line.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include "xroff.h"
   4
   5 /* horizontal and vertical line characters */
   6 static char *hs[] = {"_", "\\_", "\\-", "\\(ru", "\\(ul", "\\(rn", NULL};
   7 static char *vs[] = {"\\(bv", "\\(br", "|", NULL};
   8
   9 static int cwid(char *c)
  10 {
  11         struct glyph *g = dev_glyph(c, n_f);
  12         return charwid(g ? g->wid : SC_DW, n_s);
  13 }
  14
  15 static int lchar(char *c, char **cs)
  16 {
  17         while (*cs)
  18                 if (!strcmp(*cs++, c))
  19                         return 1;
  20         return 0;
  21 }
  22
  23 static void vmov(struct adj *adj, int w)
  24 {
  25         adj_put(adj, w, "\\v'%du'", w);
  26 }
  27
  28 static void hmov(struct adj *adj, int w)
  29 {
  30         adj_put(adj, w, "\\h'%du'", w);
  31 }
  32
  33 void ren_hline(struct adj *adj, char *arg)
  34 {
  35         char *lc = "\\(ru";
  36         int w, l, n, i, rem;
  37         l = eval_up(&arg, 0, 'm');
  38         if (!l)
  39                 return;
  40         if (arg[0] == '\\' && arg[1] == '&')    /* \& can be used as a separator */
  41                 arg += 2;
  42         if (*arg)
  43                 lc = arg;
  44         w = cwid(lc);
  45         /* negative length; moving backwards */
  46         if (l < 0) {
  47                 hmov(adj, l);
  48                 l = -l;
  49         }
  50         n = l / w;
  51         rem = l % w;
  52         /* length less than character width */
  53         if (l < w) {
  54                 n = 1;
  55                 rem = 0;
  56                 hmov(adj, -(w - l) / 2);
  57         }
  58         /* the initial gap */
  59         if (rem) {
  60                 if (lchar(lc, hs)) {
  61                         adj_put(adj, w, "%s", lc);
  62                         hmov(adj, rem - w);
  63                 } else {
  64                         hmov(adj, rem);
  65                 }
  66         }
  67         for (i = 0; i < n; i++)
  68                 adj_put(adj, w, lc);
  69         /* moving back */
  70         if (l < w)
  71                 hmov(adj, -(w - l + 1) / 2);
  72 }
  73
  74 void ren_vline(struct adj *adj, char *arg)
  75 {
  76         char *lc = "\\(br";
  77         int w, l, n, i, rem, hw, neg;
  78         l = eval_up(&arg, 0, 'm');
  79         if (!l)
  80                 return;
  81         neg = l < 0;
  82         if (arg[0] == '\\' && arg[1] == '&')    /* \& can be used as a separator */
  83                 arg += 2;
  84         if (*arg)
  85                 lc = arg;
  86         w = n_s * SC_PT;        /* character height */
  87         hw = cwid(lc);          /* character width */
  88         /* negative length; moving backwards */
  89         if (l < 0) {
  90                 vmov(adj, l);
  91                 l = -l;
  92         }
  93         n = l / w;
  94         rem = l % w;
  95         /* length less than character width */
  96         if (l < w) {
  97                 n = 1;
  98                 rem = 0;
  99                 vmov(adj, -w + l / 2);
 100         }
 101         /* the initial gap */
 102         if (rem) {
 103                 if (lchar(lc, vs)) {
 104                         vmov(adj, w);
 105                         adj_put(adj, hw, "%s", lc);
 106                         hmov(adj, -hw);
 107                         vmov(adj, rem - w);
 108                 } else {
 109                         vmov(adj, rem);
 110                 }
 111         }
 112         for (i = 0; i < n; i++) {
 113                 vmov(adj, w);
 114                 adj_put(adj, hw, lc);
 115                 hmov(adj, -hw);
 116         }
 117         /* moving back */
 118         if (l < w)
 119                 vmov(adj, l / 2);
 120         if (neg)
 121                 vmov(adj, -l);
 122         hmov(adj, hw);
 123 }