Can anyone think what I might have done? It was working fine and then ... no depth map shadows on hair in the Maya Software renderer. I don't know what I can have changed.
Could it be a bug? An installation issue?
I had a Maya 8.5 scene with just hair, and then I imported a rigged polygonal character from an older version of Maya. As far as I know that's when it stopped working.
Any suggestions? Something simple and stupid?