2 files changed, 20 insertions, 12 deletions
diff --git a/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc b/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc
index 0d422180288..4ced14ab11a 100644
--- a/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc
+++ b/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_edituv_stretch_angle.cc
@@ -224,6 +224,21 @@ static void extract_edituv_stretch_angle_init_subdiv(const DRWSubdivCache *subdi
   GPUVertBuf *pos_nor = cache->final.buff.vbo.pos_nor;
   GPUVertBuf *uvs = cache->final.buff.vbo.uv;
 
+  /* It may happen that the data for the UV editor is requested before (as a separate draw update)
+   * the data for the mesh when switching to the `UV Editing` workspace, and therefore the position
+   * buffer might not be created yet. In this case, create a buffer it locally, the subdivision
+   * data should already be evaluated if we are here. This can happen if the subsurf modifier is
+   * only enabled in edit-mode. See T96338. */
+  if (!pos_nor) {
+    const DRWSubdivLooseGeom &loose_geom = subdiv_cache->loose_geom;
+    pos_nor = GPU_vertbuf_calloc();
+    GPU_vertbuf_init_build_on_device(pos_nor,
+                                     draw_subdiv_get_pos_nor_format(),
+                                     subdiv_cache->num_subdiv_loops + loose_geom.loop_len);
+
+    draw_subdiv_extract_pos_nor(subdiv_cache, pos_nor);
+  }
+
   /* UVs are stored contiguously so we need to compute the offset in the UVs buffer for the active
    * UV layer. */
   CustomData *cd_ldata = (mr->extract_type == MR_EXTRACT_MESH) ? &mr->me->ldata : &mr->bm->ldata;
@@ -253,6 +268,10 @@ static void extract_edituv_stretch_angle_init_subdiv(const DRWSubdivCache *subdi
 
   draw_subdiv_build_edituv_stretch_angle_buffer(
       subdiv_cache, pos_nor, uvs, uvs_offset, refined_vbo);
+
+  if (!cache->final.buff.vbo.pos_nor) {
+    GPU_vertbuf_discard(pos_nor);
+  }
 }
 
 constexpr MeshExtract create_extractor_edituv_edituv_stretch_angle()
diff --git a/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_pos_nor.cc b/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_pos_nor.cc
index dd056891a94..ea46d9c4caa 100644
--- a/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_pos_nor.cc
+++ b/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_pos_nor.cc
@@ -179,17 +179,6 @@ static void extract_pos_nor_finish(const MeshRenderData *UNUSED(mr),
   MEM_freeN(data->normals);
 }
 
-static GPUVertFormat *get_pos_nor_format()
-{
-  static GPUVertFormat format = {0};
-  if (format.attr_len == 0) {
-    GPU_vertformat_attr_add(&format, "pos", GPU_COMP_F32, 3, GPU_FETCH_FLOAT);
-    GPU_vertformat_attr_add(&format, "nor", GPU_COMP_F32, 4, GPU_FETCH_FLOAT);
-    GPU_vertformat_alias_add(&format, "vnor");
-  }
-  return &format;
-}
-
 static GPUVertFormat *get_normals_format()
 {
   static GPUVertFormat format = {0};
@@ -221,7 +210,7 @@ static void extract_pos_nor_init_subdiv(const DRWSubdivCache *subdiv_cache,
 
   /* Initialize the vertex buffer, it was already allocated. */
   GPU_vertbuf_init_build_on_device(
-      vbo, get_pos_nor_format(), subdiv_cache->num_subdiv_loops + loose_geom.loop_len);
+      vbo, draw_subdiv_get_pos_nor_format(), subdiv_cache->num_subdiv_loops + loose_geom.loop_len);
 
   if (subdiv_cache->num_subdiv_loops == 0) {
     return;