View Full Version : Bump (sampling?) again, question to the pro's here


jj80
12 December 2006, 12:38 AM
Hi all,

Basically, I've written a very simple "layered shader" which outputs different layers into different frameBuffers, sort of what ctrl_buffers does.

What I found now is that bump maps (at least procedurals) seem to get sampled differently depending on wether I plug my shading network into the "miMaterialShader" attribute in the Shading Group or the maya default "surfaceMaterial". Does anyone have an idea as to why this would happen ?

Please have a look at the screenshot, you'll see what I mean. I sort of feel that I still don't completely understand how mental ray handles bump mapping and what the bump mapping calculations of a lambert shader have to do with the shading group ???

It would be really cool to find out what's going on here, basically because I have to "convert" a lot of assets which previously have been rendered with MS to MR. And they more or less have to look similar...


PS: To reconstruct this, just build two similar networks, once with just simple maya nodes and one with the bump combiner in the end and compare the result...

jj80
12 December 2006, 05:58 AM
For anyone interested in an answer to this issue (thanks to Pavel aka puppet), have a look here :

http://mymentalray.com/forum/showthread.php?p=1062#post1062

CGTalk Moderation
12 December 2006, 05:58 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.


1