I haven’t used Zbrush with Mental Ray in a while and I can’t get displacements working right. My Renderman workflow is fine but Mental Ray is all messed up in Maya 2012 and 2013 on Mac. It won’t even read my tiff files from ZBrush and I have to use HDR files. Very weird. I even tried freeing up all permissions for the project folder and enclosed items.
I have my UVs unsmoothed for mental ray, I have my multi quadrants piped into a +/- node, then into a RGB to luminance and then into the displacement value.
I also tried single maps going right into the displacement node.
I tried GoZ and .ma export but they no longer seem to export shader networks.
The model is not even subdividing all the way using a displacement approximation set to spatial/fine and 0/5 with length of .1
I scoured the net and the forums but didn’t see anyone else with these problems and I tried all the methods I know of for displacement. I even tried vector displacement but that just crashes maya.