getAngle( p1, p2 ) {

		return Math.atan2( p2.clientY - p1.clientY, p2.clientX - p1.clientX ) * 180 / Math.PI;

	}
Calculate the angle between two pointers.

@private
@param {PointerEvent} p1 - The first pointer event.
@param {PointerEvent} p2 - The second pointer event.
@returns {number} The angle between two pointers in degrees.