[]3d点光源究竟有无衰减参数设置的？

var pointLight = scene.addChild(new Laya.PointLight());
pointLight.ambientColor = new Laya.Vector3(0.8, 0.8, 0.8);
pointLight.specularColor = new Laya.Vector3(2.0, 2.0, 0.9);
pointLight.diffuseColor = new Laya.Vector3(1, 1, 1);
pointLight.transform.translate(new Laya.Vector3(0, 30, 0));
pointLight.attenuation = new Laya.Vector3(3.0, 3.0, 3.0);
pointLight.range = 30.0;

发现是没有衰减的，一个半圆这样，跟电筒照出来的一样，好难看啊