Import Matrix User Data from C4D

[Shawn_Kearney1]

Is there any way to import a matrix from c4d user data directly? I can import vectors (or floats) and then recompose the matrix in arnold, but that seems a little wonky.

I want to translate a vector (the world shading position) to orientation of another object.

[peter.horvath6V6K3 · Accepted solution]

I'm not sure I understand your need. Altering the transformation of an object is not possible from a shading context. What would you like to achieve exactly?

[Shawn_Kearney1]

I'm trying to go the other direction, I want to transform a vector within a shader using the matrix of another object. I was trying to hack together a solution for the cloner effector to work.

Though, I recently learned about the display_color attribute so that mograph effector's color channel can be applied within arnold shaders, so this particular issue is moot. But while we're on the topic, are there any other reserved/global user data attributes? I don't remember reading about this feature in the documentation.

[peter.horvath6V6K3]

Well, we have removed the matrix type shaders in Arnold 5, but you can write a custom one in c++ to multiply a vector and a matrix.

To answer the other question, the display_color is the only custom attribute at the moment.