is
Checks if the angle formed between the points defined by the coordinates of the pertinent MotionEvents is indicative of a downward gesture.
A downward gesture is registered if the angle is in [0.25π, 0.75π).
Return
true if the angle formed between the points defined by the coordinates of the pertinent MotionEvents is indicative of a downward gesture.
Parameters
angle
Angle (in radians) formed between the points defined by the coordinates of the pertinent MotionEvents.