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Scaling transformation bug???

Some graphical output is missing in my application when I use a
scaling transformation, MAKE-SCALING-TRANSFORMATION, it seems that
with some scaling factor, things don't get drawn at all - is that a
"feature" or a bug?  This seems to occur only when something get
scaled to a thickness of 1 pixel.

The code below will illustrate the bug, you'll see 11 gaps with the
default case, if you change the argument, Y-SCALE to something else, eg.
.15, there's only 1 gap.  If it is .2, there is no gap, but the
thickness varies.  Although the test below only demonstrate the
problem in the X axes, it occurs in the Y direction as well.

platform: SUN IPC     LUCID CL 4.1   CLIM 1.1
(also in ALLEGRO 4.1 + CLIM 1.1, but no gaps for .15 - prolly due to
the fact that DECF gives different results! - try
(loop with i = 0.1 
      for j from 1 to 10 do (print (decf i .0003))) )

(defun test (&optional (y-scale .1))
  (let ((window (clim::open-window-stream :width 650 :height 500
		   :parent (clim::open-root-window :clx :host "sunstruck.isi.edu"))))
			;;                 change to your machine ^^^^^^^^^^^^^
    (clim::window-expose window)

    (loop do 
	  (clim::window-clear window)
	  (loop for x from 1 to 600 by 20 do
		(clim::with-drawing-options (window :transformation
						    (clim::make-scaling-transformation 1 y-scale))
		  (clim::draw-rectangle* window (1- x) 2000 (+ x 18) 2007)
		  (decf y-scale 0.0003)
		  (clim::finish-output window)))
	  (restart-case (clim::accepting-values (window :own-window t)
				 (setq y-scale (clim::accept 'float :default y-scale
							     :prompt "New Y scaling factor"
							     :stream window)))
	   (abort () (clim::close window) (return-from test))))))

Chee.




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