Subversion Repositories planix.SVN

/* ti.c: classify line intersections */
# include "t.h"
/* determine local environment for intersections */

int
interv(int i, int 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 && allh(i))
                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);
}


int
interh(int i, int 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);
}


int
up1(int i)
{
        i--;
        while (instead[i] && i > 0) 
                i--;
        return(i);
}