Why our textures are unlike other games (Patreon)

By Salireths

First I need to apologize for the lack of posts last month, I was knee-deep in reworking the graphics, and there wasn't just enough exciting things to show because they weren't finished yet!

This month I'll try make up for that with a few more updates.

Textures, everyone who is even remotely familiar with games knows this word (but not always what it means), this is what is responsible for creating all the wonderful details in the virtual worlds. Whether its pretty landscapes to run around on, or a new sexy species added to the Creature Editor - they all need good textures.

Studios can just afford painting textures by hand, but because I'm the only artist here, In order to keep up with such a monstrous amount of work, I have to develop and utilize all the possible tricks and cheats.

Texturing process

Currently I'm working on a level that will be the part of the build. It is a desert oasis located in a canyon inspired by Arizona/Utah/Nevada nature, but with a prehistoric twist and lush vegetation. I drew some loose concept art of something similar a few years back.

To start working on a landscape for this environment, I need to get appropriate textures for it first. They can be done by hand, but that can easily take a month or two of work to finish a complete set, so instead I choose to use photo-scanned materials from the Quixel library that is so generously provided by Epic Games for free.

A few Quixel Materials that I selected for the environment.

Of course, if I were to just put them in like this, raw, that wouldn’t fly! Our game has a specific art-style, and having a photo-real texture would simply clash with the characters and other assets. If only there was a way to turn them into nice, stylized, hand-painted textures!

Thus I was looking and trying different ways to do automatic texture stylization, made a bunch of graphs in Substance Designer, however my initial results weren't very consistent, and it still required a lot of time for manual tweaking.

But in the end, after a lot of trial and error, having done many discoveries (which are fascinating to me personally, but I don't think I should bore you with all the details), I ended up developing a separate Unreal Engine 4 project (called it Stylizator) with a sole purpose of converting realistic textures into stylized ones! Hurray!

A special texture loaded into Stylizator.

This tool is incredibly janky, but I'm still very happy I have it now! I load in textures into the tool via the external editor and then launch the executable to screenshot the final resulting texture! The screenshot has to be 4k in resolution, and I don't even have a monitor that big. Thankfully with a bunch of workarounds I managed to make the engine render in resolution that is bigger than the screen.

Before and after Stylizator.

This blue-colored texture that I screenshotted out of the tool is there only to serve as a guide. It stores information about what the algorithm has done in order to smooth, simplify, and cartoonize an otherwise realistic photo-scan of a real surface from somewhere around the world.

Substance designer graph helping me to convert the rest of textures for the material.

The next step is to take that screenshot and put it into a special Substance Designer graph that I created, which will generate actually useful textures from other photo-scanned data from Quixel Megascans.

A bunch of textures exported: I do the same process for any other texture that I might need, and it is much quicker now with the new tools!

The result

And now, finally we have the resulting textures, which I creatively called "Surface", it is a specific, unique to our game arrangement of various textures that are actually not meant to be seen by player directly. I know it might be a bit technical, but let me introduce you to them:

Normal Map: All modern videogames have these, they create the illusion of bumpiness on surface, making it appear more detailed than it really is.

Decolored Map: It is a really washed-out color texture, I literally bleach the average color out of the photo just so I can substitute it with any other color I wish. This way, for example, I can turn the regular green grass into alien pink grass (not that I'd do such atrocity) without the need of creating more textures. It is also tiny in resolution to save memory.

Surface Map: This texture contains three different black-and-white masks in one! Red determines how shiny and reflective the surface is, Green determines how light and dark it is for further coloring, and Blue determines the displacement, how "deep" the texture is.

The Green channel of Surface map is special, it is used in tandem with a gradient to colorize the texture in any way I want. Similar technique is used in Left 4 Dead to give zombies different colored clothes, I just added a couple extra dimensions to it (literally). On top of it I add a Decoloring Map to add some hue variety to otherwise simple colors.

Two different color gradients applied to the same texture.

In-Engine

Together, when put into our special shader, all these texture maps create the end result like shown in the image below. There is a lot of complex math going on behind the scenes in-engine, but all the calculations are based from these textures in order to generate a colorful, bumpy surface that reacts to all lights, has reflections and so, so much more!

Resulting material, with two textures are doing what they should

This is without the Decolored Map, can you spot the difference?

Conclusion

Wait, we're just getting started! There is so much more to tell you about, like how are they applied to various models in-game, however I don't want to make a giant post nobody will ever read. Thus, I hope, a continuous series about new tech art updates will be more appreciated.

A sneak peek of what I will talk about in the next posts: the new UE4 water system that is used in Fortnite looks very inviting and refreshing, also check how every sand wave is an actual protruding geometry, not a flat texture - that is a tiny glimpse of the announced Unreal Engine 5 technology - unlimited polygons!

As you can see, even the artistic, a relatively less technical side of games, got enough to make your head spin. All of this had to be first figured out, planned out, programmed, and put "on rails" just for myself to follow now and in the future, because even I tend to get drowned in all the details that I just can't physically keep in my head at once.

Stay tuned for more posts about environmental art, new creatures and more updates on our journey of how we are approaching the long-awaited build.

With lots of Dragon Love,
- Salireths.