[MtoA] [SItoA] Setting multiple Arnold parameters with the User Options

If you need to set multiple parameters in the User Options, you can use whitespace (spaces, tabs, and newlines) as delimiters to separate parameter statements. For example:

enable_procedural_cache off error_color_bad_pixel 1 .25 1 declare test constant FLOAT test 2
enable_procedural_cache off\n error_color_bad_pixel 1 .25\n declare test constant FLOAT\n test 2

Per-object AA settings?

In the comments, a reader asks:

I am trying to override AA_samples per geometry and cant figure out where to add the attribute. I tried adding a user option to a set with AA_samples 6 and numerous other things but to no avail. Any ideas??

That’s not the way Arnold rolls 🙂

Arnold currently uses a global, non-progressive AA scheme, and the official Arnold shaders (such as the Standard shader) don’t support per-shader or per-object sample settings. One of the goals of the Arnold renderer is to reduce the amount of controls, and per-object or per-shader sampling doesn’t really fit into that vision.

A possible workaround would be to write a custom shader that reads user data attributes from objects and overrides the sampling settings.

PS If you want to know what user options are available, try using kick -info. For example, kick -info polymesh will give you the available parameters for a polymesh node. And kick -nodes will give you a list of nodes.

Using environment variables in Arnold search paths

To use an environment variable in one of the Arnold search paths, you just have to put the environment variable in square brackets [ ].


A search path can include many paths; just use a semi-colon (;) to separate each path. For example, here’s a search path that includes three different locations: