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       gl_bcircle - draw a filled or unfilled Bresenham circle


       #include <vgagl.h>

       void gl_bcircle(int x, int y, int r, int c, int fill);


       Draw  a  Bresenham circle of radius r in color c , centered at ( x ,  y

       Fill should be 0 for a hollow circle, or any other value  for  a  solid

       This  function differs from gl_circle (3) and gl_fillcircle (3) in that
       it looks good in 320 x 200 screen modes.  The  modified  algorithm  was
       provided  by  Chris  Atenasio  <>,  and  is based upon
       Bresenham’s formula.

       Note that the "circle" is technically an ellipse, and is actually wider
       than  it  is tall. Therefore, r is equal to the circle’s height, but is
       less than its width. This distortion is necessary to accomodate the 8:5
       aspect ratio (e.g., 320 x 200).

       I  don’t  recommend  using  this  function in standard 4:3 screen modes
       (e.g., 640 x 480 and higher). Furthermore, care must be taken so that a
       circle  drawn  with  this  function  isn’t  copied  to  a screen with a
       different aspect ratio. Otherwise, the result may be undesirable.


       svgalib(7),   vgagl(7),   svgalib.conf(5),   threedkit(7),   testgl(1),
       plane(1),       wrapdemo(1),      gl_circle(3),      gl_clearscreen(3),
       gl_colorfont(3),      gl_disableclipping(3),      gl_enableclipping(3),
       gl_fillbox(3),      gl_fillcircle(3),      gl_hline(3),     gl_line(3),
       gl_setclippingwindow(3),    gl_setpalette(3),    gl_setpalettecolor(3),
       gl_setpalettecolors(3),        gl_setpixel(3),       gl_setpixelrgb(3),
       gl_setrgbpalette(3), gl_setwritemode(3).


       This manual page was written by Jay Link <>.