Touch interface represents a single contact point on a touch-sensitive device. The contact point is commonly a finger or stylus and the device may be a touchscreen or trackpad.
Touch.rotationAngle describe the area of contact between the user and the screen, the touch area. This can be helpful when dealing with imprecise pointing devices such as fingers. These values are set to describe an ellipse that as closely as possible matches the entire area of contact (such as the user's fingertip). Experimental
Note: Many of the properties' values are hardware-dependent; for example, if the device doesn't have a way to detect the amount of pressure placed on the surface, the
force value will always be 0. This may also be the case for
radiusY; if the hardware reports only a single point, these values will be 1.