For this weeks check in for CAGD 373, I’ll show how I’m doing detail masks while texturing. In video games it can be useful to create textures that are flexible, and can be re-colored as needed. However, we don’t want to recolor everything in our texture, and we want some things to remain consistent. For my first part of this project, I’m doing some decorative pieces, like barrels, and figured this would be the perfect opportunity to show how I do detail.
The end goal is to make a texture that only adds color to some areas, but is transparent in the rest, so we can recolor the object in a the game engine. To do this, you need to first let substance fill in transparency. To do this, just click the + arrow and add an Opacity Map.
After you’ve done this, you still won’t see transparency. You’ll also need to swap your shader over to “pbr-metal-rough-with-alpha-blending” or “pbr-metal-rough-with-alpha-test”. I tend to get better results with the 2nd.
Once you have these set, you should be able to use the Opacity channel on your layers. I normally add a fill layer, and then set it to max opacity. Afterwards I build everything on top. My end product should have all of the “detail” but with no opacity or color, looking something like this:
As you can see, We have the dirt, dust, and metal details that we want, but the rest is transparent. The metal and roughness values, as well as all our other maps will still export out fine even though we can’t see them, just the base color underneath is not visible, so nothing is currently rendered.
After exporting to substance, I build my texture.
Instead of putting our Albedo map on Albedo channel like normal, I isntead placed it on the Secondary “Detail Albedo” map. This means that the Albedo map we made in substance overlays the primary one, so we can make the base color anything we want.
Even after coloring the base material yellow, the brown of the dirt still shines through. This method is a easy way to add a lot of extra variation to your objects without a huge increase in work.
While this method is not currently perfect, with the base color that we shift over shining through just a bit, it still helps you better visualize for this type of work flow. I’m sure that with some substance designer built shaders it would be trivial to have to proper channels, but for now I am fine with what I’ve got.