- joystick-get-ball joystick ball-numprocedure
See SDL_JoystickGetBall.
This procedure returns multiple values.
Signals an exception of kind (exn bounds) if ball-num is less than 0 or greater than the last trackball on the joystick (see joystick-num-balls). Signals an exception of kind (exn sdl2) if some other error occurs.