An example scene file can be downloaded here.

Density

Use geometry

If enabled an Arnold Light Blocker Geo object is added to the scene which allows you to easily setup object transformation and gives visual feedback of the geometry in the viewport. All geometry parameters are exported from this object. You can also assign a material to the object.

Geometry

An Arnold Light Blocker Geo object which represents the geometry of the light blocker filter.

 

Axis

Ramp

Height Edge

Width Edge

Roundness

Shader

Geometry Matrix