question: public void addFace ( Vertex [ ] verts , Vertex [ ] norms , UV [ ] uv , Transform trans , String mtl ) { if ( uv == null ) { if ( verts . length != 4 ) throw new IllegalArgumentException ( "Default texture coordinates are only defined for quads." ) ; uv = new UV [ ] { new UV ( 0 , 0 ) , new UV ( 1 , 0 ) , new UV ( 1 , 1 ) , new UV ( 0 , 1 ) } ; } Face face = new Face ( ) ; face . uvs = uv . clone ( ) ; face . material = mtl ; face . vertices = verts . clone ( ) ; if ( norms != null ) { face . norms = norms . clone ( ) ; } if ( trans != null ) { face = trans . multiply ( face ) ; } face . chunk_idx = chunk_idx_count ; if ( Options . optimiseGeometry ) { optimisedFaces . add ( face ) ; } else { faces . add ( face ) ; } }
target:  Add a face with the given vertices to the chunk output.