tbl/ti.c

   1 /* ti.c: classify line intersections */
   2 # include "t.h"
   3 /* determine local environment for intersections */
   4
   5 int
   6 interv(int i, int c)
   7 {
   8         int     ku, kl;
   9
  10         if (c >= ncol || c == 0) {
  11                 if (dboxflg) {
  12                         if (i == 0)
  13                                 return(BOT);
  14                         if (i >= nlin)
  15                                 return(TOP);
  16                         return(THRU);
  17                 }
  18                 if (c >= ncol)
  19                         return(0);
  20         }
  21         ku = i > 0 ? lefdata(i - 1, c) : 0;
  22         if (i + 1 >= nlin && allh(i))
  23                 kl = 0;
  24         else
  25                 kl = lefdata(allh(i) ? i + 1 : i, c);
  26         if (ku == 2 && kl == 2)
  27                 return(THRU);
  28         if (ku == 2)
  29                 return(TOP);
  30         if (kl == BOT)
  31                 return(2);
  32         return(0);
  33 }
  34
  35
  36 int
  37 interh(int i, int c)
  38 {
  39         int     kl, kr;
  40
  41         if (fullbot[i] == '=' || (dboxflg && (i == 0 || i >= nlin - 1))) {
  42                 if (c == ncol)
  43                         return(LEFT);
  44                 if (c == 0)
  45                         return(RIGHT);
  46                 return(THRU);
  47         }
  48         if (i >= nlin)
  49                 return(0);
  50         kl = c > 0 ? thish (i, c - 1) : 0;
  51         if (kl <= 1 && i > 0 && allh(up1(i)))
  52                 kl = c > 0 ? thish(up1(i), c - 1) : 0;
  53         kr = thish(i, c);
  54         if (kr <= 1 && i > 0 && allh(up1(i)))
  55                 kr = c > 0 ? thish(up1(i), c) : 0;
  56         if (kl == '=' && kr ==  '=')
  57                 return(THRU);
  58         if (kl == '=')
  59                 return(LEFT);
  60         if (kr == '=')
  61                 return(RIGHT);
  62         return(0);
  63 }
  64
  65
  66 int
  67 up1(int i)
  68 {
  69         i--;
  70         while (instead[i] && i > 0)
  71                 i--;
  72         return(i);
  73 }
  74
  75