Many thanks to this month's subscribers! Untangling Shuusou Gyoku's game logic into a library isn't the worst thing in the world, but still nontrivial. Will definitely end up closer to 2 pushes than to 1. Probably doing a bit of TH02 RE after that, given its recent funding.

github.com/nmlgc/rec98.... [💰] Confirm T0425 Ember2528 is also back with a smaller €50 subscription towards the better replay format for Shuusou Gyoku, followed by the previous long-term TH03 decompilation and porting roadmap! Thank you very much.

github.com/nmlgc/rec98.... [💰] Confirm T0424 Another €25 from iruleatgames towards reverse-engineering TH02 or getting it more position-independent, rounding up Yanga's earlier TH02 contributions to a full push. Thank you!

github.com/nmlgc/rec98.... [💰] Confirm T0423 €200 from iruleatgames towards reverse-engineering TH02, or getting it more position-independent! Thank you so much.

github.com/nmlgc/rec98.... [💰] Confirm T0422 €43.75 from Arandui towards Shuusou Gyoku's long overdue better replay feature, rounding us up to a full 3 pushes. Thank you very much!

🚚 TH03's enemy, fireball, explosion, chaining, and combo systems have been fully decompiled and researched! Hardest piece of game logic in all of PC-98 Touhou, by far. 1% of overall code, 6% of TH03 itself. 🐞 1 bug 💣 5 landmines 🎺 8 quirks 🪨 61 pieces of bloat

TH03 is about to get thoroughly analyzed and documented down to its core. ≥13,100 words. Heaviest blog post by HTML size so far. 2.36× more PC-98 Touhou reverse-engineering than the previously biggest RE post. Out in a few hours.

Almost done writing! Still need to spend some more coding time on the blog UX though, so that you can seamlessly switch between two layers of tabs and the 30 hitbox videos underneath. (Word count already above 10,000, by the way.)

Many thanks to this month's subscribers! Life priorities have shifted and I'll likely be even slower in the foreseeable future. Then again, what else is left in PC-98 Touhou that's as complex as TH03's enemies, fireballs, and explosions? Blog post should be out next week.

Bluesky confirmed for having the worst video processing pipeline in the entire social media landscape. Reducing *frame rates* is disgusting at a level that even Twitter wouldn't step down to.

Alright, TH03 formation code! I'm going to post all 18 scripts over the next few days. Structure/logic by ZUN, formation names by the gameplay community, function/parameter names by me, order as in ENEDAT.DAT. Videos recorded on Lunatic, where enemy speed equals script durations.

Imagine forking Nitter and running your own instance just to scrape your own alt text and polls because Twitter doesn't include either of them in its data archive. Oh well, Fediverse migration is complete. Please follow @[email protected] for the highest-quality images and videos.

Many thanks to this month's subscribers! TH03's enemy, fireball, and explosion code is in the very final stage of QA, but the blog post will still take a while. Life's been very slow lately. There'll be another exciting series of posts before then, though!

> Stumble over another MIDI sequencer that automatically decodes GS SysEx > OTAMA98 by MISO > Still works on Windows 11 > No bloat, no lengthy "analysis" phase, no hardware dongles, no bullshit > Even does XG! Though not as detailed… > …and GS support stops at SC-88, no Pro 😩

And yes, the extend glitch happens for the same reason once your score is ≥20 million and if that one segment lies at 0x3E?? (P1) or 0x2E?? (P2). And 0x2EF4 is exactly where the 2021 Ultimate Collection happens to place that segment if you play on anything other than DOSBox-X.

Found the cause of TH03's score reduction glitch! youtu.be/JltuH7nAO4Y?... It occurs on certain PC-98 setups if you destroy a fireball with anything that isn't an explosion on a frame where you previously got a VSync/PMD interrupt within a specific window of CPU instructions.

github.com/nmlgc/rec98.... [💰] Confirm T0414 Ember2528 is still with us, and once again bought all remaining capacity from the store! €154 towards his current long-term plan of Shuusou Gyoku replays followed by TH03 decompilation and porting. Thank you so much!

Many thanks to this month's subscribers! (As in, December's.) The current plan: 1) Lots of TH03 gameplay code (≥8.65% of MAIN.EXE) 2) Headless Shuusou Gyoku for automated replay validation 3) Probably a bit of TH02? Unless we've got clearer funding for something else by then.

🚚 Delivered a complete decompilation of and research into TH03's bullet system! A minor iteration on TH02's rather decent system, but definitely the point where bullet systems in PC-98 Touhou took a turn for the worse. 🐞 1 bug 💣 1 landmine 🎺 4 quirks 🪨 33 pieces of bloat

What was this delay. In exchange, I've got an unexpectedly long >6,500-word blog post about TH03's bullet system and a certain other issue, coming your way very soon. Fingers crossed I'll get it out while it's still 2025 in UTC.

TH03 Chiyuri has a very rare quirk where 1 or 2 bullets are randomly missing from the 48-ring pattern in her Level 1 or 2 Boss Attack if she launches it multiple times in a row. Explaining the cause certainly contributed to the massive delay of the upcoming blog post…

How to disqualify yourself for self-hosted archival storage: • Effectively prevent backdating by prioritizing crawl date in the AppView everyone uses • Importer insists on JPEG, and ignores tweets if you try PNG 🤮 Onto the Fediverse, then. activitypub.nmlgc.net/@rec98

The border between the two playfields in TH03 is not just visual, but an actual part of the simulated game world. Every transferred pellet or fireball physically travels through these 32 pixels before it appears on the other playfield.

