vrayHairMtl : Not respecting light include/exclude

[RE:FORM_STUDIOS]

Hi there, I hope someone can help.
We're coming close to the end of a big production and a strange issue has appeared with a scene with hairfarm/vrayhairmtl.

It appears that if I add the hair object to my vrayLight (dome) exclude from shadow and lighting, that the hair material is still being shaded as though no exclude is applied.

Is this a bug or a known limitation of the hairmtl?

Vray 2.3.01, max 2013.

Any help appreciated!

[vlado]

The problem is that the hair object is generated at the start of the render, and this temporary object is not present in the light's include/exclude list. Will have to think of some way to solve this.

Best regards,
Vlado

[MattClark]

Just wanted to bring this up again, as it's cropped up on another job here.

Using Hairfarm, with Max 2015. If you add a hairfarm object to an include or exclude on a light, then it seems to do the opposite of what is expected.

If I exclude the hairobject from the a light it illuminates, and if I include it does not. Interestingly if you have the emitter object visible in addition to the hair, then you can see that the emitter responds correctly to the exclude/include state, and the hair always does the opposite.

Feels like a bug...?

[Svetlozar Draganov]

Thank you very much for the feedback.
We've run a few quick tests here but we couldn't reproduce this issue.
Would it be possible to prepare a sample scene for us along a screen-shot of the result you got in your environment and send for investigation.

Let us also know the exact V-Ray and HairFarm version/build.

[MattClark]

Sure, here you go:

There is a vray light directly above the sphere. I'd expect the hair to inherit the include/exclude from it's base geometry, the sphere.

In this first image the sphere is set to exlude both illumination and shadow casting:



You can see that the sphere itself does not illuminate or cast a shadow, but the hair does.

In this second image the sphere is set to include both illumination and shadows:





As you can see now the sphere is the only thing lit, but the hair is now not lit.

hairfarm 2.4.3 (build 166)
Vray 3.10.03
File here: https://drive.google.com/file/d/0BxV...ew?usp=sharing


Thanks

[Moriah]

Upping this. Is there any fix coming? I've asked the hairfarm guy and he said that without vray there isn't any problem.

My workaround for this is to have lights specifically just for hair, unhide everything, select the inverse of all the hairs, and add the selection set as exclude on the hair lights. Same for creating mattes for hairfarm. With ornatrix i have no issues, but with hairfarm i have double the work, specially when having to AO/matte/light etc. hair.

3dsmax 2015 sp3, vray 3.2 and hairfarm 2.4.5 (build 168 )

[yavor.rubenov]

Hello,

We managed to fix this issue but it didn't make it for the 3.2 release. I think the fix is in 3.20.02 but I'm not sure - will check on Monday and write back.

Best regards,
Yavor

[Moriah]

We have 3.20.02 here and it doesn't work still. If you have any updates let me know. Thank you!

[yavor.rubenov]

You are right - now that I've checked - the fix is not part of 3.20.02.

Best regards,
Yavor

[vlado]

Will try to include it for 3.20.03

Best regards,
Vlado

[Moriah]

I tried today's nightly and it works! Thanks

[werticus]

Does this also fix the vrhair not respecting the vrtoon environmental effect exclusion? Because if not there is another bug for you

[yavor.rubenov]

We fixed the toon exclusion lists when we added layers there - so it should work

Best Regards,
Yavor