Mesh: Add an explicit "positions changed" function

We store various lazily calculated caches on meshes, some of which
depend on the vertex positions staying the same. The current API to
invalidate these caches is a bit confusing. With an explicit set of
functions modeled after the functions in `BKE_node_tree_update.h`,
it becomes clear which function to call. This may become more
important if more lazy caches are added in the future.

Differential Revision: https://developer.blender.org/D14760

1 files changed, 20 insertions, 5 deletions

diff --git a/source/blender/blenkernel/intern/mesh_runtime.cc b/source/blender/blenkernel/intern/mesh_runtime.cc
index 90e9a2a2ff6..d4bc47d5fd4 100644
--- a/source/blender/blenkernel/intern/mesh_runtime.cc
+++ b/source/blender/blenkernel/intern/mesh_runtime.cc
@@ -244,11 +244,8 @@ bool BKE_mesh_runtime_clear_edit_data(Mesh *mesh)
 
 void BKE_mesh_runtime_clear_geometry(Mesh *mesh)
 {
-  if (mesh->runtime.bvh_cache) {
-    bvhcache_free(mesh->runtime.bvh_cache);
-    mesh->runtime.bvh_cache = nullptr;
-  }
-  MEM_SAFE_FREE(mesh->runtime.looptris.array);
+  BKE_mesh_tag_coords_changed(mesh);
+
   /* TODO(sergey): Does this really belong here? */
   if (mesh->runtime.subdiv_ccg != nullptr) {
     BKE_subdiv_ccg_destroy(mesh->runtime.subdiv_ccg);
@@ -259,6 +256,24 @@ void BKE_mesh_runtime_clear_geometry(Mesh *mesh)
   MEM_SAFE_FREE(mesh->runtime.subsurf_face_dot_tags);
 }
 
+void BKE_mesh_tag_coords_changed(Mesh *mesh)
+{
+  BKE_mesh_normals_tag_dirty(mesh);
+  MEM_SAFE_FREE(mesh->runtime.looptris.array);
+  if (mesh->runtime.bvh_cache) {
+    bvhcache_free(mesh->runtime.bvh_cache);
+    mesh->runtime.bvh_cache = nullptr;
+  }
+}
+
+void BKE_mesh_tag_coords_changed_uniformly(Mesh *mesh)
+{
+  BKE_mesh_tag_coords_changed(mesh);
+  /* The normals didn't change, since all vertices moved by the same amount. */
+  BKE_mesh_poly_normals_clear_dirty(mesh);
+  BKE_mesh_vertex_normals_clear_dirty(mesh);
+}
+
 /** \} */
 
 /* -------------------------------------------------------------------- */