V-ray 2.4 displacement maping and subD problem

V-Ray V-Ray for Maya Issues
1

I have a slight problem rendering Displacement maps in Maya + Vray 2.4 Linux Centos.
I use Displacement maps from Mudbox.
These are 32bit exr. So not much setting. At least in mental ray they work. Properly.
My workflow.
I am baking 32bit displacement from mudbox tried both raycast and subdivision method. Maps are ok they sculpt properly in Mudbox and work in mental Ray.
Afterwards I plugi it into File node and than Out red Color Red chanel to the displacement node displacement value. Afterwads Displacement node into the displacement slot of the shading network. I add an attribute for the displacement node for the negative Values. For the object shape node I add displacement and subdivision controll node. Set the subdivision levels to a highest level from mudbox or a bit less for testing. Displacement Works but it doesn’t smooth the object yet. Now I turn on subdivision surfaces node and the displacement flatens. When I tick it off it works. So I crank up the mesh subdivision of the mesh in with polymodeling tool smooth a few times. Displacement works but . I turn on Subdivision surfaces and bam looks like a bump map. Also I noticed that displacement doesn’t work properly with <UDIM> <UVTile>. Command works good on diffuse and other textures but here I need to do it manualy by avarage node and setting up all the placement nodes properly. Still tested without subdivision attribute. Otherwise it looks like a bump map. So its even more flat. When using Udim tile method it avarages the values of the maps and the displecment is smaller.
I want an acurate displacement no eyeballing. In mantal ray I just plug the map into displacement slot and tick Alpha is lumminace and turn on Subdivision during rendering. It is a 32bit floating map for a reason. So I live Displacement bound at automatic and don’t touch the Displacement Amount or shift. All the info is in the file. And It works untill I turn on subdivision surfaces.

I have done some test on V-ray 3.0 and displacement has the same problems unless I use opensubdive that it is all good.

Cheeres!

2

Hi,

It will be hard to tell where is the problem without the scene file. Is it possible to attach any screenshots or even the Maya and Mudbox file?

3

I’ll do an example sceen tommorow at work both from mudbox and the way I make displacement and from Maya and I shall post it in the tread.

4

Hmm it jus works now on a other scean other project. So it might by some bug or smth…