What is texture baking? A plain-English guide for 3D beginners

Texture baking in one paragraph

Texture baking is the process of calculating some property of a 3D surface (fine detail, shadowing in crevices, lighting, a procedural pattern) and writing it, pixel by pixel, into an image texture that follows the model’s UV map. After baking, the expensive source (a 10-million-polygon sculpt, a heavy shader, a light setup) is no longer needed. The image carries the result, and any engine that can read a texture can show it.

The kitchen comparison is fair: you bake a cake once, then everyone can have a slice without redoing the recipe. A renderer can sample a baked texture far faster than it could recompute the effect for every frame.

Why artists bake

• Performance. Games and the web have to draw a frame in a few milliseconds. Detail that would need millions of triangles, or lighting that would need path tracing, is baked into images instead.
• Portability. Procedural materials made of nodes in Blender or Substance do not travel between programs. A baked PNG works everywhere: Unity, Unreal, Godot, three.js, a GLB viewer.
• Editing. A baked ambient occlusion or curvature map is a great starting point for hand painting dirt in corners or wear on edges.
• Export. Formats such as glTF/GLB store materials as image textures plus a few numbers. Anything else has to be baked to images before export.

The common types of bake

1. High-poly to low-poly (normal maps)

This is the bake people usually mean in game art. You have two versions of the same object: a high-poly sculpt with every scratch and stitch, and a low-poly game mesh with a clean UV map. The baker casts rays from the low-poly surface, finds the high-poly surface nearby, and records which way it faces. The result is a normal map that makes the light catch the low-poly model as if all the sculpted detail were still there.

Blender calls this Selected to Active: the high-poly object is selected, the low-poly object is active, and rays are cast between them. A cage (a slightly inflated copy of the low-poly mesh) controls where the rays start.

2. Ambient occlusion (AO)

An AO bake works out, for every texel, how much of the surrounding sky that bit of surface can see. Crevices, seams and contact points see little, so they come out dark. The result is a greyscale map that adds soft contact shadow. Because it depends only on the shape, not on the lights, AO is one of the easiest and most useful bakes.

3. Lighting into colour (light maps and "combined" bakes)

You can also bake the full lighting of a scene, shadows and bounced light included, into a texture. Games have long done this for static scenery with light maps, and it is a common trick for mobile or web scenes where real-time shadows are too expensive. The catch: the light is now part of the picture. If you move the lamp, the baked shadows stay where they were.

4. Procedural to image

A node material (noise, gradients, masks) can be baked to plain image maps: base colour, roughness, normal. This is how a material built in Blender ends up as PNGs inside a GLB that a game engine can read.

What you need before you can bake

Every bake writes into an image through the UV map, so the target mesh needs UVs, and the UVs should not overlap (two triangles sharing one patch of image would fight over the same pixels). Blender’s manual states the same requirement: a UV map plus an image (or colour attribute) to bake into. If UVs are new to you, read UV unwrapping explained.

You also want padding (a few pixels of colour spread outward from each UV island, sometimes called margin or dilation), so that seams do not show dark lines once the texture is shrunk for distance.

Common baking problems

AI texture baking: how AI texturing is a bake

Search for "AI texture baking" and you find two ideas mixed together. One is AI tools that help with classic bakes. The other, which matters more for most people, is that AI texturing itself ends with a bake.

An image model cannot paint a UV texture directly; it paints pictures. So AI texturing renders the model from a camera, lets the AI repaint that picture, and then projects the result back onto the mesh and writes each pixel’s colour into the UV texture at the right address. That last step is a bake: camera views go in, a UV texture comes out. How projection texturing works walks through it step by step, including visibility checks and blending between views.

This is why the same baking rules apply. The model needs clean UVs (or the tool has to make them), seams need padding, and anything the AI painted into the picture, shadows included, is baked into the texture too.

What the AI 3D Texturing Studio bakes for you

In the AI 3D Texturing Studio the bakes happen in your browser, with no bake settings to learn:

• AI views into the texture. Auto texture paints 4, 6 or 8 camera views (2 credits per view) and bakes each one into the UV texture, blending where views overlap and filling small gaps and seams. Paint this view bakes one more view from any angle you turn to.
• UVs when there are none. If the file has no usable UV map (most STL and PLY files), the studio makes one first, so there is somewhere to bake. You can also choose Keep my UVs or Make new UVs when your file has its own.
• Ambient occlusion from the mesh. In box 4 PBR maps, Make PBR maps bakes an AO map from the shape itself (it checks how much of the surface is visible from 64 directions) and also makes normal, roughness and metal maps from the painted texture. It is free and runs in the browser.
• Baked-in light, reduced. The Remove lighting option in the same box evens out broad shading that the AI painted into the views. Our guide to removing baked lighting from textures explains what it can and cannot fix.

What it does not do is a classic high-poly to low-poly normal bake: the studio works on one mesh at a time, and its normal map is estimated from the painted colours, not transferred from a sculpt. For that, Blender’s Selected to Active bake is the standard free route.

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