Secondary Ray Bias workflow?

[dean_dmoo]

Hi,

I'm working on a model at the moment which has a lot of duplicate faces and resulting black render surfaces. Yesterday I started cleaning it up manually but it's a huge appartment complex so I would rather not waste my time doing it manually. I found a script that might hopefully help (DDF) and will try it later today. *fingers crossed*

However I read that changing the secondary ray bias from 0.000 to 0.01 or similar could help in this case aswell. However I would like to know what negative effects this would give for the renders if it does help cleaning up the balck surfaces? (They're all archviz stills).

Can anyone tell me? Thanks.

Dean

[super gnu]

i would not hope for much from any automated script solution.

when i have a real messy model and no way to get a decent one, i usually just make sure "double sided" is turned on and "reflect on backside" in all materials.. then crank up the secondary ray bias untill the problem improves enough to photoshop the rest.

i once accidentally set ray bias to 11.. very odd. caused render to look really wierd, with shadows offset a very long way from objects etc.. basically turn it up as high as you can to clean as much crap as possible, but check for shadow wierdness creeping in.

[dean_dmoo]

Thanks, will keep an eye out. I'll see how far I can get with manual and hopefully the script and then see the ray bias settings for any final issues.

[glorybound]

Have you tried the forensic script?

[dean_dmoo]

Nope, never heard of it. Do you have a link?

Thanks!

Found it:
https://www.sinisoftware.com/products/plugins/forensic

[^Lele^]

Hi,

I'm working on a model at the moment which has a lot of duplicate faces and resulting black render surfaces. Yesterday I started cleaning it up manually but it's a huge appartment complex so I would rather not waste my time doing it manually. I found a script that might hopefully help (DDF) and will try it later today. *fingers crossed*

However I read that changing the secondary ray bias from 0.000 to 0.01 or similar could help in this case aswell. However I would like to know what negative effects this would give for the renders if it does help cleaning up the balck surfaces? (They're all archviz stills).

Can anyone tell me? Thanks.

Dean

0.001 is normally what's used.
cfr:
https://docs.chaosgroup.com/display/...lobal+Switches

and

https://docs.chaosgroup.com/display/...condaryRayBias

[anthonyh]

I don`t count on 2nd ray bias as a total solution unless every poly is the same distance overlap, I find if there`s discrepancies as one surface is fixed another can end up rendering `scratchy`(not sure what the coplanar black intersect look is called). CAD can be pretty bad for this issue just to find a sweet spot, this goes double if you`re doing any kind of x-ray/toon line look. Scriptspot probably has a duplicate face finder script somewhere surely ? You might also consider using a position randomiser script, if you`re very conservative with the position it might move coplanar objects away from each other just enough to help, might need to increase you`re 3dsmax spinner accuracy first.

[dean_dmoo]

Thanks for the responses.

Tried the script i mentioned but that didn't do anything. Ended up increasing the ray bias to 0.01 or something like that and that fixed the issues.