Radial Direction

In auditory-display research, a data value that represents a direction in a plane — for example a compass bearing, the tangent of a curve, or the orientation of a pointer — treated as an angle rather than as a pair of Cartesian coordinates. Radial values are inherently circular (0° and 360° are the same direction), which makes them awkward to sonify with linear sound properties such as pitch. Mapping radial directions directly to two-dimensional sound spaces (e.g., vowel formants or spatialised audio) is useful for eyes-free navigation, path tracing, and homing-beacon applications for blind users.