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; Simplest possible OpenGL example
;

;; a trivial opengl draw loop
(definec my-gl-loop
  (let ((size 0.01))
    (lambda (degree)
      (glClear (+ GL_COLOR_BUFFER_BIT GL_DEPTH_BUFFER_BIT))
      (glLoadIdentity)
      (glTranslated 0.0 -1.0 0.0)
      (let ((i:double 0.0))
	(dotimes (i 1000.0)
	  (glTranslated (/ i 2000.0) 0.0 0.0)
	  (glColor3d (/ i 1500.0) 0.0 1.0)
	  (glRotated degree (/ i 200000.0) 0.5 0.0)
	  (glBegin GL_QUADS)
	  (glVertex2d 0.0 0.0)
	  (glVertex2d size 0.0)
	  (glVertex2d size size)
	  (glVertex2d 0.0 size)       
	  (glEnd))))))

;; standard impromptu callback                                                
(define opengl-test
  (lambda (degree)
    (my-gl-loop degree)
    (gl:swap-buffers glctx)
    (callback (+ (now) 500) 'opengl-test (+ degree .005))))

(define glctx (gl:make-ctx ":0.0" #f 0.0 0.0 1024.0 768.0))
(opengl-test 70.0)