Fix T63283: Second subdivision modifier does not ignore crease

This is something where there is no single correct behavior,
sometimes it's needed to ignore the crease to make mesh more
smooth. But sometimes crease is to be considered after first
subdivision surface: for example, when adding extra subdivisions
for render-time displacement.

Made it an option whether modifier needs to take crease into
account or not.

Existing files should be openable in the 2.7 compatible way,
to re-create an old behavior the options is to be manually
disabled in the modifier settings.

Reviewers: brecht

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D4652

1 files changed, 8 insertions, 1 deletions

diff --git a/source/blender/blenkernel/intern/subdiv_converter_mesh.c b/source/blender/blenkernel/intern/subdiv_converter_mesh.c
index 00a2436098e..eda6b522b85 100644
--- a/source/blender/blenkernel/intern/subdiv_converter_mesh.c
+++ b/source/blender/blenkernel/intern/subdiv_converter_mesh.c
@@ -168,6 +168,9 @@ static float get_edge_sharpness(const OpenSubdiv_Converter *converter,
 		return 10.0f;
 	}
 #endif
+	if (!storage->settings.use_creases) {
+		return 0.0f;
+	}
 	const int edge_index =
 	        storage->manifold_edge_index_reverse[manifold_edge_index];
 	const MEdge *medge = storage->mesh->medge;
@@ -190,9 +193,13 @@ static bool is_infinite_sharp_vertex(const OpenSubdiv_Converter *converter,
 	                            vertex_index);
 }
 
-static float get_vertex_sharpness(const OpenSubdiv_Converter *UNUSED(converter),
+static float get_vertex_sharpness(const OpenSubdiv_Converter *converter,
                                   int UNUSED(manifold_vertex_index))
 {
+	ConverterStorage *storage = converter->user_data;
+	if (!storage->settings.use_creases) {
+		return 0.0f;
+	}
 	return 0.0f;
 }