pbr glass problem
18878 20 3- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
I'm trying to (perhaps foolishly) use the shipped glass material in a pbr render, and I'm getting black artifacts whenever I set the refractive IOR to anything but 1. The closer I set it to 1, the less black I get. I've tried surrounding the entire scene with a white cube so that there is no possibility of the refractive material ray not hitting legitimate geometry, and I still get the same result. I'd like not to start from scratch and write my own glass shader, but that's what I'm looking at now. Surely the shipped glass shader still isn't broken, and I've just missed something really simple?
9.5.142
9.5.142
- anamous
- Member
- 186 posts
- Joined: Jan. 2006
- Offline
- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
- andrewc
- Member
- 1002 posts
- Joined: July 2005
- Offline
- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
After doing some poking around, it looks like at least part of my problem is that the Trace Vop in the vopnet that contributes the refraction contribution isn't taking into account either the reflection map or the background colour when geometry isn't hit by a ray. In a traditional micropolygon render this works fine. Can you confirm?
- andrewc
- Member
- 1002 posts
- Joined: July 2005
- Offline
- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
That being the case, how best is it to completely surround my geometry with a dummy environment for the refraction rays to find while still being able to use the envlight (if I surround my geometry with an environment, light is no longer cast from the envlight because of the shadow cast onto the scene by the dummy environment - the shadow mask input field doesn't seem to have any affect in a pbr render).
- anamous
- Member
- 186 posts
- Joined: Jan. 2006
- Offline
- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
That doesn't solve the problem - I can't use the glass shader in a pbr render unless the environment is completely contained (rays that don't strike geometry will return a black result), and if the environment is completely contained, I can't use the envlight because whatever geometry that I've used to contain the environment eliminates the envlight's contribution.
I'm determined to get this to work with the tools at hand - I'm still convinced that I must be missing something simple. Certainly it's not impossible to use the glass shader and the envlight together in a pbr render. Right?
I'm determined to get this to work with the tools at hand - I'm still convinced that I must be missing something simple. Certainly it's not impossible to use the glass shader and the envlight together in a pbr render. Right?
- eetu
- Member
- 606 posts
- Joined: May 2007
- Offline
- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
- eetu
- Member
- 606 posts
- Joined: May 2007
- Offline
- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
- eetu
- Member
- 606 posts
- Joined: May 2007
- Offline
- anamous
- Member
- 186 posts
- Joined: Jan. 2006
- Offline
- Simon
- Member
- 2199 posts
- Joined: July 2005
- Online
- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
- lynbo
- Member
- 47 posts
- Joined: July 2005
- Offline
- moonlightkiss
- Member
- 156 posts
- Joined: July 2005
- Offline
- stu
- Member
- 246 posts
- Joined: July 2005
- Offline
-
- Quick Links