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|                    The Wing Commander Prophecy RLE Format                  |
|                           By Mario "HCl" Brito                             |
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Early Wing Commander games use RLE techniques to code it's images, and
Prophecy is no exception, so it's important to document how to decode
these images.

There are 2 types of RLE images in Prophecy: 8-bit and 16-bit RLE, and these
must be handled in a slightly different way. I will present below a C-like
routine that explains how to uncompress a 16-bit RLE:

1>      while (there's more RLE data to process)
2>              {
3>              func = readWord();
4>              size = readWord();
5>
6>              switch (func)
7>                      {
8>                      case 0:
9>                      repeat "size" times:
10>                             {
11>                             index = readWord();
12>                             color24 = palette[index];
13>                             store color24 in bitmap
14>                             }
15>                     break;
16>
17>                     case 1:
18>                     index = readWord();
19>                     color24 = palette[index];
20>                     repeat "size" times:
21>                             {
22>                             store color24 in bitmap
23>                             }
24>                     break;
25>
26>                     default:
27>                     skip "size" pixels in destination bitmap
28>                     }
29>             }

It seems odd to have a palette in 16-bit RLEs, but that's exactly what
happens, check pal files pal555.pal and pal565.pal

To unpack 8-bit RLEs, simply read bytes instead of words, the process is 
otherwise the same.


-> Thanks go to Origin Systems INC for creating Wing Commander Prophecy
   and Wing Commander Secret Ops. 


Mario "HCl" Brito
mbrito@student.dei.uc.pt