Glass reflections help please

[L i am]

Hi I am trying to duplicate how reflections become distorted as fitted windows never follow the same plane in the real world. It is obvious that I will push pull the planes here and there but the flat also distorts due to compression and tension of the glass plane. I thought of using a normals map to synthesize this. Has anybody any experience in this please?

[Rich O Brien]

A Perlin Noise as bump/normal should do. Make it super big, Not a fine noise. That will shift the reflections.

[L i am]

Thanks Rich, "Perlin noise?

[Rich O Brien]

Perlin Noise is a procedural texture most render apps have. Also called clouds in PS.

At a regular scale its too detailed for glass. But if you scale it and set the bump really low it will distort your light bounces so your reflection has that real world glass effect.

Left is default Perlin scale and right is the less obnoxious variant to sell the glass.

Really small values is all you need.

[Rich O Brien]

A slighty clearer example of the effect the Perlin Noise has vs no noise...

...its subtle but the human eye expects some level of imperfection

[L i am]

Rich would you have a texture for this purpose? I have tried a lot of things but nothing works as I wish it to.

[Rich O Brien]

Procedural noises are mathematically generated. For this reason they can remain seamless as you scale but also the noise pattern will augment as you scale

TW doesn't have support for this?

Try these. But because they are bitmaps the scaling cannot augment the noise.

[L i am]

Support has been OK........but if I am doing a work getting the answer within 24 hours is a bit optomistic. Have exuasted myself finding the right normals map as they all fell below the bar for replicating how glass works in scale,

[L i am]

I tried many maps, was not convincing though. I used this one from "filter forge" worked well. It was designed for mirrors.