xref: /csrg-svn/lib/libplot/grn/space.c (revision 61391)
148511Sbostic /*-
2*61391Sbostic  * Copyright (c) 1980, 1986, 1993
3*61391Sbostic  *	The Regents of the University of California.  All rights reserved.
448511Sbostic  *
548511Sbostic  * %sccs.include.proprietary.c%
629816Ssklower  */
729816Ssklower 
829816Ssklower #ifndef lint
9*61391Sbostic static char sccsid[] = "@(#)space.c	8.1 (Berkeley) 06/04/93";
1048511Sbostic #endif /* not lint */
1129816Ssklower 
1229816Ssklower #include "grnplot.h"
1329816Ssklower 
1429816Ssklower /*---------------------------------------------------------
1529816Ssklower  *	Space sets up the world-to-screen transformation so
1629816Ssklower  *	that the rectangular area described by (x0, y0) and
1729816Ssklower  *	(x1, y1) will all be on-screen.
1829816Ssklower  *
1929816Ssklower  *	Results:	None.
2029816Ssklower  *
2129816Ssklower  *	Side Effects:
2229816Ssklower  *	Our own variables scale, xbot, and ybot are changed.
2329816Ssklower  *---------------------------------------------------------
2429816Ssklower  */
space(x0,y0,x1,y1)2529816Ssklower space(x0, y0, x1, y1)
2629816Ssklower int x0, y0, x1, y1;
2729816Ssklower {
2829816Ssklower     double xscale=0.0, yscale=0.0;
2929816Ssklower     if (x1>x0)
3029816Ssklower 	    xscale = GRXMAX/(double)(x1-x0);
3129816Ssklower     if (y1>y0)
3229816Ssklower 	    yscale = GRYMAX/(double)(y1-y0);
3329816Ssklower     scale = (xscale > yscale && yscale > 0)? yscale : xscale;
3429816Ssklower     if (scale == 0.0) scale == 1.0;
3529816Ssklower     xbot = x0;
3629816Ssklower     ybot = y0;
3729816Ssklower }
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