BSD 4_4 release

[unix-history] / usr / src / lib / libplot / t300 / line.c

/*-
* Copyright (c) 1983, 1993
*      The Regents of the University of California.  All rights reserved.
*
* This module is believed to contain source code proprietary to AT&T.
* Use and redistribution is subject to the Berkeley Software License
* Agreement and your Software Agreement with AT&T (Western Electric).
*/

#ifndef lint
static char sccsid[] = "@(#)line.c      8.1 (Berkeley) 6/4/93";
#endif /* not lint */

#include "con.h"
line(x0,y0,x1,y1){
       iline(xconv(xsc(x0)),yconv(ysc(y0)),xconv(xsc(x1)),yconv(ysc(y1)));
               return;
}
cont(x0,y0){
       iline(xnow,ynow,xconv(xsc(x0)),yconv(ysc(y0)));
       return;
}
iline(cx0,cy0,cx1,cy1){
       int maxp,tt,j,np;
       char chx,chy;
       float xd,yd;
       double dist2(),sqrt();
               movep(cx0,cy0);
               maxp = sqrt(dist2(cx0,cy0,cx1,cy1))/2.;
               xd = cx1-cx0;
               yd = cy1-cy0;
               if(xd >= 0)chx = RIGHT;
               else chx = LEFT;
               if(yd >= 0)chy = UP;
               else chy = DOWN;
               if(maxp==0){
                       xd=0;
                       yd=0;
               }
               else{
                       xd /= maxp;
                       yd /= maxp;
               }
               inplot();
               for (tt=0; tt<=maxp; tt++){
                       j= cx0+xd*tt-xnow;
                       xnow += j;
                       j = abval(j);
                       while(j-- > 0)spew(chx);
                       j = cy0+yd*tt-ynow;
                       ynow += j;
                       j = abval(j);
                       while(j-- > 0)spew(chy);
                       spew ('.');
               }
               outplot();
               return;
}