static void AppendGeometryCollection ( const [UGeometryCollection](API\Runtime\GeometryCollectionEngine\GeometryCollection\UGeometryCollection) * SourceGeometryCollection, const [UGeometryCollectionComponent](API\Runtime\GeometryCollectionEngine\GeometryCollection\UGeometryCollect-) * GeometryCollectionComponent, const FTransform & GeometryCollectionTransform, [UGeometryCollection](API\Runtime\GeometryCollectionEngine\GeometryCollection\UGeometryCollection) * TargetGeometryCollectionObject, bool ReindexMaterials )