Set light_color_shader through operator in houdini

[zenop]

Hi,

I'm trying to set the light_color_shader parameter (ar_light_color_shader) on a skydome through an operator. I can't seem to get it to work. I assume it's because the ar_light_color_shader is a houdini concept and gets translated to the arnold universe in a different way. I imagine 'shader' is the parameter that needs to be set.

However, I'm struggling to assign a shader to the skydome this way. How should this be set up? I'm currently seeing the pink shader not found when using a set_parameter shader with arguments: shader='/path/to/shader/OUT_light'. Should I be using the OUT_light, or OUT_material node? I cannot seem to get either to work.

When I point the the ar_light_color_shader parameter to the OUT_light node it does seem to work. But how should this be done using an operator? Maybe I'm missing something obvious.

Thanks!

[zenop · Accepted solution]

It works with an assign_material operator. Not really sure why there'd be a difference.

[Stephen.Blair]

Operators work on Arnold nodes and parameters, so a raw set_parameter won't know about ar_light_color_shader.

If you look at an ass file, you should see your shader connected to the skydome.color parameter, that's what you would set with a set_parameter

[julian.hodgson]

The assign_material operator assigns the root of the shader node graphs created by the material. This is required since these will have different names from the material itself.