Mipmap
Pre-filtered texture down-sampling chain
Also known as: MIP map · Texture LOD · Mip chain
Definition
A mipmap is a chain of progressively smaller, pre-filtered versions of a texture, generated automatically at import. When the GPU samples a textured surface at a distance, it picks the appropriately-sized mip level rather than the full-resolution texture — avoiding both shimmering on distant surfaces and wasteful GPU bandwidth. Each level is 1/4 the area of the previous (half on each axis), so a 1024×1024 texture's mip chain totals about 1.33× the base size.
In production
Always enable mipmaps for in-world textures — surfaces viewed at varying camera distances, like ground, walls, and props — since without them distant textures shimmer badly under motion (a defect called texture aliasing). Disable them only for UI textures (rendered at fixed resolution on screen space) and some flipbook particle textures where bleeding between mip levels blurs frame boundaries and ruins the animation. UE5 and Unity both generate the full mip chain automatically at import using a box or Kaiser filter, and both let artists override the filter or add a mip bias per texture for sharper results at a performance cost. A common mistake is authoring tiling textures with strong contrast at the edges without testing the mip chain, since lower mips can visibly shift the average colour or introduce seams when tiled. Streaming virtual texturing systems, used in UE5's Nanite pipeline, rely on mipmaps even more heavily, since only the mip level needed for the current view is streamed from disk.
