Texel Density – What Is It And Why Is It So Important?

Texel density refers to the texture resolution on an object in comparison to the real-world size of the object. It is usually measured as pixels/meters or pixels/cm. For example 512px/m. What this means is that for every meter in the game there will be 512 pixels on that texture. If you have a 1x1m wall the texture would have a resolution of 512×512, if the wall was 2x2m then the texture would need to be 1024×1024 so that each meter squared has a resolution of 512×512.

Maintaining a consistent texel density might seem like an unimportant technical detail in the grand scheme of making art, but it is essential for not only creating a great-looking asset but for keeping the quality of art consistent throughout the entire game. Having objects with wildly different texel densities sitting next to each other shines a light on quality issues of the assets and can be emersion-breaking as the player is no longer looking at a consistent world.

It also works as a great way to ensure that the textures are roughly the size they should be, which stops artists from generating something that’s too low quality or using textures that are too big and as such are a drain on performance. It’s easy for an artist to just look at the size of the object they are texturing and work out how big the texture needs to be, there are also tools to do this which is helpful for more complicated assets. This helps take the guesswork out of texturing.

As computing power increases and with it the quality of graphics the texel density increases as well. For the Playstation 5 / Xbox Series X generation, a good rule of thumb is to have 512 px/m for most things, sometimes upping it to 1024 px/m for things very close up to the camera such as first-person shooter weapons. This will most likely increase in a few years as it has done previously.

These numbers are only a guideline. If you have to view a lot of things up close you and you generally don’t have too much on screen, then it might be wise to increase it to 1024 px/m for most stuff and 2048 px/m for very close objects. Just be aware that changing the texel density for an entire project will have a huge impact on performance, so it’s best to work out early what you want to go with.

There are two ways of increasing the texel density. Making the object smaller or increasing the size of the texture. Most of the time you will be unable to scale the object, as it will be built to the correct scale, but if it’s something like a rock that has been scaled in the game engine, consider not scaling it as big and see if you can achieve the same thing with multiple smaller objects.

The usual way will be to increase the size of the textures you are putting on the model. The downside to this is that you will only be able to make quite big changes to the texture sizes, to ensure it remains a power of 2. It will also have a bigger impact on performance, so you will have to carefully choose which ones are worth increasing.

A final thing you can do to improve the texel density, in some cases, is to check how the UVs have been unwrapped. If you only need a fairly small increase in texel density you might be able to unwrap the model in a more efficient way to get a slightly higher density by using more of the UV space.

New to texturing? Check out our Guide To Textures And Materials.