Ideally, programs should always use textures that have high enough resolution to allow magnification without blurring. High-resolution textures maintain realistic image quality for both close-up and distant views. For example, in a high-resolution road texture, the large features--such as potholes, oil stains, and lane markers that are visible from a distance--as well as the asphalt of the road surface, look realistic no matter where the viewpoint is.
Unfortunately, a high-resolution road texture with that much detail may be as large as
2K x 2K, which may exceed the texture storage capacity of the system. Making the image close to or equal to the maximum allowable size still leaves little or no memory for the other textures in the scene.
The detail texture extension provides a solution for representing a 2K x 2K road texture with smaller textures. Detail texture works best for a texture with high-frequency information that is not strongly correlated to its low-frequency information. This occurs in images that have a uniform color and texture variation throughout, such as a field of grass or a wood panel with a uniform grain. If high-frequency information in your texture is used to represent edge information (for example, a stop sign or the outline of a tree) consider the sharpen texture extension (see "The Sharpen Texture Extension").