Ultrix-3.1/src/libplot/t300s/line.c
/**********************************************************************
* Copyright (c) Digital Equipment Corporation 1984, 1985, 1986. *
* All Rights Reserved. *
* Reference "/usr/src/COPYRIGHT" for applicable restrictions. *
**********************************************************************/
/*
* SCCSID: @(#)line.c 3.0 4/22/86
*/
#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,command;
float xd,yd;
float dist2(),sqrt();
movep(cx0,cy0);
maxp = sqrt(dist2(cx0,cy0,cx1,cy1))/2.;
xd = cx1-cx0;
yd = cy1-cy0;
command = COM|((xd<0)<<1)|(yd<0);
if(maxp == 0){
xd=0;
yd=0;
}
else {
xd /= maxp;
yd /= maxp;
}
inplot();
spew(command);
for (tt=0; tt<=maxp; tt++){
chx= cx0+xd*tt-xnow;
xnow += chx;
chx = abval(chx);
chy = cy0+yd*tt-ynow;
ynow += chy;
chy = abval(chy);
spew(ADDR|chx<<3|chy);
}
outplot();
return;
}