OpenSubdiv: Compare edge topology

This change makes it so topology refiner comparison will check vertices
of all existing/provided edges.

The initial claim that due to manifold nature of mesh there is no need
in "deep" edges check was wrong: some areas might only provide edges
with non-zero creases. So if crease of one edge goes changes from 1.0
to 0.0 and crease of other edge goes from 0.0 to 1.0 the old comparison
code would not have caught it.

1 files changed, 15 insertions, 9 deletions

diff --git a/intern/opensubdiv/internal/topology/topology_refiner_impl_compare.cc b/intern/opensubdiv/internal/topology/topology_refiner_impl_compare.cc
index 42f7b27adab..3506d93b7aa 100644
--- a/intern/opensubdiv/internal/topology/topology_refiner_impl_compare.cc
+++ b/intern/opensubdiv/internal/topology/topology_refiner_impl_compare.cc
@@ -226,9 +226,6 @@ bool checkGeometryFacesMatch(const TopologyRefinerImpl *topology_refiner_impl,
 bool checkGeometryMatches(const TopologyRefinerImpl *topology_refiner_impl,
                           const OpenSubdiv_Converter *converter)
 {
-  // NOTE: Since OpenSubdiv's topology refiner doesn't contain loose edges, we
-  // are only checking for faces to be matched. Changes in edges we don't care
-  // here too much (they'll be checked for creases changes later).
   return checkGeometryFacesMatch(topology_refiner_impl, converter);
 }
 
@@ -279,9 +276,6 @@ bool checkUVLayersMatch(const TopologyRefinerImpl *topology_refiner_impl,
 bool checkTopologyAttributesMatch(const TopologyRefinerImpl *topology_refiner_impl,
                                   const OpenSubdiv_Converter *converter)
 {
-  if (!topology_refiner_impl->base_mesh_topology.isEqualToConverter(converter)) {
-    return false;
-  }
   return checkUVLayersMatch(topology_refiner_impl, converter);
 }
 
@@ -289,9 +283,21 @@ bool checkTopologyAttributesMatch(const TopologyRefinerImpl *topology_refiner_im
 
 bool TopologyRefinerImpl::isEqualToConverter(const OpenSubdiv_Converter *converter) const
 {
-  return (blender::opensubdiv::checkPreliminaryMatches(this, converter) &&
-          blender::opensubdiv::checkGeometryMatches(this, converter) &&
-          blender::opensubdiv::checkTopologyAttributesMatch(this, converter));
+  if (!blender::opensubdiv::checkPreliminaryMatches(this, converter)) {
+    return false;
+  }
+  if (!blender::opensubdiv::checkGeometryMatches(this, converter)) {
+    return false;
+  }
+  if (!blender::opensubdiv::checkTopologyAttributesMatch(this, converter)) {
+    return false;
+  }
+
+  if (!base_mesh_topology.isEqualToConverter(converter)) {
+    return false;
+  }
+
+  return true;
 }
 
 }  // namespace opensubdiv