ti.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright (c) 1980 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/
/*
* Copyright (c) 1983, 1984 1985, 1986, 1987, 1988, Sun Microsystems, Inc.
* All Rights Reserved.
*/
#ident "%Z%%M% %I% %E% SMI" /* SVr4.0 1.1 */
/* ti.c: classify line intersections */
# include "t..c"
/* determine local environment for intersections */
interv(i,c)
{
int ku, kl;
if (c>=ncol || c == 0)
{
if (dboxflg)
{
if (i==0) return(BOT);
if (i>=nlin) return(TOP);
return(THRU);
}
if (c>=ncol)
return(0);
}
ku = i>0 ? lefdata(i-1,c) : 0;
if (i+1 >= nlin)
kl=0;
else
kl = lefdata(allh(i) ? i+1 : i, c);
if (ku==2 && kl==2) return(THRU);
if (ku ==2) return(TOP);
if (kl==BOT) return(2);
return(0);
}
interh(i,c)
{
int kl, kr;
if (fullbot[i]== '=' || (dboxflg && (i==0 || i>= nlin-1)))
{
if (c==ncol)
return(LEFT);
if (c==0)
return(RIGHT);
return(THRU);
}
if (i>=nlin) return(0);
kl = c>0 ? thish (i,c-1) : 0;
if (kl<=1 && i>0 && allh(up1(i)))
kl = c>0 ? thish(up1(i),c-1) : 0;
kr = thish(i,c);
if (kr<=1 && i>0 && allh(up1(i)))
kr = c>0 ? thish(up1(i), c) : 0;
if (kl== '=' && kr == '=') return(THRU);
if (kl== '=') return(LEFT);
if (kr== '=') return(RIGHT);
return(0);
}
up1(i)
{
i--;
while (instead[i] && i>0) i--;
return(i);
}