Glass wont Affect shadows correctly in a Mutli-sub objects

[david.jones]

Hi, i have only really been using vray recently.

 

Previously, when i've created windows etc, i have always usually created the entire window, including glass, as a single object, and used multi mat's for glass frame etc.

 

But doing this with vray i get a problem, glass loses its ability to affect the opacity of the shadows, once it is in a multi material.

 

I've tried loads of ways to get round this, but i am stumped, anyone else found this to be a problem?

 

I guess it now just means a different way of working in future, but it's going to be a big pain in the arse to open all my previous models and detach all glass to a seperate object, when anything from my library is used.

[martin walker]

David

 

dont know whats happening there, I use Multi Sub Materials 100% of the time, and never had this problem.

[david.jones]

Really?? Thanks for the quick reply martin.

 

Ok, incase this was due to a corrupt file or material, i created a new scene, new materials, one 100% opaque, one 50% and one 0%.

 

Created two boxes, one has those mats as a multisub, and the other has been detached to 3 seperate objects, with the same mats as individual, not multisub.

 

And, there we go, the multi sub versions dont cast shadows properly. I really cant think what i'm doing wrong.

[martin walker]

strange, ive attached a recent image ive done with the multi sub material assigned, as u can see its OK

 

do you want to send your test scene to me and I'll try on my PC ?

 

pixel_ninja@hotmail.com

 

Im using Max8 and V-Ray 1.5

[pg1]

I read something about this on chaosgroup there is a known bug with vray RC 3

 

This solution was posted by lukx

 

My fix for

 

"Known issues:

(*) "Affect shadows" and "Affect alpha" options do not work for VRayMtl's inside a Multi/subobject material. This will be fixed as soon as possible"

 

Lukx is coming with help

 

If you still need to use for example glass in mulisub material first create vray blend material and as base material put this your material in which you need to use affect shadows. That's it Affect shadows will work. I didn't check affect alpha cause I never use it.

 

Here is the link to the post on chaosgroup

 

http://www.chaosgroup.com/forum/phpBB2/viewtopic.php?t=17187

 

I haven't tried it but Vlado gave it the thumbs up so it should work

 

Hope it helps

pg1

[david.jones]

Thanks alot pg1.

 

Yep, that works a treat.

 

Weird though, because martin redered my test scene fine without changing anything, must be i'm missing a patch or something.