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📝 Posted:
🚚 Summary of:
P0117
Commits:
03048c3...0bb5bc3
💰 Funded by:
[Anonymous]

Wouldn't it be a bit disappointing to have TH05 completely position-independent, but have it still require hex-editing of the original ZUN.COM to mod its gaiji characters? As in, these custom "text" glyphs, available to the PC-98 text RAM:

Especially since we now even have a sprite converter… the lack of which was exactly 📝 what made rebuilding ZUN.COM not that worthwhile before. So, before the big release, let's get all the remaining ZUN.COM sub-binaries of TH04 and TH05 dumped into .ASM files, and re-assembled and linked during the build process.

This is also the moment in which Egor's 2018 reimplementation of O. Morikawa's comcstm finally gets to shine. Back then, I considered it too early to even bother with ZUN.COM and reimplementing the .COM wrapper that ZUN originally used to bundle multiple smaller executables into that single binary. But now that the time is right, it is nice to have that code, as it allowed me to get these rebuilds done in half a push. Otherwise, it would have surely required one or two dedicated ones.

Since we like correctness here, newly dumped ZUN code means that it also has to be included in the RE% baseline calculation. This is why TH04's and TH05's overall RE% bars have gone back a tiny bit… in case you remember how they previously looked like :tannedcirno: After all, I would like to figure out where all that memory allocated during TH04's and TH05's memory check is freed, if at all.


Alright, one half of a push left… Y'know, getting rid of those last few PI false positives is actually one of the most annoying chores in this project, and quite stressful as well: I have to convince myself that the remaining false positives are, in fact, not memory references, but with way too little time for in-depth RE and to denote what they are instead. In that situation, everyone (including myself!) is anticipating that PI goal, and no one is really interested in RE. (Well… that is, until they actually get to developing their mod. But more on that tomorrow. :onricdennat:) Which means that it boils down to quite some hasty, dumb, and superficial RE around those remaining numbers.

So, in the hope of making it less annoying for the other 4 games in the future, let's systematically cover the sources of those remaining false positives in TH05, over all games. I/O port accesses with either the port or the value in registers (and thus, no longer as an immediate argument to the IN or OUT instructions, which the PI counter can clearly ingore), palette color arithmetic, or heck, 0xFF constants that obviously just mean "-1" and are not a reference to offset 0xFF in the data segment. All of this, of course, once again had a way bigger effect on everything but an almost position-independent TH05… but hey, that's the sort of thing you reserve the "anything" pushes for. And that's also how we get some of the single biggest PI% gains we have seen so far, and will be seeing before the 100% PI mark. And yes, those will continue in the next push.

Alright! Big release tomorrow…