HOW DO I CREATE GOOD UV MAPS FOR GAME ENGINES IN RIZOMUV?
Frequent question in the Rizomuv Discord
Cirstyn Bech-yagher replies
At the root of any troublefree asset and its future uses, engine imports included, lies good and clean geometry. This means getting rid of superfluous polygons – like caps on cylinders that won’t be seen or loose leftovers from asset cleanup – as well as support edges and clean loops, and as few tris and ngons as possible. Even though a game engine will triangulate your mesh, the triangulation will always be better based on clean and regular quads. It will also make UV mapping significantly faster and easier.
Once you have clean geometry it’s time to start unwrapping, and at this point many people just dive in and start cutting, welding, and unwrapping. Don’t do this. Make it a habit to consider your Texel Density (TD) first, especially if you aim to work in the industry. Many creative teams often work uniformly, with the same resolution and size constraints for their assets. This means in order to deliver your asset visually consistent with the others, you need to get used to finite spaces and constraints. At work, I see this is one of the most challenging habits for people to get into, as it sometimes requires doing the math. It’s a good habit to have, though, as utilising your (constrained) space for consistency also teaches discipline.
Considering your TD first also makes it easier to keep the concept of cut economy at the back of your mind when working. Even though UE now supports UDIMS (ish) and UE 5 seems to be able to handle huge assets, your asset will still need to run real time on various GPUS needing to calculate every cut in UV space you made. So try to keep your cuts as few as you can, whenever possible.
I often get asked about overlapping UVS at work as well, and my standard response is to avoid them at all costs unless you’re working via a trim sheet or maybe an atlas, as you want to avoid issues with baking and texturing. The same goes for stacking for game engines: unless you are very sure your bakes or textures won’t be affected by this willed overlap, go right ahead and stack them to save some space.
In the next steps, I will show you some handy space- and time-saving tweaks in Rizomuv.