百度地图 画线设置折线点 另一方法

var start="116.399,39.910"
  for(var i=0;i<1000;i++){
    start+=(';'+(116.399+Math.random()*i/2000)+','+(39.910+Math.random()*i/2000))
  }
        var polyline = new BMap.Polyline("116.399,39.910;116.405,39.920;116.425,39.900", {strokeColor:"blue", strokeWeight:6, strokeOpacity:0.5});
        map.addOverlay(polyline);
  setTimeout(function(){polyline.setPath(start)},2000)