Merge branch 'master' into new_gfx2

modules/mol/base/pymod/export_surface.cc

@@ -62,6 +62,7 @@ void export_Surface()
     .def("GetVertex", &SurfaceHandle::GetVertex)    
     .def("FindWithin", &SurfaceHandle::FindWithin)    
     .def("Invert",&SurfaceHandle::Invert)
+    .def("IsValid",&SurfaceHandle::IsValid)
   ;
 
   def("CreateSurface",create1);

modules/mol/base/src/surface_handle.hh

@@ -70,6 +70,8 @@ public:
   // flip normals
   void Invert();
 
+  bool IsValid() const {return impl_;}
+
 private:
   impl::SurfaceImplP impl_;
 };