This function is used to get the speed required for a Flick Gesture event to be triggered when a touch or click is released. The speed is measured in inches per second and has a default value of 2.0.
Real (inches per second)
if gesture_get_flick_speed() != 2
The above code checks to see if the flick speed for gestures is set to 2 inches per second and if it is not it sets it to that value.