[cocos] graphic画虚线

代码来自cocos论坛用户pencik

let cmt = this.graphics.getComponent(cc.Graphics);
let startPos = cc.v2(300, 300);
let endPos =cc.v2(608, 987);
let line = endPos.sub(startPos);
let lineLenth = line.mag();
let unitLenth = 20;
let increment = line.normalize().mul(unitLenth);
let drawLine = true;
let pos = startPos.clone();
cmt.strokeColor = cc.Color.BLUE;

for(; lineLenth > unitLenth; lineLenth -= unitLenth){
     if(drawLine){
          cmt.moveTo(pos.x, pos.y);
          pos.addSelf(increment);
          cmt.lineTo(pos.x, pos.y);
          cmt.stroke();
      }else{
            pos.addSelf(increment);
      }
      drawLine = !drawLine;
  }

//最后一段
if(drawLine){
      cmt.moveTo(pos.x, pos.y);
      cmt.lineTo(endPos.x, endPos.y);
      cmt.stroke();
}

开启抗锯齿(新建一个js文件，写入以下代码即可）
if(!CC_EDITOR){
cc.macro.ENABLE_WEBGL_ANTIALIAS = true;
}