Texturing car tail lights

Ricky K.

I always had a problem(couldn't figure out) texturing cars tail lights, as different cars have different tail light textures. 

What I mean with tail lights is the exterior glass cover because headlight glass is just a transparent glass while tail light glass are different.Please guide me with the procedure to do so (preferably in 3dsmax, Photoshop, Quixel Suite pipeline).

jaker3278

The rear tail lights let the light through from the back and glow red, you could make the texture you apply to them a transparency, quixel suit supports transparency in the additional maps you can choose. Which you can then use in marmoset and light from the back of the transparent red texture and it should glow, you could also just have the red tail light texture glow its self with self illumination. 

I  think you should try to make them in 3dsmax as though they would be on the car, and them test out the different methods. 

Eric Chadwick

If for a high-end racing game, I would suggest authoring an emissive texture for the interior, and add a transparent cover just for realtime reflections.

For the interior of the light, decide which make/model car, then search for replacement parts. Should give you lots of good ref. Notice how there are shiny angled mirrors inside. So, model it and bake to a normal map. 

Ricky K.

Thanks to both of you. Its going to take a while trying the steps given by both of you.
I'll give feedback here after getting close to the results.

Obscura

For non-high-end result, something more generic, you could have an opaque material for the glass and a single layer of parallax with emissive for the lamp distorted by the normals of the glass. This normal also wouldn't be plugged in directly as a normal map, so you could have the smooth outside but distorted inside. This works nicely if you don't want to be able to break the glass. 

Obscura

That would look something like this:


This is done using the above mentioned method - bump offset node in unreal / parallax, and opaque material. Note how the reflection of the light source stays smooth because the normal isnt directly applied to the material. If you are working with unreal by any chance, you could also use the clear coat shader that would allow you to have separated specular for the interior of this with the parallax applied , as well.

My 5 minutes textures were looking like this:



So depending on what you are going for, something like this might be a cheaper solution. Transparency with reflections and real time lighting isn't the cheapest thing to render, but it can be required  based on your goal.

Prime8

Thanks for the info, I just found this post before working on my first head lights as well (though this post is for tail lights
Hope OP doesn't mind if I place some questions here as well.

Eric Chadwick said:

If for a high-end racing game, I would suggest authoring an emissive texture for the interior, and add a transparent cover just for realtime reflections.

For the interior of the light, decide which make/model car, then search for replacement parts. Should give you lots of good ref. Notice how there are shiny angled mirrors inside. So, model it and bake to a normal map. 

I used this method and it looks quite good already, but I would like to have a normal map on the inside of the glass to catch a bit of light, like in Obscura's example, similar to older car lights.
The normal on the backside is ignored however and if I put it on the outside it doesn't seem to catch much light.
In total the glass looks to transparent now, I can adjust the alpha but that results only in a more milky glass.

Using Marmoset Toolbag 3

Obscura

To solve this, I would use double sided geometry. But not through a material. I would duplicate the geometry manually flip out the normals, and move it somewhere else on the uvmap where it can have its own flat normals. Or give it an another material without the normal map applied.  You can also give it a little bit of roughness to have bigger / more blurry highlights in the reflections. 

EarthQuake

Try the refraction shader rather than additive, that should give you better results.

Tutorial on how it works here (ep7): https://www.marmoset.co/posts/getting-to-know-toolbag-3/

Prime8

Thank you Obscura and Earthquake!
I modified the template glass which used addition, should have looked at your tutorials right from the start.
Will share the result here later.

Prime8

Needs a bit of tweaking but getting close now. Using on flat and one normal mapped glass with the refraction shader.