Anisotropic refraction
Blender supports anisotropic reflections, but is locked to isometric BSDFs for transmission.
With anisotropic BSDF for transmission, you can easily create swirly scratches and other highly realistic scratches through windows, windshields, plexiglass, aquariums, etc.:
There are also a few other niche effects that can be achieved with this, like the effect of lights stretching in car windshields:
Normal maps are a commonly suggested alternative for scratches in refraction, but here's a comparison between true anisotropic transmission and my best attempt at using a normal map of the same resolution. It's not really even close:
Just for reference, my examples were actually rendered in Blender/Cycles, but using a fork of Blender
5 Comments
Nice renders . I see that your the developer of that branch. Have you considered to creatie a pull request. So we can check how to include this in an official release?
It was an almost entirely vibe coded proof of concept to be able to demonstrate the use case. I'd be very self-conscious about throwing AI generated code (that I'm not able to review) at the real developers of an open source project.
Let me know if you still want a pull request given that caveat, and I'll clean it up and see what I can do.
As long as you take ownership (clean up and address the feedback) it should be fine. We are not against using AI as a tool, just don't use it as a solution.
Even if this is vibe-coded, just sharing the code you got for any developpers to put hands on this, take the code and make it good is already a good move. I'd love to see that in fully merged Blender at some point. Just sharing a PR is the start of at least probably getting the interest of the community developpers.
I won't be able to do either. I cannot stress enough that I'm not a developer, I can't meaningfully review the code or take any ownership of it. My entire contribution to the Anisotropic Refraction fork consisted of knowing what I wanted and having a subscription to Codex.