ScreenTapGesture = function(data) {
 /**
  * The position where the screen tap is registered.
  *
  * @member position
  * @memberof Leap.ScreenTapGesture.prototype
  * @type {number[]}
  */
  this.position = data.position;
 /**
  * The direction of finger tip motion.
  *
  * @member direction
  * @memberof Leap.ScreenTapGesture.prototype
  * @type {number[]}
  */
  this.direction = data.direction;
 /**
  * The progess value is always 1.0 for a screen tap gesture.
  *
  * @member progress
  * @memberof Leap.ScreenTapGesture.prototype
  * @type {number}
  */
  this.progress = data.progress;
}
Constructs a new ScreenTapGesture object.

An uninitialized ScreenTapGesture object is considered invalid. Get valid instances
of the ScreenTapGesture class from a Frame object.

@class ScreenTapGesture
@memberof Leap
@augments Leap.Gesture
@classdesc
The ScreenTapGesture class represents a tapping gesture by a finger or tool.

A screen tap gesture is recognized when the tip of a finger pokes forward
and then springs back to approximately the original postion, as if
tapping a vertical screen. The tapping finger must pause briefly before beginning the tap.

![ScreenTap](images/Leap_Gesture_Tap2.png)

ScreenTap gestures are discrete. The ScreenTapGesture object representing a tap always
has the state, STATE_STOP. Only one ScreenTapGesture object is created for each
screen tap gesture recognized.