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DJSmackMackey
05-25-2006, 06:33 PM
I was wondering if anyone knows how I can get Mental Ray to not use the reflection vectors of an environment map. I can do it in Maya, but not in MR. In Maya, I connect a sampler info node's Normal Camera to the reflection node's (envSphere) Ray Direction, and it works. But if I render it in MR, it doesn't work at all.

floze
05-25-2006, 06:42 PM
Hmm what's your goal, what effect do you want to achieve?

DJSmackMackey
05-25-2006, 06:45 PM
Hmm what's your goal, what effect do you want to achieve?

an ambient environment like they used in renderman in the Pearl Harbor/Jurrassic 3 paper. I keep coming back to this, just hoping I'll figure it out. I can do it in Maya, so it's no big deal, I just want to learn more about Mental Ray and this seems like as good a place as any to start learning.

floze
05-25-2006, 07:14 PM
If you want environment occlusion, why dont you use the mib_amb_occlusion or dirtmap shader, or mib_bent_normal_env respectively?

DJSmackMackey
05-25-2006, 07:23 PM
If you want environment occlusion, why dont you use the mib_amb_occlusion or dirtmap shader, or mib_bent_normal_env respectively?

No, not ambient occlusion. Ambient environment.
here, maybe this will help.
http://seanskube.com/TS_ALM.html

It's my tutorial on doing it in Maya's renderer

floze
05-25-2006, 08:01 PM
Ah.. Probably what's not working in mental ray is the flipped normal thingy... you would have to code some shader that literally does that, wouldnt be too hard I guess.
Generally the opposite normal is ommited in mental ray shaders, for performance reason. You could overcome this by writing your own light sample loop instaed of using the standard mi_sample_light call if I remember correctly.

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05-25-2006, 08:01 PM
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