Double faces cause problems with VrayDirt and alphas

[Mr.Hoo]

Hey there,

I have a small test scene attached.

Five spheres, two of them are on the same position (causing double faces), the ones on the very right side of the image.

A layer material override is given (vray dirt connected to a light material).
All spheres were given a primary visibility=off.

In the rendered result you can see the errors, which are caused by the alpha.
There is a kind of a mess going on.

The second images shows a similar problem, same setup, only default vray material and one directional light coming straight from above, with raytraced shadows on.
There's the same error again.
You can see the hidden sphere as a messed-up result at the very right of the image....


In our projects (with really high detailed models) you often cannot avoid having doubled faces in it or cleaning it up would take days...

Is there any workaround or any feature to get it handled?


Regards

Dominik

[Mr.Hoo]

***SOLVED**

its the secondary rays bias, thanks Oli (ultrasonic) for the pointer!!

take it to a value of say: 0.001 and all the errors are gone!

THX

Dominik

[ultrasonic]

its the secondary rays bias, thanks Oli (ultrasonic) for the pointer!!
Dominik

You're welcome my friend

[ALFRED_ST_MEDIA]

ok, that may have worked for Dominik, but not so for me.

I have vray mesh proxies that have LOD turned off, and low rez geo with all render attr's turned off, so you see the cruddy geo int he viewport, and the lovely vrmesh in the render. All is good with all passes EXCEPT the vrayRE_Extra_Tex vrayDirt pass. here I get all sorts of ugly, as you can see bellow. I have gotten around this by a pre-render mel script that hides all the low rez geo, but I would love to see if there is a fix for this. Changing the 2ndary ray bias didn't do anything...well...good for this instance.

[vlado]

Did you enable the "Work with transparency" option for VRayDirt?

Best regards,
Vlado

[ALFRED_ST_MEDIA]

Vlad,

works perfectly. Thank you.

-ctj