOMAIN_EDGE,
@@ -1196,7 +1196,7 @@ static ComponentAttributeProviders create_attribute_providers_for_mesh()
                                                    BuiltinAttributeProvider::Creatable,
                                                    BuiltinAttributeProvider::Deletable,
                                                    edge_access,
-                                                   tag_component_corner_normals_dirty);
+                                                   tag_component_sharpness_changed);
 
   static VertexGroupsAttributeProvider vertex_groups;
   static CustomDataAttributeProvider corner_custom_data(ATTR_DOMAIN_CORNER, corner_access);

source/blender/blenkernel/intern/mesh_runtime.cc

@@ -355,6 +355,11 @@ void BKE_mesh_tag_edges_split(Mesh *mesh)
   }
 }
 
+void BKE_mesh_tag_sharpness_changed(Mesh *mesh)
+{
+  mesh->runtime->corner_normals_cache.tag_dirty();
+}
+
 void BKE_mesh_tag_face_winding_changed(Mesh *mesh)
 {
   mesh->runtime->vert_normals_cache.tag_dirty();

source/blender/makesrna/intern/rna_mesh.cc

@@ -582,7 +582,10 @@ static void rna_MeshPolygon_use_smooth_set(PointerRNA *ptr, bool value)
         &mesh->face_data, CD_PROP_BOOL, CD_SET_DEFAULT, mesh->faces_num, "sharp_face"));
   }
   const int index = rna_MeshPolygon_index_get(ptr);
-  sharp_faces[index] = !value;
+  if (value != sharp_faces[index]) {
+    sharp_faces[index] = value;
+    BKE_mesh_tag_sharpness_changed(mesh);
+  }
 }
 
 static bool rna_MeshPolygon_select_get(PointerRNA *ptr)
@@ -1368,7 +1371,10 @@ static void rna_MeshEdge_use_edge_sharp_set(PointerRNA *ptr, bool value)
         &mesh->edge_data, CD_PROP_BOOL, CD_SET_DEFAULT, mesh->totedge, "sharp_edge"));
   }
   const int index = rna_MeshEdge_index_get(ptr);
-  sharp_edge[index] = value;
+  if (value != sharp_edge[index]) {
+    sharp_edge[index] = value;
+    BKE_mesh_tag_sharpness_changed(mesh);
+  }
 }
 
 static bool rna_MeshEdge_use_seam_get(PointerRNA *ptr)

source/blender/makesrna/intern/rna_mesh_api.cc

@@ -178,6 +178,7 @@ static void rna_Mesh_update(Mesh *mesh,
 
   mesh->runtime->vert_normals_cache.tag_dirty();
   mesh->runtime->face_normals_cache.tag_dirty();
+  mesh->runtime->corner_normals_cache.tag_dirty();
 
   DEG_id_tag_update(&mesh->id, 0);
   WM_event_add_notifier(C, NC_GEOM | ND_DATA, mesh);