Axis constant: Orientation axis of a motion event.

• For a touch screen or touch pad, reports the orientation of the finger or tool in radians relative to the vertical plane of the device. An angle of 0 radians indicates that the major axis of contact is oriented upwards, is perfectly circular or is of unknown orientation. A positive angle indicates that the major axis of contact is oriented to the right. A negative angle indicates that the major axis of contact is oriented to the left. The full range is from -PI/2 radians (finger pointing fully left) to PI/2 radians (finger pointing fully right).
• For a stylus, the orientation indicates the direction in which the stylus is pointing in relation to the vertical axis of the current orientation of the screen. The range is from -PI radians to PI radians, where 0 is pointing up, -PI/2 radians is pointing left, -PI or PI radians is pointing down, and PI/2 radians is pointing right. See also Axis.Tilt.