Texture And Material

[LLS]

How do I create a glossy_map?

[Sven]

Well that completely depends on the software you wanna use and what maps you create along with it or you already have.

First take a look at the gloss map section here: https://supertuxkart.net/Materials
It broadly outlines how the different color channels work and what they do.

I create all my textures in substance designer, so I can create a gloss map easily alongside the albedo map, that's the easiest and most accurate way to do it.

But I assume you are more interest in either creating them from an albedo map or from existing black and white maps.

If cou download a pbr material from almost any website today it will come with all the needed maps already.
You want to look for roughness, metalness and maybe emit.
You will always find a roughness map as it's esential for all materials. If it's a metal material you'll also have a metallness map. And very rarely you'll also have a emit map.

Now I do the next steps in GIMP but you can use any software you like.

First open the albedo file in GIMP (we won't need it but it automatically has the right resolution and ensures that the image file is in rgb and not just black and white as it can be the case with the roughness maps).

Now add all the relveant maps to gimp roughness, metallness, emit.

You can get rid of the albedo map löayer now.

Add a layer and fill it completely black at the bottom of the layerr stack.

Roughness map: invert the roughness map, then go into the color channel settings (to the right side next to the layers) and deactivate the red channel.
   
Now fill the layer comlpetely black. This should lead to an image that is only black and red.
In theory your done with the roughness map now, but STK treats them a bit different than other 3D software. Genrally you want to darken your roughness map by about 50% (unless you want something mirror like) to get desired results. Make sure to activate the red channel again before darken the image.
   

For the metallness map you just do the same as above but without inverting the image first and with the green instead of the red channel.
The metallness map usually also needs to be made a bit darker but it depends more on what look you want.

And for the emit map it's the same just with the blue channel.

After all maps are done, set the blend mode of each (exepct the bottom black layer) to add and you should have a perfect glossy map.



If you only have the albedo texture you'll first have to create the needed maps yourself, that can be done by modifying the existing albedo map. Then do the steps above to layer them together.