xfd_PacPic

Short:        Sources of Pac.Pic. xfdmaster client
Author:       Kyzer/CSG <kyzer@4u.net>, François Lionet
Uploader:     Kyzer/CSG <kyzer 4u net>
Type:         dev/src
Requires:     util/pack/xfdmaster.lha
Architecture: m68k-amigaos

This is the source code of XFD's Pac.Pic. slave, for the curious.

Pac.Pic. is an Amiga picture compression module used in AMOS Basic. It was
created by François Lionet. The code for this slave is based on the
original source code for the picture compactor extension, which came
bundled with AMOS 1.3 all those years ago.

Pac.Pic. is simply an RLE compressor, that re-orders the screen before
compression in a way which favours large vertical lumps of colour. It
RLE-encodes the reordered screen without using a special marker code,
but rather one bit for every byte on the screen to say if it's a repeat
or not. This large list of bits is then itself RLE encoded, which brings
down the size quite a lot.

This XFD slave 'decrunches' the picture to the uncompressed IFF ILBM
picture format.