Tail Lights - Bump Problem

[Soljarag]

Hello,



I'm currently doing some tests for my car tail light, and



I'm using a sub object material and setting the front of the tail light glass as the color without a bump map, then the back has the color with a bump map.



However when I render it, I'm not getting any bump look at all.



If i set the entire thing to the "color with bump map" I get the effect I want.



So can anyone look at my file and see if I'm doing something wrong?


http://uploading.com/en/files/4FJDMH53/Taillight_test.zip.html




Thanks!

[Soljarag]

in the file, you can go to the material editor and find the "tail light" materal, its a Sub object material.


heres a test render with just the bump material on the back

http://img218.imageshack.us/img218/5449/taillightclearzj0.th.jpg (http://img218.imageshack.us/my.php?image=taillightclearzj0.jpg)

and heres a test render with the bump material everywhere, not using the sub object material

http://img292.imageshack.us/img292/4818/taillightbumpzu6.th.jpg (http://img292.imageshack.us/my.php?image=taillightbumpzu6.jpg)



here's the method I'm trying to use (found on another fourm) http://img341.imageshack.us/img341/3633/signalsexplanationey4.jpg

[P2sta]

hi man, can you use please attachment system for your pictures? Lights looks nice, waiting to see some renders ;)

[digitaleyes]

I will check your file later. I was planning to do same thing.

Once, I made tail light, applied meshsmooth, than edit poly and I selected all polygons behind and extruded them (by poly) for small amount and than again mash smooth. Therefore, I modeled bumps... However, with glass material it was rendered much longer than rest of the car. :D

[Soljarag]

Hey,

Yeah, I have come to the conclusion it will just be easier to model the bumps.

Just FYI, I found out why the Sub Object material was messing up. Vray considered the front and back faces different material, therefore rays would go in one face and wouldn't have another face of the same material to exit (or something like that... I was talking to someone in a vray chatroom about it)

So he sugested Unwraping the object and painting the bump map patteren on just the faces that needed it. Vray then would see the object as one material and the rays would have somewhere to enter and exit.

So I tried that, however since I modeled the entire thing in Rhino I was having trouble Unwraping it..... when I converted it to polys I got alot of 5+ sided polys that made it impossable to get a good, even Unwrap (so if anyone is modeling their car with polys this trick should work just fine)

[digitaleyes]

What about multiple glasses... one regular, and one thin, bumped, behind this regular?