LiveScene: Add support to read attributes from Nuke

Author: lucienfostier

src/IECoreNuke/LiveScene.cpp

@@ -44,6 +44,7 @@
 
 #include "IECore/Exception.h"
 #include "IECore/NullObject.h"
+#include "IECore/SimpleTypedData.h"
 #include "IECore/TransformationMatrixData.h"
 
 #include "OpenEXR/OpenEXRConfig.h"
@@ -81,6 +82,38 @@ IECore::TransformationMatrixd convertTransformMatrix( DD::Image::Matrix4& from )
 
 tbb::recursive_mutex g_mutex;
 
+IECore::ConstObjectPtr convertAttribute( const DD::Image::Attribute *attribute )
+{
+	switch( attribute->type() )
+	{
+		case DD::Image::FLOAT_ATTRIB :
+			return new IECore::FloatData( attribute->flt( 0 ) );
+		case DD::Image::INT_ATTRIB :
+			return new IECore::IntData( attribute->integer( 0 ) );
+		case DD::Image::STD_STRING_ATTRIB :
+			return new IECore::StringData( attribute->stdstring( 0 ) );
+		case DD::Image::STRING_ATTRIB :
+		{
+			const char *s = attribute->string( 0 );
+			return new IECore::StringData( s ? s : "" );
+		}
+		case DD::Image::VECTOR2_ATTRIB :
+			return new IECore::V2fData( IECore::convert<Imath::V2f>( attribute->vector2( 0 ) ) );
+		case DD::Image::VECTOR3_ATTRIB :
+			return new IECore::V3fData( IECore::convert<Imath::V3f>( attribute->vector3( 0 ) ) );
+		case DD::Image::NORMAL_ATTRIB :
+			return new IECore::V3fData( IECore::convert<Imath::V3f>( attribute->normal( 0 ) ) );
+		case DD::Image::VECTOR4_ATTRIB :
+			return new IECore::Color4fData( IECore::convert<Imath::Color4f>( attribute->vector4( 0 ) ) );
+		case DD::Image::MATRIX3_ATTRIB :
+			return new IECore::M33fData( IECore::convert<Imath::M33f>( attribute->matrix3( 0 ) ) );
+		case DD::Image::MATRIX4_ATTRIB :
+			return new IECore::M44fData( IECore::convert<Imath::M44f>( attribute->matrix4( 0 ) ) );
+		default :
+			return nullptr;
+	}
+}
+
 LiveScene::LiveSceneGeometryCache &cachedGeometryListMap()
 {
 	static LiveScene::LiveSceneGeometryCache *cache = new LiveScene::LiveSceneGeometryCache();
@@ -424,15 +457,85 @@ void LiveScene::writeTransform( const Data *transform, double time )
 
 bool LiveScene::hasAttribute( const Name &name ) const
 {
+	const unsigned numObjects = objectNum();
+	for( unsigned i = 0; i < numObjects; ++i )
+	{
+		if( m_pathMatcher.match( geoInfoPath( i ) ) != IECore::PathMatcher::ExactMatch )
+		{
+			continue;
+		}
+		auto geoInfo = object( i );
+		if( !geoInfo )
+		{
+			return false;
+		}
+		// we only support Group_Object because they are only one that makes sense to match to IECoreScene Attributes
+		// other type of attributes are more akin to PrimitiveVariables
+		// so we could consider adding support for Group_Primitive/Vertex and Point as such.
+		auto attr = geoInfo->get_group_attribute( GroupType::Group_Object, name.c_str() );
+		return attr && attr->size() > 0;
+	}
 	return false;
 }
 
 void LiveScene::attributeNames( NameList &attrs ) const
 {
+	attrs.clear();
+	const unsigned numObjects = objectNum();
+	for( unsigned i = 0; i < numObjects; ++i )
+	{
+		if( m_pathMatcher.match( geoInfoPath( i ) ) != IECore::PathMatcher::ExactMatch )
+		{
+			continue;
+		}
+		auto geoInfo = object( i );
+		if( !geoInfo )
+		{
+			return;
+		}
+		const int count = geoInfo->get_attribcontext_count();
+		for( int j = 0; j < count; ++j )
+		{
+			auto context = geoInfo->get_attribcontext( j );
+			// we only support Group_Object because they are only one that makes sense to match to IECoreScene Attributes
+			// other type of attributes are more akin to PrimitiveVariables
+			// so we could consider adding support for Group_Primitive/Vertex and Point as such.
+			if( context && !context->empty() && context->group == GroupType::Group_Object && context->name )
+			{
+				attrs.push_back( context->name );
+			}
+		}
+		return;
+	}
 }
 
