Sets the given joystick's y-inversion. If invert is set to false (the default behaviour), pressing the joystick up will return positive values while pressing the joystick down will return negaive values. Setting invert to true will reverse this logic.
PRVirconJoySetYInvert(joyId, invert) 
The joystick ID.
true or false, indicating whether the returned joystick values are inverted or not.
n/a