MeshPrimitive : Interpolation should not be included in the topologyHash

If two meshes differ only by interpolation, primvars can still be transferred directly, so it doesn't make sense to say they have different topologies
ImageEngine · Apr 17, 2024 · d806ff9 · d806ff9
1 parent a9b572f
commit d806ff9
Show file tree

Hide file tree

Showing 2 changed files with 2 additions and 2 deletions.
diff --git a/src/IECoreScene/MeshPrimitive.cpp b/src/IECoreScene/MeshPrimitive.cpp
@@ -525,13 +525,13 @@ void MeshPrimitive::hash( MurmurHash &h ) const
 	m_creaseLengths->hash( h );
 	m_creaseIds->hash( h );
 	m_creaseSharpnesses->hash( h );
+	h.append( m_interpolation );
 }
 
 void MeshPrimitive::topologyHash( MurmurHash &h ) const
 {
 	m_verticesPerFace->hash( h );
 	m_vertexIds->hash( h );
-	h.append( m_interpolation );
 }
 
 MeshPrimitivePtr MeshPrimitive::createBox( const Box3f &b )

diff --git a/test/IECoreScene/MeshPrimitive.py b/test/IECoreScene/MeshPrimitive.py
@@ -227,7 +227,7 @@ def testHash( self ) :
 
 		m.setTopology( IECore.IntVectorData( [ 3 ] ), IECore.IntVectorData( [ 0, 2, 1 ] ), "catmullClark" )
 		self.assertNotEqual( m.hash(), h )
-		self.assertNotEqual( m.topologyHash(), t )
+		self.assertEqual( m.topologyHash(), t )
 		h = m.hash()
 		t = m.topologyHash()