          }
                    var color = api.visual('color');

                    return {
                        type: 'polygon',
                        shape: {
                            points: echarts.graphic.clipPointsByRect(points, {
                                x: params.coordSys.x,
                                y: params.coordSys.y,
                                width: params.coordSys.width,
                                height: params.coordSys.height
                            })
