There is an array of numSkins skin names stored at offsetSkins into the file.
Each skin name is a char[64]. The name is really a path to the skin,
relative to the base game directory (baseq2 f or "standard" Quake2).
The skin files are regular pcx files.

@author Johann Sorel

These two shorts are used to map a vertex onto a skin.
The horizontal axis position is given by s, and the vertical axis position is given by t.
The range for s is greater than or equal to 0 and less than skinWidth (0 <= s < skinWidth).
The range for t is greater than or equal to 0 and less than skinHeight (0 <= s < skinHeight).
Note that the ranges are different than in the s and t members of the glCommandVertex structure.