Many thanks to this month's subscribers! Once again, the scope has expanded to include TH03's bullet and combo systems. Bullets are only missing one detail and will get a dedicated blogpost very soon. We're going to see at least 5 pushes and 10% more RE for MAIN.EXE in December.

TH03 decompilation will progress *so quickly* once I get the basic gameplay systems done. ZUN really did implement most of the character-specific systems by copy-pasting the same code 9 times with minor variations. That means ~3× the decompilation speed of TH01 at its fastest.

Many thanks to this month's subscribers! The next delivery will fully cover TH03's enemy, fireball, and explosion systems. No netplay this year though, Shuusou Gyoku replays have shaped up to be too complicated. (It might also make sense to have TH03 replays before netplay.)

While I'm working on TH03, let's design the replay format I'll use for Shuusou Gyoku and PC-98 Touhou! If there's anything you've ever wanted to see in a replay format, now's your chance to influence the design and feature set. github.com/nmlgc/ssg/is...

A landmark Neko Project 21/W release happened yesterday! SimK has finally murdered the horrible abomination that was the secondary set of ASCII glyphs in Neko Project's old auto-generated replacement for the PC-98 ROM font. twitter.com/simk98l/stat...

🚚 Delivered the planned Shuusou Gyoku maintenance release. SDL 3 is now a hard dependency (even on Windows 98!), the SDL 2 code path is gone, and the Linux version now compiles with GCC ≥15. No new features, but a few bugfixes and speedups surrounding screenshots and fonts.

Many thanks to this month's subscribers! The current plan for the rest of the year: 1) Shuusou Gyoku maintenance (will quickly free up some budget) 2) TH03 RE 3) Better replays for Shuusou Gyoku 4) TH03 netplay (would be nice to get it done by the end of the year)

🚚 Released the first version of the TH03 Anniversary Edition together with the first debloated builds of all five games! Primarily reduces lag in menus and cutscenes as a first step towards portability, but also comes with a single new feature. Download: github.com/nmlgc/ReC98/...

The end is near! >9,800 words, and probably the last big blog post for this year. I wanna code again! Out within the next few hours…

$ git diff --stat debloated~193 debloated […] 259 files changed, 4145 insertions(+), 8099 deletions(-) ~4,000 lines of ad-hoc PC-98-native graphics code, bloat, landmines, bloat- and landmine-documenting comments, and binary-specific inconsistencies removed from game code 🎉

🚚 Part 3 is out, bringing five disconnected and small decompilations and actually shifting the percentages on the front page for a change! 🐞 5 bugs 💣 3 landmines 🎺 2 quirks 🪨 24 pieces of bloat

> Next post is about five small and disconnected RE tasks > Try to write five short paragraphs with bullet points in the style of touhou-memories > Still end up with over 2,000 words Coming to you within the next few hours…

Part 2 of my 4-part 2025 PC-98 Touhou portability series is out! This one is also our second deep dive into PC-98 blitting performance with two new benchmarks, and also looks at the two libraries that ZUN used to load PI images. Not a lot of Touhou-specific content in this one.

Second part is in proofreading. Over 9,300 words about PC-98 blitting and the .PI format, coming to you within the next few hours…

📝 Wrote a post about the various strategies of porting PC-98 Touhou to modern platforms! Also clears up common misconceptions about the performance of the PC-98 originals. This one is required reading for anyone who wants to see these games ported. Link: rec98.nmlgc.net/blog/2025-09...

Trying something new this time! The next release touches on so many topics that one blog post would have been way too intense for everyone. So I'm splitting it up into 4 posts, with each focusing on a different topic. First part (~8,000 words) coming within the next few hours…

Many thanks to this month's subscribers! Code is done escalating, and now it's the blog post's turn. Got >13,000 words now and it's still missing lots of content… I'll be so relieved once I get to spend the rest of the year on TH03 and Shuusou Gyoku with no more distractions.

Here's all the ZUN quirks, bugs, landmines, and bloat from previously RE'd code that I missed or got wrong in previous pushes and fixed for the upcoming ones. Reverse-engineering is hard.

Testing completed.

Here's a funny script bug in TH04's Good Ending for Reimu A that I just stumbled over. ",4魔理沙"?! 🎺 (Third-party clip from 2013 for proof: www.youtube.com/clip/UgkxUo6...)

⚠️ Another Shuusou Gyoku Extra Stage replay desync bug? This time though, it's the actual catastrophic kind: An accidental fork of Marisa's gameplay that might invalidate replays recorded on any ReC98 build from the last 10 months, now that I've restored the original behavior.

Many thanks to this month's subscribers! 384 commits across 10 pushes coming your way soon… (Hopefully)

Alright, got to where I wanted to be. Merged the OP and MAINL/MAINE binaries of TH02-TH05 into a single one that's smaller than either of the original ones. No compression. And yes, they spawn missing drivers as needed. No GAME.BAT necessary. Also works with any PMD/MMD version.

Yup, we're going there again.

TH05's title screen crossfading effect is probably the most visible case of lag reduction in the upcoming ReC98 builds. Here's how the original game looks on Neko Project 21/W with a 66 MHz CPU, which is the usual recommended clock speed for emulating PC-98 Touhou:

The upcoming ReC98 builds will not only come with reduced lag in TH02-TH05 menus and cutscenes, but also bring a highly important quality-of-life feature to TH03: 🥁 Quitting out of the VS Start menu without going through the Select screen. 🙌

Fun fact: A TH04/TH05 GENSOU.SCR file that consists entirely of 00 bytes is valid and passes the game's checksum validation. Here's how such a file looks like in the High Score viewer, after the game spent way too much time rendering garbage data: