Textures
For a full reference on texture formats and settings, see the official documentation.
Texture Resolution
Always use power-of-two dimensions: 64, 128, 256, 512, 1024, 2048, 4096, etc. Textures do not have to be square — mixing powers of two is fine (e.g. 1024×512).
Power-of-two resolutions are required for:
- GPU compression — non-power-of-two textures cannot be compressed, which means they take significantly more GPU memory.
- Mipmaps — Unreal generates mip levels by halving the resolution at each step; this only works correctly with power-of-two sizes.
- Streaming — the texture streaming system relies on mip levels to load the appropriate resolution at runtime.
Compression
Choosing the right compression setting reduces GPU memory usage without visible quality loss. In Unreal Engine the compression is set per texture in the texture editor.
| Compression Setting | Format | Use case |
|---|---|---|
| Default | BC1 / BC3 | Color / albedo textures (BC1 without alpha, BC3 with alpha) |
| Normalmap | BC5 | Normal maps — stores only R and G channels, B is reconstructed |
| Masks | BC4 | Single-channel masks — roughness, metallic, ambient occlusion |
| HDR | BC6H | HDR environment textures |
| UserInterface2D | — | UI textures, no mipmaps generated |
Rule of thumb: never leave a texture on Default compression if it is a normal map or a single-channel mask — you waste memory and may get rendering artifacts.
Texture Group
The Texture Group (also called LOD Group) controls how Unreal streams and manages a texture at runtime. It sets the streaming priority, mipmap bias, and maximum allowed resolution for a group of textures.
Setting the correct Texture Group ensures:
- The streaming system loads the right resolution at the right time.
- High-priority surfaces (characters, weapons) keep full resolution longer than background props.
- You can cap resolutions per group in the device profile, making it easy to scale quality across platforms without touching individual assets.
Common Texture Groups:
| Group | Typical use |
|---|---|
| World | Environment / architectural surfaces |
| WorldNormalMap | Normal maps for environment meshes |
| Character | Character skin and clothing |
| CharacterNormalMap | Normal maps for characters |
| Effects | VFX textures, particles |
| UI | Interface elements |
Always assign the most specific group that matches the texture’s purpose — do not leave everything on the default World group.