Add back the Doom PWAD reload hack.

This was removed back in d190b596c566394717324296cbf6b46e67c64f5c;
at the time I didn't understand what it was or how it was supposed
to be used - it seemed like cruft left over from Doom's development.

It is actually a potentially useful feature for level authors when
developing their maps. See here: http://doomwiki.org/wiki/Reload_hack

The reload hack is a relatively obscure feature of limited usefulness
nowadays, but nonetheless a technical curiosity that ought to be
preserved in Chocolate Doom.

The reimplementation here is a lot cleaner than the original version
from the source release: W_Reload() is based on a call to W_AddFile(),
we don't reopen the reload file every time we want to read a lump,
and we include a check in W_AddFile() that we are not trying to use
the hack on more than one PWAD file.

This fixes #539.

0 files changed, 0 insertions, 0 deletions