Reply To: My First Game: How many UV layouts should I create?

There are many different ways you can approach textures for assets based on different criteria.  Not sure what kind of art style you’re going for or what assets you need, but there are some different techniques you can look into and see if that works with what you’re trying to achieve:

• polycount wiki has plenty of game dev techniques. Highly suggest going through and reading up if you’re not familiar with the website.
• MultiSubObject Materials are great if you have a lot of meshes that use procedural materials; can save texture space this way by just having 1 texture set, say, for a brick material, but that texture can be used across a lot of “building” assets without each having their own brick texture set. This also allows you to create “material slots” that you can then plug in procedural/tiling textures. I hope that makes sense. I can pull up a more visual example if needed.
• An amazing post about how Star Citizen gets such crisp detail on their ships without using crazy high texture sizes.
• Another thing to add to your arsenal is using detail maps (this is the name I use for this particular map, it may be called something else), which can save texture size, as well.  What I mean by that is your greyscale maps (so Roughness, Metalness, AO as the standard, but any greyscale texture can be stuck in a detail map) can be stored in the RGB channels of a texture, so instead of 3 separate 24 bit textures, you have one 24 bit texture with 3 maps in it.  Then you plug in the corresponding channel for what you’re looking for.  Each channel has varying degrees of “detail afforded,” so if you need something with the best detail, stick it in the Green channel, then Red, then Blue is the worst.  I hope that makes sense.  So, using this technique, you have three 24 bit maps per asset instead of five 24 bit textures.
• You can combine varying sizes of maps if you need to.  For example, you have your textures, but only 1 has some small detail, like an emissive map.  If it’s only a BW texture, you can totally scale that down to something as small as 128 if you want to.  There should be minimal loss of visual impact, but this is something to experiment with.  Or heck, you don’t have to resize it; you can chuck it into the DET map in the Alpha channel, increasing that map by only 8 bits.  Make sure to save it with alpha.
• Vertex painting/colors is also something to look into. You can totally use a DET map with BW textures other than Roughness, Metalness, AO, such as some sort of grime texture instead in each channel to drive how the vertex painting is masked out. It can save on mesh density while still providing visual density.

There are definite costs associated with each technique here and as yet to be discovered, so it’s about balancing each cost against if you need it or not.  Why spend the resources on something the player will never get up close and personal to when those resources can be used to make something the player will see really, really good?

I hope this is a good starting point for you.  Good luck!