 ConstObjectPtr LiveScene::readAttribute( const Name &name, double time ) const
 {
+	const unsigned numObjects = objectNum( &time );
+	for( unsigned i = 0; i < numObjects; ++i )
+	{
+		if( m_pathMatcher.match( geoInfoPath( i ) ) != IECore::PathMatcher::ExactMatch )
+		{
+			continue;
+		}
+		auto geoInfo = object( i, &time );
+		if( !geoInfo )
+		{
+			return IECore::NullObject::defaultNullObject();
+		}
+		// we only support Group_Object because they are only one that makes sense to match to IECoreScene Attributes
+		// other type of attributes are more akin to PrimitiveVariables
+		// so we could consider adding support for Group_Primitive/Vertex and Point as such.
+		auto attr = geoInfo->get_group_attribute( GroupType::Group_Object, name.c_str() );
+		if( attr && attr->size() > 0 )
+		{
+			if( auto converted = convertAttribute( attr ) )
+			{
+				return converted;
+			}
+		}
+		return IECore::NullObject::defaultNullObject();
+	}
 	return IECore::NullObject::defaultNullObject();
 }
 

test/IECoreNuke/LiveSceneKnobTest.py

@@ -445,6 +445,72 @@ def testReadObjectMesh(self):
 		obj = child.readObject(0)
 		self.assertIsInstance(obj, IECoreScene.MeshPrimitive)
 
+	def testEmptySceneAttributes( self ) :
+
+		n = nuke.createNode( "ieLiveScene" )
+		liveScene = n.knob( "scene" ).getValue()
+
+		self.assertEqual( liveScene.attributeNames(), [] )
+		self.assertFalse( liveScene.hasAttribute( "ieName" ) )
+		self.assertFalse( liveScene.hasAttribute( "nonExistent" ) )
+		self.assertTrue( isinstance( liveScene.readAttribute( "nonExistent", 0 ), IECore.NullObject ) )
+
+	def testAttributes( self ) :
+		import imath
+		import IECoreScene
+
+		sceneFile = "test/IECoreNuke/scripts/data/liveSceneData.scc"
+		sceneReader = nuke.createNode( "ieSceneCacheReader" )
+		sceneReader.knob( "file" ).setValue( sceneFile )
+
+		sceneReader.forceValidate()
+		widget = sceneReader.knob( "sceneView" )
+		widget.setSelectedItems( ['/root/A/a', '/root/B/b'] )
+
+		n = nuke.createNode( "ieLiveScene" )
+		n.setInput( 0, sceneReader )
+
+		liveScene = n.knob( "scene" ).getValue()
+
+		# Root and parent locations have no matching GeoInfo, so no attributes.
+		self.assertEqual( liveScene.attributeNames(), [] )
+		self.assertFalse( liveScene.hasAttribute( "ieName" ) )
+
+		for subPath in ( ["A"], ["B"] ) :
+			subScene = liveScene.scene( subPath )
+			self.assertEqual( subScene.attributeNames(), [] )
+			self.assertFalse( subScene.hasAttribute( "ieName" ) )
+
+		# Leaf locations have Group_Object attributes set by ToNukeGeometryConverter.
+		leafA = liveScene.scene( ["A", "a"] )
+		self.assertIn( "ieName", leafA.attributeNames() )
+		self.assertTrue( leafA.hasAttribute( "ieName" ) )
+		self.assertFalse( leafA.hasAttribute( "nonExistent" ) )
+		self.assertIsInstance( leafA.readAttribute( "nonExistent", 0 ), IECore.NullObject )
+
+		nameAttr = leafA.readAttribute( "ieName", 0 )
+		self.assertIsInstance( nameAttr, IECore.StringData )
+		self.assertEqual( nameAttr.value, "/A/a" )
+
+		leafB = liveScene.scene( ["B", "b"] )
+		nameAttr = leafB.readAttribute( "ieName", 0 )
+		self.assertIsInstance( nameAttr, IECore.StringData )
+		self.assertEqual( nameAttr.value, "/B/b" )
+
+		# Scene attributes from the SCC round-trip through Nuke as Group_Object attributes.
+		self.assertIn( "user:Mref", leafA.attributeNames() )
+		self.assertTrue( leafA.hasAttribute( "user:Mref" ) )
+
+		# The SCC stores M44dData but Nuke round-trips it as M44fData.
+		expectedScene = IECoreScene.SharedSceneInterfaces.get( sceneFile )
+		expectedLeaf = expectedScene.scene( ["A", "a"] )
+		expectedAttr = expectedLeaf.readAttribute( "user:Mref", 0.5 )
+
+		attr = leafA.readAttribute( "user:Mref", 0 )
+		self.assertIsInstance( attr, IECore.M44fData )
+		self.assertEqual( attr.value, imath.M44f( expectedAttr.value ) )
+
+
 if __name__ == "__main__":
 	unittest.main()