For a basic introduction to clipmaps, see Clipmaps (Wikipedia).

The clipmap can store geometry information (e.g. heights, normals, holes) or material information (e.g. diffuse color, specular color). The usage of a clipmap can vary and is not defined by this class itself. The only restriction is that all textures of this clipmap use the same texture format.

The clipmap consists of several levels, which are similar to mipmap levels. Level 0 has the finest resolution. All other levels have a lower resolution. The cell size (= texel size) is usually doubled between levels, but this can be configured using the property CellSizes. For example: A clipmap which stores terrain height values can use a resolution of 1 meter per cell at level 0, 2 meters per cell at level 1, 4 meters per cell at level 2, etc.

There is one texture for each clipmap level. All texture have the same size which is defined by CellsPerLevel. The number of levels is defined by NumberOfLevels.

Further a clipmap can consist of several textures per level, e.g. one texture to store detail normal vectors, a second texture to store diffuse color, a third texture to store specular color. Because of XNA limitations it might be necessary to combine several textures into a single texture atlas, where each texture atlas contains all levels with the same content. For example: One texture atlas contains all level textures with detail normal vectors, a second texture atlas contains all level textures with diffuse colors, the third texture atlas contains all level textures with specular colors. - All textures can be accessed using the Textures collection. (It can be helpful to visualize the textures for debugging).

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