Add tessellation data to DerivedMesh (LoopTri)

This stores loop indices into the loop array giving easier acess
to data such as vertex-colors and UV's,
removing the need to store an MFace duplicate of custom-data.

This doesn't yet move all internal code from MFace to LoopTri just yet.

Only applies to:
- opengl drawing
- sculpting (pbvh)
- vertex/weight paint

Thanks to @psy-fi for review, fixes and improvements to drawing!

1 files changed, 2 insertions, 0 deletions

diff --git a/source/blender/blenkernel/BKE_cdderivedmesh.h b/source/blender/blenkernel/BKE_cdderivedmesh.h
index 59ec316a403..c7ad6419560 100644
--- a/source/blender/blenkernel/BKE_cdderivedmesh.h
+++ b/source/blender/blenkernel/BKE_cdderivedmesh.h
@@ -125,6 +125,8 @@ void CDDM_calc_edges(struct DerivedMesh *dm);
 void CDDM_recalc_tessellation(struct DerivedMesh *dm);
 void CDDM_recalc_tessellation_ex(struct DerivedMesh *dm, const bool do_face_nor_cpy);
 
+void CDDM_recalc_looptri(struct DerivedMesh *dm);
+
 /* lowers the number of vertices/edges/faces in a CDDerivedMesh
  * the layer data stays the same size
  */