Fixes for adaptive subdivision. Looks like normal maps on adaptive subdivided meshes doesn't work: https://developer.blender.org/T49159

Author: boberfly

src/GafferCycles/CyclesAttributes.cpp

@@ -61,7 +61,7 @@ CyclesAttributes::CyclesAttributes( const std::string &name )
 	attributes->addChild( new Gaffer::NameValuePlug( "ccl:is_shadow_catcher", new IECore::BoolData( false ), false, "isShadowCatcher" ) );
 
 	// Subdivision parameters
-	attributes->addChild( new Gaffer::NameValuePlug( "ccl:max_level", new IECore::IntData( 12 ), false, "maxLevel" ) );
+	attributes->addChild( new Gaffer::NameValuePlug( "ccl:max_level", new IECore::IntData( 1 ), false, "maxLevel" ) );
 	attributes->addChild( new Gaffer::NameValuePlug( "ccl:dicing_rate", new IECore::FloatData( 1.0f ), false, "dicingScale" ) );
 
 	// Color

src/GafferCycles/IECoreCyclesPreview/MeshAlgo.cpp

@@ -609,21 +609,36 @@ ccl::Mesh *convertCommon( const IECoreScene::MeshPrimitive *mesh )
 
 	// TODO: Maybe move this to attibutes so it can be shared between meshes?
 	if( ( subdivision ) && ( cmesh->subdivision_type != ccl::Mesh::SUBDIVISION_NONE ) && ( !cmesh->subd_params ) )
+	{
 		cmesh->subd_params = new ccl::SubdParams( cmesh );
+		cmesh->subd_params->test_steps = 1;
+		cmesh->subd_params->split_threshold = 1;
+		cmesh->subd_params->dicing_rate = 1.0f;
+		cmesh->subd_params->max_level = 1;
+		cmesh->subd_params->camera = NULL;
+	}
 
 	// Primitive Variables are Attributes in Cycles
 	ccl::AttributeSet& attributes = (subdivision) ? cmesh->subd_attributes : cmesh->attributes;
 
 	// Convert Normals
 	PrimitiveVariable::Interpolation nInterpolation = PrimitiveVariable::Invalid;
-	if( !triangles )
+	if( ( !triangles ) && ( mesh->interpolation() == "catmullClark" ) )
+	{
+		if( const V3fVectorData *normals = normal( mesh, nInterpolation ) )
+		{
+			ccl::Attribute *attr_N = attributes.add( nInterpolation == PrimitiveVariable::Uniform ? ccl::ATTR_STD_FACE_NORMAL : ccl::ATTR_STD_VERTEX_NORMAL, ccl::ustring("N") );
+			convertN( mesh, normals, attr_N, nInterpolation );
+		}
+	}
+	else if( !triangles )
 	{
 		if( const V3fVectorData *normals = normal( trimesh.get(), nInterpolation ) )
 		{
 			ccl::Attribute *attr_N = attributes.add( nInterpolation == PrimitiveVariable::Uniform ? ccl::ATTR_STD_FACE_NORMAL : ccl::ATTR_STD_VERTEX_NORMAL, ccl::ustring("N") );
 			convertN( trimesh.get(), normals, attr_N, nInterpolation );
 		}
-		else if( mesh->interpolation() != "catmullClark" )
+		else
 		{
 			IECoreScene::MeshNormalsOpPtr normalOp = new IECoreScene::MeshNormalsOp();
 			normalOp->inputParameter()->setValue( trimesh );

src/GafferCycles/IECoreCyclesPreview/Renderer.cpp

@@ -1215,7 +1215,7 @@ class CyclesAttributes : public IECoreScenePreview::Renderer::AttributesInterfac
 				m_visibility( ~0 ), 
 				m_useHoldout( false ), 
 				m_isShadowCatcher( false ), 
-				m_maxLevel( 12 ), 
+				m_maxLevel( 1 ), 
 				m_dicingRate( 1.0f ), 
 				m_color( Color3f( 0.0f ) ), 
 				m_dupliGenerated( V3f( 0.0f ) ),