houdini已放弃2

1.shader->procedural(evaluated during rendering and bound to surface shader parameters of the same name.)

vex volume proecdural node

If you are rendering isosurfaces, you should define a "density" export from the shader since mantra relies on this field being present for isosurface root finding.

把bego读回来，设置bound,不然选出来有的时候只能看到bound，

先 设置vex volume procedural,这个相当与调用接口，类似与中间件，Geo通过它调用然后用CVEX Shader Builder。CVEX Shader Builder，类似与一个运行容器，它能把你再其中做的操作运行起来。

可以再CVEX Shader Builder内部执行操作，

加了噪波，

随便建一个体积材质加上去，然后把materidal、procedural shader填上去。

2.照明循环 illuminance