It is possible to create arbitrary user data that can be attached to any object. This user data can then later be used at shading time by specific nodes with a user prefix.
- Create a 'aiUserDataFloat' in Maya and call it 'TestFloat':
- Export the scene as an .ass file and open it in a text editor. We can see that the float 'TestFloat' is stored in the .ass file as follows:
More examples on how to use these shaders can be found here.