为什么我画出来的海葵黑乎乎的，明明stokestyle设置成“purple”

源自：2-3 海葵绘制

aneObj.prototype.draw = function() {

ctx2.save();

ctx2.globalAlpha = 0.6;

ctx2.lineWidth = 20;

ctx2.lineCap = "round";

ctx2.stokeStyle = "purple";

for (var i = 0; i < this.num; i++) {

ctx2.beginPath();

ctx2.moveTo(this.x[i], canHeight)

ctx2.lineTo(this.x[i], canHeight - this.len[i])

ctx2.stroke();

};

ctx2.restore();

};

提问者：文文和仙仙的故事3247425 2018-03-04 18:05