1 files changed, 67 insertions, 0 deletions

diff --git a/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_orco.cc b/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_orco.cc
index d4c801ab066..ed1a0ccd178 100644
--- a/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_orco.cc
+++ b/source/blender/draw/intern/mesh_extractors/extract_mesh_vbo_orco.cc
@@ -7,6 +7,8 @@
 
 #include "extract_mesh.h"
 
+#include "draw_subdivision.h"
+
 namespace blender::draw {
 
 /* ---------------------------------------------------------------------- */
@@ -77,12 +79,77 @@ static void extract_orco_iter_poly_mesh(const MeshRenderData *mr,
   }
 }
 
+static void extract_orco_init_subdiv(const DRWSubdivCache *subdiv_cache,
+                                     const MeshRenderData *mr,
+                                     struct MeshBatchCache *UNUSED(cache),
+                                     void *buffer,
+                                     void *UNUSED(data))
+{
+  static GPUVertFormat format = {0};
+  if (format.attr_len == 0) {
+    /* FIXME(fclem): We use the last component as a way to differentiate from generic vertex
+     * attributes. This is a substantial waste of video-ram and should be done another way.
+     * Unfortunately, at the time of writing, I did not found any other "non disruptive"
+     * alternative. */
+    GPU_vertformat_attr_add(&format, "orco", GPU_COMP_F32, 4, GPU_FETCH_FLOAT);
+  }
+
+  GPUVertBuf *dst_buffer = static_cast<GPUVertBuf *>(buffer);
+  GPU_vertbuf_init_build_on_device(dst_buffer, &format, subdiv_cache->num_subdiv_loops);
+
+  GPUVertBuf *coarse_vbo = GPU_vertbuf_calloc();
+  /* Dynamic as we upload and interpolate layers one at a time. */
+  GPU_vertbuf_init_with_format_ex(coarse_vbo, &format, GPU_USAGE_DYNAMIC);
+  GPU_vertbuf_data_alloc(coarse_vbo, mr->loop_len);
+
+  float(*coarse_vbo_data)[4] = static_cast<float(*)[4]>(GPU_vertbuf_get_data(coarse_vbo));
+
+  CustomData *cd_vdata = &mr->me->vdata;
+  float(*orco)[3] = static_cast<float(*)[3]>(CustomData_get_layer(cd_vdata, CD_ORCO));
+
+  if (mr->extract_type == MR_EXTRACT_MESH) {
+    const MLoop *mloop = mr->mloop;
+    const MPoly *mp = mr->mpoly;
+
+    int ml_index = 0;
+    for (int i = 0; i < mr->poly_len; i++, mp++) {
+      const MLoop *ml = &mloop[mp->loopstart];
+
+      for (int j = 0; j < mp->totloop; j++, ml++, ml_index++) {
+        float *loop_orco = coarse_vbo_data[ml_index];
+        copy_v3_v3(loop_orco, orco[ml->v]);
+        loop_orco[3] = 0.0; /* Tag as not a generic attribute. */
+      }
+    }
+  }
+  else {
+    BMIter iter;
+    BMFace *f;
+    BM_ITER_MESH (f, &iter, mr->bm, BM_FACES_OF_MESH) {
+      BMLoop *l_iter;
+      BMLoop *l_first;
+      l_iter = l_first = BM_FACE_FIRST_LOOP(f);
+      do {
+        const int l_index = BM_elem_index_get(l_iter);
+        float *loop_orco = coarse_vbo_data[l_index];
+        copy_v3_v3(loop_orco, orco[BM_elem_index_get(l_iter->v)]);
+        loop_orco[3] = 0.0; /* Tag as not a generic attribute. */
+      } while ((l_iter = l_iter->next) != l_first);
+    }
+  }
+
+  draw_subdiv_interp_custom_data(subdiv_cache, coarse_vbo, dst_buffer, 4, 0, false);
+
+  GPU_vertbuf_discard(coarse_vbo);
+}
+
 constexpr MeshExtract create_extractor_orco()
 {
   MeshExtract extractor = {nullptr};
   extractor.init = extract_orco_init;
   extractor.iter_poly_bm = extract_orco_iter_poly_bm;
   extractor.iter_poly_mesh = extract_orco_iter_poly_mesh;
+  extractor.init_subdiv = extract_orco_init_subdiv;
   extractor.data_type = MR_DATA_NONE;
   extractor.data_size = sizeof(MeshExtract_Orco_Data);
   extractor.use_threading = true;