Advice on creating transparent surfaces / glass
polycounter lvl 3
Hello,
I'm creating a modular weapon build that features an optic with glass and I don't know how I should start.
I've created a normal map that I'm satisfied with and am moving onto creating an occlusion map, but I don't know what I should do. I've created PBR textures before, but I've never made transparent materials and I don't know where I should start. Should I even have any occlusion on a transparent material? Also, how should I create the actual dot that is used for aiming?
Some guidance would be greatly appreciated.
Thank you 😊
Replies
Totally depends on the game engine. Where are you rendering this model?
Also depends on the use in-game. If this is a first-person weapon, the sight is not what you look through when you are in "zoom" viewing mode; instead that's a different specific HUD, usually all 2D.
I'm just creating a game-ready model for practice and for my portfolio, I have no intention of using it in an engine. That being said, I didn't know that was something I had to consider. It would be used as a first-person weapon. I'm planning on rendering it in Marmoset Toolbag 3, just as I baked it.
Ah Toolbag. Then I'd recommend checking out @EarthQuake 's assets and tutorials.
https://earthquake.artstation.com/projects/kl0A6
I would make a separate texture for the glass and set that to refractive (Transmission: Refraction in TB4). If using raster rendering, make sure both lenses are separate objects so they sort correctly when looking down the scope.
I would give it some subtle variation with some light scratches and such in the roughness/gloss map. Maybe a fingerprint as well somewhere. A little bit of dirt around the edges perhaps, you can do this in the gloss and albedo and then make a refraction mask to blend between the clean see-through section and the dirty sections.
For the red dot, you can do that with an emissive map. Make the texture black except for the dot.
Sounds great. Separate texture but I can still use the same UV tile, correct? And will I need to add extra geometry for the red dot in the middle of the optic, like a flat transparent plane?
Could be in the same UV tile, just as a different material yeah. If you want the "holographic" effect, then yes a floating piece of geo with emissive on it will do the trick
You could do the same uv set/same texture or a different one. I would tend to do a dedicated uv set/texture for transparent objects. You can make it smaller and you'll probably want dedicated maps (like a refraction mask/alpha mask) that you don't need for the majority of the rest of the asset, so it can be more efficient to do it this way. But it's up to you.
You don't need an additional mesh for the red dot - you can make it part of the lens texture - unless you're doing a more complicated effect.