Select object by shader and override it with Operator

[edenexposito]

Hello!

I have 3 Arnold Shaders called : red, green, blue.

I'm testing operators and trying to find any object with "blue" shader applied and replace with a "green" shader. But not seems works, maybe I don't write correctly expression:

*.(shader == "blue")

I attach a screenshot.

What I'm doing wrong here?

Maybe with something like that in selection:

/*.(@node == 'polymesh' and shader == 'blue|standard_surface')

But no luck.

Thanks!

[Stephen.Blair]

You have to test a parameter value.

*.(@node == 'polymesh' and shader.name == 'Red')

polymesh.shader is a link to a shader node

and

a shader node has a name parameter

[peter.horvath6V6K3 · Accepted solution]

Exactly what Stephen said. Also note that the name of an Arnold shader exported from C4D has the following format:

/[material_name]|[shader_name]

Spaces and other special characters are replaced with '_'.

So assuming you have an Arnold Material named 'blue' with a standard_surface shader as the root using the default name 'standard_surface' you have to write:

*.(@node == 'polymesh' and shader.name == '/blue|standard_surface')

[edenexposito]

Works like a charm! thank you again!