A lower-level mip-map generator (36) generates portions of the mip-map which is next below, in the hierarchical series, the mip-map of which portions are held in the cache.

The lower-level mip-map generator (36) interpolates on the compressed code values.

As the name implies, mipnearest uses nearest-neighbor mipmapping, while miplinear uses linearly filtered mipmapping.

This lower level of mip-map texture image data is then stored for use in texturing.

A trilinear interpolator (34) interpolates one output texel from input texels from the two mip-map levels.

A controller (24) retrieves from the memory the mip-map data required and this data is stored in a cache (30).

A texturing system for use in a three-dimensional imaging system comprises a memory (22) for storing mip-map data for use in texturing an image.

A portion of the texture image data is stored temporarily and is filtered to generate at least one lower level of mip-map data from the texture data.

The textures are MIP-mapped and comprise a series of texture maps at different levels of detail, each map representing the appearance of the texture at a given distance from an eye point.