.TH gl_bcircle 3 "4 Dec 1999" "Svgalib (>= 1.4.1)" "Svgalib User Manual" .SH NAME gl_bcircle \- draw a filled or unfilled Bresenham circle .SH SYNOPSIS .B #include .BI "void gl_bcircle(int " x ", int " y ", int " r ", int " c ", int " fill ");" .SH DESCRIPTION Draw a Bresenham circle of radius .I r in color .I c , centered at .I ( x ", " y ). .I Fill should be 0 for a hollow circle, or any other value for a solid color. 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, .I 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. .SH SEE ALSO .BR svgalib (7), .BR vgagl (7), .BR svgalib.conf (5), .BR threedkit (7), .BR testgl (1), .BR plane (1), .BR wrapdemo (1), .BR gl_circle (3), .BR gl_clearscreen (3), .BR gl_colorfont (3), .BR gl_disableclipping (3), .BR gl_enableclipping (3), .BR gl_fillbox (3), .BR gl_fillcircle (3), .BR gl_hline (3), .BR gl_line (3), .BR gl_setclippingwindow (3), .BR gl_setpalette (3), .BR gl_setpalettecolor (3), .BR gl_setpalettecolors (3), .BR gl_setpixel (3), .BR gl_setpixelrgb (3), .BR gl_setrgbpalette (3), .BR gl_setwritemode (3). .SH AUTHOR This manual page was written by Jay Link .