how to determine what size texture map to use

hansedr

Hello everyone. I have a question that I haven't really found the answer to via google & such. How do you determine what size texture map to use when creating a poly mesh for something such as a mobile game or PSP spec system. For example, if i create a grid that is 8x8 (1 grid box = 1 meter) that would represent a street & sidewalk, would that mean a total texture size of 64x64? Any help would be great. Tks

Quasar

well if you're making a texture for a game, there are two main factors that will determine your texture size. The first is how big the object will be on screen and the second is your memory budget. Ideally you want the texels (pixels on the model itself) to be about the same size as your screen pixels, but of course we don't live in a perfect world, so you just have to get it as close as possible.

Bruno Afonseca

It's up to you, actually. 1 meter for a game like micro machines is one thing, 1 meter for sim city is another. Depends on how far things are from the camera and other things. For a handheld 1st person shooter where you see the walls from very close up, I'd make each meter be 128 pixels for example. Maybe even 256.

greevar

You might want to think about how populated the screen will be for the majority of the game or level. If it's going to be dense, keep your textures and poly count low. If it will be more sparse, then it might benefit you to add more detail to what you have in there.

keres

Be safe and create all of your textures at a "high" resolution of at least 512px at the start. If you need to scale them down, you can. Otherwise, you're just dandy. Most games don't use tileable textures above that. Model textures, however, are typically much higher. These games are now seeming to use 2048px maps for first person hands and whatnot.

hansedr

wow, thanks for all the info everyone. I guess I just want to make sure that I try to keep everything uniform so something doesn't get to much or little detail of a texture map. Also, and i guess this could go either way based, i have read some people choose to create large texture maps & scale down however it creates artifacts & distortion as opposed to working with the actual texture/pixel size.

CheeseOnToast

The lower the final resolution, the more you should be working at actual size. Reducing a 128x128 texture to 64x64 will cause a lot of blurring and loss of detail. Going from a 2048x2048 to a 1024x1024 will be far less noticable. Personally, I almost always work at true res as you can use one pixel lines etc. knowing that they're not going to be blurred into oblivion later on.

Mark Dygert

I normally work off of a 4:1 ratio, 4 pixels to every game unit. With 4:1 if you have a plane that is 32x32 then your texture sheet would be 128x128.

I helped a guy unwrap a crate once: http://www.polycount.com/forum/showthread.php?t=77405
I also helped a guy figure out how to unwrap a more complex object: http://www.polycount.com/forum/showthread.php?p=1225409#post1225409

Unless you're view and screen resolution is locked like a top down 3/4 view like a strategy game its hard to guess how big your pixel will be on the screen. When the player is the camera its hard to try and guess how close they will or won't get to your object. So rather than have inconsistent textel densities I shoot for the same ratio on all the objects.

I try to paint at res, however I keep in mind that one of the first things to get cut down is the material sizes. One of those brilliant fixes for being over the tech budget, whack all the materials for everything in half! Or things might get mip mapped prematurely depending on what else is on screen. Whatever happens it's probably a good idea to re-size your materials and see how they look at smaller sizes while you're working on them, make adjustments and account for things that might not hold up as well when then get downsized later.

keres

Soon we will use voxel meshes instead of textures, and we won't have to comment on the 4:1 voxel-to-screen-pixel ratios! Oh, how I can't wait.

misfit2588

My question is do you choose your textures size based on what type of game you are making? 

If i was making a FPS i would have to use 2048x2048 because the player is going to see much more of the level, correct?

Bruno Afonseca

Base your texture size on the texel density and size of your surfaces. First determine how many pixels/m you'll want by testing, allocating your memory budget etc.

For example, Rainbow Six Siege uses 1024 texels per meter, so a 2048x2048 texture would cover 2x2 meters. Some materials allow more repetition without creating patterns that are too noticeable, so you could use for example a 512x512 for 0.5x0.5m and tile it. Other games have different texel densities.