anchor.diff:            (gl:clear-color 0.0 0.0 1.0 1.0)
             (gl:clear :color-buffer)
   
  +          (format t "Opening game controllers.~%")
  +          (finish-output)
             ;; open any game controllers
             (loop for i from 0 upto (- (sdl2:joystick-count) 1)
                do (when (sdl2:game-controller-p i)
  
positive.code:               (haptic ()))
  
            ;; basic window/gl setup
            (sdl2:gl-make-current win gl-context)
            (gl:viewport 0 0 800 600)
            (gl:matrix-mode :projection)
  
negative.code:                         (sdl2:rumble-init h))))))
  
            ;; main loop
            (format t "Beginning main loop.~%")
            (finish-output)
            (sdl2:with-event-loop (:method :poll)
              (:keydown
               (:keysym keysym)
  