Fix wrong edges created by split faces

We need to first split all vertices before we can reliably
check whether edge can be reused or not.

There is still known issue happening with a edge-fan mesh
with some faces being on the same plane.

1 files changed, 6 insertions, 4 deletions

diff --git a/source/blender/blenkernel/intern/mesh.c b/source/blender/blenkernel/intern/mesh.c
index 6da86e3d151..3d50b4729fb 100644
--- a/source/blender/blenkernel/intern/mesh.c
+++ b/source/blender/blenkernel/intern/mesh.c
@@ -2228,7 +2228,7 @@ void BKE_mesh_split_faces(Mesh *mesh)
 	/* Perform actual split of vertices and adjacent edges. */
 	num_new_verts = 0;
 	num_new_edges = 0;
-	/* Mapping from original vertex index to a split one. */
+	/* Insert new split vertices. */
 	for (int poly = 0; poly < num_polys; poly++) {
 		MPoly *mp = &mpoly[poly];
 		/* First we split all vertices to get proper flag whether they are
@@ -2256,9 +2256,11 @@ void BKE_mesh_split_faces(Mesh *mesh)
 				num_new_verts++;
 			}
 		}
-		/* Connect new vertices with edges. */
-		int loop_prev = mp->totloop - 1;
-		for (int loop = 0; loop < mp->totloop; loop++) {
+	}
+	/* Connect new vertices with edges. */
+	for (int poly = 0; poly < num_polys; poly++) {
+		MPoly *mp = &mpoly[poly];
+		for (int loop = 0, loop_prev = mp->totloop - 1; loop < mp->totloop; loop++) {
 			const int poly_loop_prev = mp->loopstart + loop_prev;
 			const MLoop *ml = &mloop[mp->loopstart + loop];
 			const MVert *mv = &mvert[ml->v];