Fix T39781: Autosmooth feature: erroneously showing hidden vertices' normals too when in "vertex per face" display

So, turned out after all we need a foreachmapped helper for loops as well... :/

CDDM and EBDM were reasonably simple, but I fought hours with CCGDM (subsurf) to find only a
bad working solution (see D478). So I fallback to a code similar to CDDM one.
Probably not nice for performances, but loops and subsurf are not matching well...

Reviewers: campbellbarton

CC: brecht

Differential Revision: https://developer.blender.org/D478

1 files changed, 34 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/editderivedmesh.c b/source/blender/blenkernel/intern/editderivedmesh.c
index f1724553ad7..e7093d4035f 100644
--- a/source/blender/blenkernel/intern/editderivedmesh.c
+++ b/source/blender/blenkernel/intern/editderivedmesh.c
@@ -378,6 +378,39 @@ static void emDM_drawUVEdges(DerivedMesh *dm)
 	glEnd();
 }
 
+static void emDM_foreachMappedLoop(
+        DerivedMesh *dm,
+        void (*func)(void *userData, int vertex_index, int face_index, const float co[3], const float no[3]),
+        void *userData,
+        DMForeachFlag flag)
+{
+	/* We can't use dm->getLoopDataLayout(dm) here, we want to always access dm->loopData, EditDerivedBMesh would
+	 * return loop data from bmesh itself. */
+	const float (*lnors)[3] = (flag & DM_FOREACH_USE_NORMAL) ? DM_get_loop_data_layer(dm, CD_NORMAL) : NULL;
+
+	EditDerivedBMesh *bmdm = (EditDerivedBMesh *)dm;
+	BMesh *bm = bmdm->em->bm;
+	BMFace *efa;
+	BMIter iter;
+
+	const float (*vertexCos)[3] = bmdm->vertexCos;
+	int f_idx;
+
+	BM_mesh_elem_index_ensure(bm, BM_VERT);
+
+	BM_ITER_MESH_INDEX (efa, &iter, bm, BM_FACES_OF_MESH, f_idx) {
+		BMLoop *l_iter, *l_first;
+
+		l_iter = l_first = BM_FACE_FIRST_LOOP(efa);
+		do {
+			const BMVert *eve = l_iter->v;
+			const int v_idx = BM_elem_index_get(eve);
+			const float *no = lnors ? *lnors++ : NULL;
+			func(userData, v_idx, f_idx, vertexCos ? vertexCos[v_idx] : eve->co, no);
+		} while ((l_iter = l_iter->next) != l_first);
+	}
+}
+
 static void emDM_foreachMappedFaceCenter(
         DerivedMesh *dm,
         void (*func)(void *userData, int index, const float co[3], const float no[3]),
@@ -1728,6 +1761,7 @@ DerivedMesh *getEditDerivedBMesh(BMEditMesh *em,
 	bmdm->dm.recalcTessellation = emDM_recalcTessellation;
 
 	bmdm->dm.foreachMappedVert = emDM_foreachMappedVert;
+	bmdm->dm.foreachMappedLoop = emDM_foreachMappedLoop;
 	bmdm->dm.foreachMappedEdge = emDM_foreachMappedEdge;
 	bmdm->dm.foreachMappedFaceCenter = emDM_foreachMappedFaceCenter;