Split Normals I (1/5): basis for split normals (nearly nothing user-visible here):

* Add a new calcLoopNormals function to DerivedMesh struct, and implement it for CDDM and CCGDM (subsurf).
  EditDerivedBMesh (edit mode DM) only gets a dummy one in this commit.
* Add a tessellated version of CD_LOOPNORMAL layer (CD_TESSLOOPNORMAL), with relevant code to handle it
  (tessellation, rna access, etc.).
* Change auto_smooth options of Mesh (angle now in radian internaly, and toggle is now used to enable/disable
  split normals in DM creation process). Note BI render code is not touched here, hence its behavior regarding
  this option is now incoherent, will be addressed in a separate commit.

Reviewers: campbellbarton

CC: brecht

Differential Revision: https://developer.blender.org/D365

1 files changed, 6 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/editderivedmesh.c b/source/blender/blenkernel/intern/editderivedmesh.c
index b7c5c605254..152540041f7 100644
--- a/source/blender/blenkernel/intern/editderivedmesh.c
+++ b/source/blender/blenkernel/intern/editderivedmesh.c
@@ -171,6 +171,11 @@ static void emDM_calcNormals(DerivedMesh *dm)
 	dm->dirty &= ~DM_DIRTY_NORMALS;
 }
 
+static void emDM_calcLoopNormals(DerivedMesh *dm, const float split_angle)
+{
+	/* Do nothing for now! */
+}
+
 static void emDM_recalcTessellation(DerivedMesh *UNUSED(dm))
 {
 	/* do nothing */
@@ -1654,6 +1659,7 @@ DerivedMesh *getEditDerivedBMesh(BMEditMesh *em,
 	bmdm->dm.getTessFaceDataArray = emDM_getTessFaceDataArray;
 
 	bmdm->dm.calcNormals = emDM_calcNormals;
+	bmdm->dm.calcLoopNormals = emDM_calcLoopNormals;
 	bmdm->dm.recalcTessellation = emDM_recalcTessellation;
 
 	bmdm->dm.foreachMappedVert = emDM_foreachMappedVert;