EGAHEAD bug

ModKeen mods Tiles and Sprites in all episodes of Commander Keen.
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levellass
Posts: 2841
Joined: Wed Oct 11, 2006 12:03 pm
Location: Ngaruawahia New Zealand

EGAHEAD bug

Post by levellass » Fri Nov 26, 2010 6:02 am

So after some confusion and annoyance exporting Modkleen created graphics, I discovered something interesting.

Firstly, Modkeen doesn't put the last slot into EGAHEAD. That is, the word giving the length of EGAGRAPH. It is thus 3 bytes shorter than it should be. Fortunately this doesn't have many effects.

However, with Keen Dreams it is four slots short, (8 bytes since KD uses 4-byte slots) which actually means several tiles in KD aren't patched. This means any level using the last four tiles, and they are used, they're some of the fire tiles, crashes. It also gives problems when exporting graphics.

Just thought I'd leave this out there in case anyone else comes across similar bugs when making their own programs.

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