As the object becomes further from the point of gaze, the less detailed or lower resolution representations are used. These multi-resolution objects are rendered to a foveated pyramid where object detail level is selected according to the level within the pyramid. Furthermore, less processing time is required to translate, rotate, and scale lower resolution geometric objects, and less processing time is required to rotate, scale, and resample lower resolution images. 3D objects are stored as lists of polygons with their associated color information and texture maps. In order to achieve better performance, some simulators represent the same object with varying levels of detail.
Greater detail is represented with greater numbers of polygons and with higher resolution textures.
By representing objects in this way, overall polygon and texture processing requirements are reduced without sacrificing the detail of objects that appear close up. This same technique can also be used to select the detail level according to an object's distance from the point of gaze. Objects that are further from the point of gaze will have lower spatial resolutions, and therefore require less detail. Performance gain is seen because polygon and texture-map processing requirements are reduced for objects outside of the foveal region, even if the objects appear close to the viewer. Even without the use of multi-detailed object representation, a 3D scene could be rendered to a foveated pyramid and used as input to the foveated decoder similar to the 2D situation discussed above.