Topic: version 4 MAXScript Language Improvements / Material Editor, Material and Textures
The material-level show-in-viewport state is now also accessible as a new property on materials, .showInViewport, which can also be set on a material constructor call using the showInViewport: keyword argument.
Example:
b=box()
b.material = standard diffuseMap:(checker()) showInViewport:true
See also