ZBrushCentral

Maya 6.0 Normal Map Problem

ZBrush Usage Questions
#1

Has anyone else had a problem with getting their model just turning black when Maya 6.0’s “High Quality Rendering” is turned on?

Basically, I made a human low poly character in Maya (with separate uv’s in separate regions for the head and body), brought it into Zbrush 2 and added my high poly details to it. I then exported the normal maps (they appears to be a good normal map, and the same as what Maya’s built in plug-in derives).

I apply the normal maps out color the their respective shader’s camera normal nodes. I apply the two shaders (no other maps on them than the normals), and when I turn on “High Quality Rendering” to see the normals in the viewport I just have my model turn black. It seems that if I rotate around the model I can see the normal details, but it is black instead of the gray I would expect from a shader with no color map assigned.

Also, I’ve tried this one two different machines. The home machine has a Geforce 6800 and the work machine is a Quadro 1000 series. Both have the exact same problem so I don’t know that it would be a video card issue.

Any help with this would be greatly appreciated. Let me know if any other information would help diagnosing the problem.

#2

Can you clarify what you mean by “I apply the two shaders”? You should only have to apply one shader that contains both the normalmap and the colormap. I haven’t had any problems viewing normalmaps, but I remember a coworker not getting it to work on his machine. If you were only using a FX card I’d say that it isn’t fully OpenGL compliant and could be the problem, but a Quadro should definitely be able to show the model correctly.

#3

I thought I had made it clear, but there is a shader on the head and another shader for the rest of the body. My character is basically a nude male and for my uses needs to be one continuous piece of geometry (no edge or texture seams).

I found out the problem with Maya if anyone is interested. Basically Maya still has problems displaying characters with multiple shader networks. The workaround is to extract and separate each piece of geometry that uses a different shader (i.e. extract and separate head from body). Then apply the respective shaders to those body parts. The normals should be working correctly now. Then you can combine and merge the border edges to get the geometry back to one piece so there are no hard edge seams.

This should make the normals work if your version of Maya and video card will be able to display high quality rendering. It’s kinda silly this workaround is need, especially since Alias said they fixed it in Maya 4.0.

I hope this helps other Maya users.

#4

It sounded to me as if you had applied one shader for the colormap and then an additional shader for the normalmap (for example through a 2nd UV set), that’s why I was asking.

Thanks for the tip about multiple shaders on the same mesh, that’ll help me anticipate problems when dealing with future models!