Multires: Simplify reshaping code

The idea is to run reshaping for every boundary vertex
of a grid rather than trying to copy boundary grid
elements.

While this is somewhat slower, this avoids all this
tangent flipping magic, which tempts to be rather tricky
and fragile.

1 files changed, 4 insertions, 2 deletions

diff --git a/source/blender/blenkernel/BKE_multires.h b/source/blender/blenkernel/BKE_multires.h
index 7cefda3330d..f246522fffe 100644
--- a/source/blender/blenkernel/BKE_multires.h
+++ b/source/blender/blenkernel/BKE_multires.h
@@ -155,8 +155,10 @@ void BKE_multires_subdiv_mesh_settings_init(
 
 /* For a given partial derivatives of a ptex face get tangent matrix for
  * displacement.
- * Corner needs to be known to properly "rotate" partial derivatives.
- */
+ *
+ * Corner needs to be known to properly "rotate" partial derivatives when the
+ * matrix is being constructed for quad. For non-quad the corner is to be set
+ * to 0. */
 BLI_INLINE void BKE_multires_construct_tangent_matrix(
         float tangent_matrix[3][3],
         const float dPdu[3],