Is there any way of passing the direction option from area lights to mental ray? This is especially problematic in the case of discs and grids where you really don't want them shooting rays in all directions. Also, as a note, when selecting a disk area light the wrangler passes “disk” rather than “disc” to the mi file, creating a syntax error.

Chris

drexel
Is there any way of passing the direction option from area lights to mental ray? This is especially problematic in the case of discs and grids where you really don't want them shooting rays in all directions. Also, as a note, when selecting a disk area light the wrangler passes “disk” rather than “disc” to the mi file, creating a syntax error.

Chris

I've fixed the “disc”/“disk” issue for tomorrow's build.

However, I'm not sure about the “direction” option on area light sources. In my experience, enabling the “direction” option turns the light into an infinite/directional light source, and so, there doesn't seem to be any difference between that light and a directional/infinite light source.

Can you give me an example where this would be needed? The orientation of the light source determines the orientation of the area shape…

In my experience, enabling the “direction” option turns the light into an infinite/directional light source, and so, there doesn't seem to be any difference between that light and a directional/infinite light source.

Absolutely…this was my knee-jerk reaction to a completely unrelated issue (and rusty mi syntax), apologies.

Another unrelated issue has to deal with materials, though. First, when creating a material with both surface and photon shaders, the photon shader is placed first in the material block, so mr seems to ignore the surface. And, when using material SOPs to provide material changes on a group basis, a “# Per-primitive material” line is placed in the mi, but it doesn't seem to respect any material after the initial one.

Sorry for the flurry of issues,
Chris

drexel
Absolutely…this was my knee-jerk reaction to a completely unrelated issue (and rusty mi syntax), apologies.

Another unrelated issue has to deal with materials, though. First, when creating a material with both surface and photon shaders, the photon shader is placed first in the material block, so mr seems to ignore the surface.

Yeah, I've been able to reproduce this. I'll try to have it fixed for tomorrow.

drexel
And, when using material SOPs to provide material changes on a group basis, a “# Per-primitive material” line is placed in the mi, but it doesn't seem to respect any material after the initial one.

I've attached an example where it seems to work for me.

drexel
Sorry for the flurry of issues,

Please keep it up (and any other readers who have issues using mentalray)

So, it looks like the problem lies in material overrides, rather than per-primitive materials; everything is fine with multiple materials, but nothing happens with the overridden parameters.