UV: how a picture gets onto a model

A texture is flat, and a model is not. Every point on the model has to know which pixel of the picture is its own. This lesson shows how that works, why textures come out blurry or stretched, and how one small picture can cover a whole field.

Why this matters

A texture on a model always works the same way. Each point on the model has an address, and the graphics card looks that address up in the picture to get a color. How the addresses are laid out decides everything: whether the texture looks crisp or blurry, even or stretched, with visible joins or without.

Settings such as Tiling or UV Scale in a material do the same arithmetic as in the first lesson, multiplying and adding numbers. They just apply it to texture addresses instead of colors. Once you understand the addresses, you stop turning those knobs blindly.

Further in the article

1. Addresses in the texture
2. Unwrapping and seams
3. Texel density
4. Tiling
5. How the graphics card reads a color from an address
6. Two kinds of textures
7. Where it breaks
8. Connections: the same idea in other fields
9. Key points
10. Test yourself