Free Hero Mesh class resource file
A Free Hero Mesh puzzle set consists of four files; this article is about the .xclass file, which contains pictures and sounds.
This file is a Hamster archive which contains lumps with extension .IMG and .DEP and .MUL and .WAV.
The .IMG lumps are pictures, using a specialized compression format. Each such lump can store multiple versions of the picture at different sizes (which must be square, but otherwise can be arbitrary), and use a fixed palette of 255 colours plus transparency.
The .DEP lumps reference .IMG lumps and produce a picture made by modifying and/or combining the pictures in the .IMG lumps.
The .MUL lumps also reference .IMG lumps, but produce multiple pictures from them. It defines one list of bases and three lists of filter chains, and each combination of one from each list produces a picture; for example, if there are ten bases, ten first filter chains, four second filter chains, and three third filter chains, then it will produce 1200 pictures in total.
The .WAV lumps are WAVE audio files.
The PICEDIT.CFG lump contains configuration data for the picture editor. It can safely be deleted (the picture editor will still work even if this is deleted).