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:

Let's check the general community sentiment toward a crucial PC-98 Touhou portability question! This is how screen fade effects look in the original games. They work by manipulating the 16-color hardware palette within its 12-bit RGB444 color space.

Players have reported several score bugs in TH03 I've yet to look into, but here's an obscure one I just found. ZUN didn't look at the last digit when sorting new scores into the High Score list 🎺 Identical scores with different credit counts always appear in insertion order.

Many thanks to this month's subscribers! Not posting a lot here only means I'm working on something huge. Up to 261 commits now, more than half of them on master, and nearing feature completion. Releasing mid-July, probably? Still got lots of testing and explaining to do…

When you realize that the PC-98 has 768×4 bytes of offscreen VRAM instead of just the 80×4 bytes that ZUN used for this effect:

Wait, BERO's PiLoad library (used in TH01) is more than 2× as fast as master.lib's PI functions (used in TH02 and later)? Yup. A masterclass in x86 optimization. 🙇 ZUN may have just switched because PiLoad only loads to VRAM and not memory, but that feature is quickly added.

Many thanks to this month's subscribers! Currently deeply submerged in portability and code cleanup issues. Let's hope I resurface soon…

It sure takes a bit of effort to fix all the screen tearing landmines in PC-98 Touhou while still maintaining the exact original frame timing. The resulting code is often not natural at all.

Fixed two replay bugs in the ReC98 Shuusou Gyoku build: • Extra Stage replays recorded in ≥P0295 were highly likely to desync • ≥P0217 saved twice as many replay frames as necessary Watching an affected replay in the new build will repair the desync and recompress the file.

🚚 TH03's OP.EXE has been fully decompiled, completing the last missing main menu of PC-98 Touhou! This one comes with a few unused labels, and demos that point us to unexpected additional replay value?👀 🐞 1 bug 💣 2 landmines 🎺 1 quirk 🪨 35 pieces of bloat

This time, I've got 2,900 words about TH03's main menu, a certain unexpected gameplay detail that will make netplay even more interesting, and the usual plans for the immediate future. Coming to you in the next few hours.

Many thanks to this month's subscribers! I'd like to pause Shuusou Gyoku until August, so we'll have lots of netplay-focused TH03 progress in the next few months. But there's enough funding to occasionally work on specific small things in any of the other 4 games if requested.

github.com/nmlgc/rec98.... [💰] Confirm T0372 €5 from Koa towards reconstructing the original installers of the PC-98 Touhou games? That'll probably capture a good chunk of the Anything funding at some point. Thank you!

TH03's three KeyConfig modes (Key vs Key, Joy vs Key, and Key vs Joy) had much less descriptive labels at some earlier point in development.

🚚 Delivered the initial release of Shuusou Gyoku's backport to Windows 98, this time with all sound- and input-related enhancements from the modern build! It might not run perfectly on pure Windows 98 yet, but it does already run on unmodified Windows XP.

I know, I know, you're all eagerly waiting for TH03 to really get going and become ready for netplay. Just one more 5,700-word blog post about the Shuusou Gyoku backport to Windows 98 and then we're finally going to stay with TH03 for a few months. Out within the next few hours.

The ReC98 Shuusou Gyoku build is back running on Windows 98, with SDL 2 window creation and input! And what's this, even running in a window!? Yup, also restored general compatibility with D3DWindower. Still needs KernelEx and a SSE CPU though. That's for another push to fix…

Nevermind, Ember2528 will fully fund option 3 for netplay in the short term 💸 bsky.app/profile/rec9...

Which TH03 netplay option would you fund? (Please vote "port" if you can't financially contribute.) 1️⃣ Netplay-in-emulator 2️⃣ Netplay on PC-98 hardware 3️⃣ Port first / can't fund 📊 Show results

So, TH03 netplay. Recent funding developments have changed my original plan somewhat and placed it years into the future. Is there funding for getting it out earlier? A very important thread and vote 🧵

Looking forward to seeing libjxl get better at low-color images in the future!

github.com/nmlgc/rec98.... [💰] Confirm T0368 WishMakers joining with €50 toward translation support for Shuusou Gyoku! Thank you very much!

github.com/nmlgc/rec98.... [💰] Confirm T0366 €30 from an anonymous backer towards anything! Thank you.

github.com/nmlgc/rec98.... [💰] Confirm T0365 Ember2528 going up to €300 per month, and laying down a new long-term roadmap! • Better Shuusou Gyoku replays • TH03 decompilation • TH03 Anniversary Edition (one release) • TH03 replays • TH03 modern port • TH03 netplay 🙇🙏

🚚 The Shuusou Gyoku ReC98 build now runs on SDL 3! On Windows and Arch Linux at least. Flathub was kind enough to not immediately bully us into updating. Also, screenshot compression! Which is what the blog post is mostly about. Get it from GitHub, the AUR, or Flathub:

So I'm about to roast Arch Linux, SDL, QOI, JPEG XL, and lossy WebP in one 7,600-word blog post. We'll sure be eating good tonight. Out within the next few hours.

Build is out in all the usual places. Still working on the blog post, the content has exploded once again. It will have good math! bsky.app/profile/rec9...

Image compression always comes with a trade-off between file size and compression speed. The upcoming Shuusou Gyoku build comes with a built-in benchmark that lets you make an informed decision based on your system's performance. Here's what I get on a 7-year-old Intel Core i5:

Many thanks to this month's subscribers! The new Shuusou Gyoku build with SDL 3 and screenshot compression support will come out on April 3. Followed by the Windows 98 backport shortly after, and then lots of TH03 progress for the rest of April!

The menu image even triggers an unfortunate glitch in FJXL, JPEG XL's lossless encoder for -e1: > Runs hash-based palette detection > Sees this pixel with a color of #583732FF > Hashes to same value as #FFFFFFFF > Gives up palettizing and uses ill-suited photo filters instead