Civ PC-98 graphics formats (and potential Windows port)

Lord_Hill

Prince
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May 10, 2004
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Recently I've been investigating the possibility of porting the unique unit and terrain graphics from the little known Japan only PC-98 version of Civ over to the Windows version. This version is superficially similar to DOS (and plays the same) but with a couple of key differences. The resolution is doubled up to 640x400 (a nice feature of the PC-98 to better support the complicated Japanese character sets), but only 16 colours can be on screen at once. This means we get less colours than DOS VGA, but more detail thanks to the higher resolution and some nice dithering to work around the colour restrictions. Check out this shot of the intro as an example.
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Checking out the files themselves, we see a bunch of files with names that match the DOS version (and a few that don't), quite a few of them have the same PIC extension whereas others have a different SCP extension not used in the DOS version. Also no sign of anything matching the DOS tileset and unit graphics, there are no files named SP257, TER257 or SP299 here. There's a big problem though, these PIC files are not the same as the DOS ones! Attempting to open them in JCivEd won't get you anywhere. And even worse, none of my searches on various hacking and reverse engineering sites returned any results whatsoever. Reversing an unknown graphics format takes some serious skills so it appeared I was at a dead end.

Enter reverse engineer CanadianAvenger who had recently been spending a bunch of time looking at old Microprose graphics formats, and had taken a particular interest in PIC and how it had changed as it was used in different games. One game that took his interest was Railroad Tycoon Deluxe, an unusual release in that it was actually backported from the PC-98 version of Railroad Tycoon (itself an enhanced port of the original DOS version). It used a PIC format that was completely different from any he'd seen before, and you can see his painstaking reverse engineering efforts to understand it here.

It also used a previously unknown container format to hold multiple sprite images using the same PIC format, called SCP (does any of this sound familiar yet?) and he was able to once again work his magic to deduce how the format worked.

I happened to learn about this from chatting to someone on the Colonization discord and eventually got a Civ PC-98 PIC file over to him for investigation and sure enough, it was identical! This great news puts the Windows mod back on the table. Next I did a full comparison of the PC-98 files, matching them up with their DOS counterparts based on the names and some educated guesses. I've attached the spreadsheet of results, with nearly every file being matched to an equivalent DOS file (or files.)

The unfortunate news for me is that instead of using a couple of big PIC files covering all terrain, overlays and unit graphics like DOS, every single piece of terrain is stored as an individual 32x32 image in an SPC file, so there's a big jigsaw to be solved here as I need to identify each little piece and where it fits. Still, it'll keep me busy for a while at least :) TBC...
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Thanks! The actual terrain doesn't really make the most of it, it's pretty much the DOS terrain but dithered. But you get those sweet 32x32 sprites on top like the jungle and completely new unit artwork.
 
Here's an early wip screenshot. So far, the standard background tile and desert overlay are PC98, everything else is still Windows. Included a PC98 screen for comparison.
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This all makes me want to kinda sorta actually complete and officially™ release my icons mod thing because it's way overdue.
It also makes me want to play a couple of games of Civ1.
 
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