Texture Baking in Blender Cycles: A Step-by-Step Guide for Architectural Models

What you'll learn in this guide

Texture baking in Blender Cycles transfers selected surface information to an image or color attribute. It can be used to prepare Base Color or normal maps for game engines, convert Ambient Occlusion or procedural textures into images, and create lightmaps. In architectural visualization, it can also be part of a workflow for reusable assets and scene-specific surface data.

This guide covers when to bake, the required mesh and target settings, how to choose the right bake type, and how to reduce UV seam issues in the result. It also explains the basics of transferring details from a high-poly model to a low-poly one.

Requirements: mesh, UVs, and a bake target

Before you begin, make sure the object you plan to use is a mesh and has a UV map. You also need to prepare a target for the baked data: the source identifies this as either an Image Texture node containing an image or a Color Attribute. To bake to an image in a material, the relevant Image Texture node must be active and selected. If no suitable target is active, no image will be baked for that material.

Choose a bake type based on the data you need. For example, Ambient Occlusion bakes ambient occlusion and ignores scene lights. The Shadow type bakes shadow and lighting information. Options such as Normal, Roughness, Emit, and Diffuse target different surface or material passes, as their names suggest. Combined brings together material, texture, and lighting data, excluding specularity; the components included in this pass can also be toggled individually.

During baking, Cycles uses the sampling and bounce values in the render settings. The quality of the bake is therefore not independent of the render settings used for the scene. Before you start, check that the current settings are suitable for the intended output.

Step-by-step baking workflow

1. Define the intended use. Exporting only surface color or normal data is not the same as baking scene lighting into a map. Identify the need—such as exporting to a game engine, creating an AO map, or making a lightmap—and choose the bake type accordingly.

2. Check the mesh’s UV map. The surface to be baked needs UV coordinates. How the map uses the texture space determines where data is written in the image. For architectural models, Box projection on an Image Texture node can also be a practical option: the image is projected onto the sides of a box according to the axis closest to the surface normals. However, this projection does not replace the UV map required for baking; make sure the UV requirement is met separately as part of your baking setup.

3. Set the output target. To bake to an image, make the Image Texture node containing the image active and selected in the material. Alternatively, use the active Color Attribute layer on the active mesh. The target is associated with the Target setting in the Output section. Don’t start baking without checking the target.

4. Choose the appropriate Bake Type. Use Ambient Occlusion for AO and Shadow for lighting and shadow data. Combined combines material, texture, and lighting components, excluding specularity. For more specific needs, consider Normal, Position, UV, Roughness, Emit, Environment, Diffuse, Glossy, or Transmission. If you’re baking Normal or Displacement with a Multiresolution Modifier, Bake from Multires uses the difference between the low- and high-resolution levels.

5. Set up high-to-low-poly transfer if needed. Selected to Active bakes the surface shading of selected objects onto the active object. Rays are cast from the low-poly object toward the high-poly object. If the high-poly model does not fully enclose the low-poly model, use Max Ray Distance or Cage to control how far the rays reach. You can use an automatically generated cage or specify a separate Cage Object. If you create your own cage, the topology of the two meshes—the number and order of their faces—must match.

6. Set the margin and bake. When baking to an image, a margin is created around UV islands by default. This margin is intended to reduce artifacts at UV seams during texture filtering and mipmapping. The Extend method extends boundary pixels outward; Adjacent Faces uses pixels from neighboring faces along the seam. Choose the method and size in pixels, then run the bake with the current settings from Render > Bake.

Common mistakes

One of the most common issues is failing to get an image output because the bake target is not active. Make sure the Image Texture node containing the image is both active and selected in the correct material. If you’re baking to a color attribute, check that the active mesh and active Color Attribute layer are appropriate.

Starting with a mesh that has no UV map is also an inadequate preparation. Box projection can be useful for architectural models, but it does not remove the UV requirement for baking. The selected bake type may also fail to produce the expected data: for example, Ambient Occlusion ignores lights; according to the source, use Shadow to bake scene lighting and shadows.

During high-to-low-poly baking, if the ray distance is too short, some parts of the high-poly object may not reach the target. If you’re using a cage, check the geometry correspondence and how the cage relates to the target surface. If you see gaps or seams around UV islands in the image, review the margin method and size.

Memory use also needs to be considered, especially when working with many high-poly source objects. According to the Blender documentation, each object used in baking has a fixed memory cost on the CPU side. To reduce the risk of a crash caused by insufficient memory, consider joining high-poly objects before baking.

Next steps in an architectural visualization workflow

This workflow can be used to prepare reusable texture maps for architectural assets, bake lighting or AO data into an image, and transfer high levels of detail to a lower-poly model. The production goal determines the required output: if the model is going to be used in another environment, bake the relevant surface data; if the aim is to transfer scene lighting, choose the appropriate lighting bake type. In either case, UV layout and the correct target node are the first things to check.

When evaluating a bake, consider the source model’s detail, the layout of the UV islands, the ray distance or cage selection, and the margin together. Normal maps also require matching space settings: the Normal Space selected during baking must match the Normal Map setting in the Image Texture options. Tangent space is described as the default and generally appropriate choice; it can also be used for animated objects.

For office or student workflows, it’s useful to start by testing a small, representative part of the model and checking the UVs, target, and bake type. As the scene grows, reassess memory costs and seams in the output. The success of the workflow depends less on any single setting than on how well these preparations work together.

Sources and license

This guide was adapted into English from the “Render Baking” and “Image Texture Node” sections of the official Blender manual. Both sources are licensed under CC BY-SA 4.0. The source texts have been translated and adapted.