I want to have invisible objects that can be seen with a special seeing glass. The concept is similar to Legend of Zelda’s Lens of Truth. Right now I have been able to achieve this visually using a rendering side-effect of transparent glass in front of barely transparent bricks (must exceed 0.01 apparently) as seen in the picture. Basically what you’re seeing here is a hidden puzzle hint that lies beneath a 0.010001 transparency part (wooden planks). This ONLY works with glass material for some reason.
If you look at the wooden planks from a distance, you wouldn’t know anything is behind it, but if you get close enough, you can tell there is shading through the planks induced by two faces forming a corner. I have not figured out how to hide this effect even after tinkering with the CastShadow property of the parts and most of the properties in Lighting.
I tried hiding a hole in a wall, but you can clearly see it is there without a lens.
Has something like this already been done in a similar manner or via scripting? I was considering writing a script, but I’m concerned its wildly advanced and / or inefficient.