sample/rcs.awk

   1 BEGIN {
   2     sw = 40.0;
   3     dw = 78.0;
   4     hdw = dw / 2.0;
   5     w = 20.0;
   6     h =1.0;
   7     d = 0.2;
   8     ss="abcdefghijklmnopqrstuvwxyz0123456789!#$%^&*()-=\\[];'`,./";
   9     rnd = srand();
  10 }
  11
  12 {
  13     xr = -hdw; y = h * 1.0; maxxl = -999;
  14     s = "";
  15     while (xr < hdw) {
  16         x = xr * (1 + y) - y * w / 2;
  17         i = (x / (1 + h) + sw /2);
  18         c = (0 < i && i < length($0)) ? substr($0, i, 1) : "0";
  19         y = h - d * c;
  20         xl = xr - w * y / (1 + y);
  21         if (xl < -hdw || xl >= hdw || xl <= maxxl) {
  22             t = rand() * length(ss);
  23             c = substr(ss, t, 1);
  24         }
  25         else {
  26             c = substr(s, xl + hdw, 1);
  27             maxxl = xl;
  28         }
  29         s = s c;
  30         xr = xr + 1;
  31     }
  32     print s;
  33 }