lua/convert-rawimg-to-font.lua

   1 lines = {};
   2 linelen = nil;
   3 linecount = 0;
   4
   5 component_encode = function(str)
   6         mult = 1;
   7         value = 0;
   8         for i = 1,#str do
   9                 if i % 8 == 1 then
  10                         mult = 1;
  11                         value = 256 * value;
  12                 end
  13                 if string.sub(str, i, i) == "1" then
  14                         value = value + mult;
  15                 end
  16                 mult = mult * 2;
  17         end
  18         if #str < 9 then
  19                 c2 = value % 93;
  20                 value = (value - c2) / 93;
  21                 c1 = value % 93;
  22                 return string.char(34 + c1, 34 + c2);
  23         elseif #str < 17 then
  24                 c3 = value % 93;
  25                 value = (value - c3) / 93;
  26                 c2 = value % 93;
  27                 value = (value - c2) / 93;
  28                 c1 = value % 93;
  29                 return string.char(37 + c1, 34 + c2, 34 + c3);
  30         elseif #str < 25 then
  31                 c4 = value % 93;
  32                 value = (value - c4) / 93;
  33                 c3 = value % 93;
  34                 value = (value - c3) / 93;
  35                 c2 = value % 93;
  36                 value = (value - c2) / 93;
  37                 c1 = value % 93;
  38                 return string.char(45 + c1, 34 + c2, 34 + c3, 34 + c4);
  39         elseif #str < 32 then
  40                 c5 = value % 93;
  41                 value = (value - c5) / 93;
  42                 c4 = value % 93;
  43                 value = (value - c4) / 93;
  44                 c3 = value % 93;
  45                 value = (value - c3) / 93;
  46                 c2 = value % 93;
  47                 value = (value - c2) / 93;
  48                 c1 = value % 93;
  49                 return string.char(66 + c1, 34 + c2, 34 + c3, 34 + c4, 34 + c5);
  50         end
  51 end
  52
  53 encode_letter = function(x, y, name)
  54         letter = prefix;
  55         for i = 1,cellheight do
  56                 letter = letter .. component_encode(string.sub(lines[y + i - 1], x, x + cellwidth));
  57         end
  58         print("!BEGIN " .. name);
  59         print("+" .. letter);
  60 end
  61
  62 for line in io.stdin:lines() do
  63         table.insert(lines, line);
  64         if linelen and #line ~= linelen then
  65                 error("Inconsistent line length");
  66         end
  67         linelen = #line;
  68         linecount = linecount + 1;
  69 end
  70
  71 if linecount == 0 or linecount % 6 ~= 0 then
  72         error("Line count must be positive and divisible by 6");
  73 end
  74
  75 if (linelen or 0) % 16 ~= 0 then
  76         error("Line length must be positive and divisible by 16");
  77 end
  78
  79 cellwidth = linelen / 16;
  80 cellheight = linecount / 6;
  81
  82 if cellwidth > 31 then
  83         error("Font too wide (max 31 pels)");
  84 end
  85
  86 prefix = string.char(34, 34 + cellwidth);
  87
  88 print("JRSR");
  89 for j=0,95 do
  90         x = j % 16;
  91         y = (j - x) / 16;
  92         encode_letter(cellwidth * x + 1, cellheight * y + 1, j + 32);
  93 end
  94 print("!END");