Should I put 4 UVs on one texture?

Welham14

Ok, I am wondering what the rule of thumb is for texturing some small 3D models. Let's say I have modelled four game objects. I want to use one 256x256 texture for each object. In terms of processing power in the game engine, which is Unity for this by the way, would it be cheaper to use four 256x256 textures. OR, I could put all four UV maps into each corner of a single 512x512 texture.?

Basically, is it easier for the engine if I use 4 smaller textures or one larger texture?

EarthQuake

If all 4 objects will always be seen at the same time, and all will be collapsed into the same mesh and material, its better to combine them. Draw calls will be less, which can improve performance.

If all 4 objects will always be seen at the same time, but have a different material and/or mesh for each object, it makes no difference. Draw calls will be equal.

If each object may or may not be seen in the same area/level at the same time, it is better to split them up. Texture memory will be less when less than 4 of the objects are in the scene/memory.

There are other issues too, like say if 2 of the 4 textures need to be tiling textures, combining them gets much more difficult and probably not worth the extra hassle to save a couple draw calls.

bk3d

EarthQuake hit it on the mark.

This is more of an optimization pass that you can usually do twords the end of a project. It's very hard to predict where everything will be and sometime you will end up removing some Objects. So if you combine everything at the start you will have wasted memory. If you do have a prop its best to make sure you dont have muliple materials on it unless you really really need to. You basically will double.. triple.. etc the draw calls. And if you have hundreds of those objects.. then your framerate goes bye bye.

Welham14

Thank you both for your thoughtful responses. 9 years on, I'm a blender fan now, still min/maxing my models for games!