Shenmue (1999) reverse engineering reveals possible sun position oversight
85 comments
·March 12, 2025chiffre01
Playing through Shenmue 1, they did a really good job capturing the vibe of the area. Looking at random points in Yokosuka just feel like Shenmue.
https://www.google.com/maps/@35.2781594,139.677597,3a,75y,27...
dfxm12
Hasn't changed much since 1986, either. Speaking of Sega games set in Japan, the Yakuza games do a good job at this as well, at least for Kabukicho and Dotonbori. I even knew to get crabs at Kani Doraku because of the games! It's like virtual tourism in some ways...
pkdpic
Also playing through on Steam Deck. Steam QTE problems really haven't hindered my enjoyment at all. Kind of shocking how well it's aged overall and how different it is playing through as an adult.
I am waaay better at driving that forklift 20+ years later. The foreman loves me now.
drooopy
I replayed Shenmue on my Deck about a year ago and I had the same QTE problems. The solution was to download a custom, community-made control scheme from the Steam workshop.
jncfhnb
I too discovered that the forklift was in fact very easy as an adult. That was a shocker.
soupfordummies
Looks like a good spot to practice my moves...
If you google "Shenmue locations in real life" there's a lot of cool stuff. They really did do a great job on that and the ERA as well.
indrora
A friend of mine through sheer luck happened to be able to take a two month trip to Yokosuka nearly all expenses paid. She spent the first week or so just plotting out the map of Shenmue and the local map to see how much was rearranged.
The town is definitely Different but recognizable in a lot of ways. Lots of small landmarks that were gently adjusted or changed to make it simpler
pandemic_region
Is it typical for Japanese towns to have all the electricity wiring above ground? Is it on purpose, maybe related to historical earthquake trauma?
Daz1
Yes and also there is zero aesthetic thought put into japanese towns which is why they're so ugly, everything is functional
pezezin
I would say that functionality requires a minimum sense of aesthetics.
Most Japanese towns are not even functional, they are just a chaotic maze of tiny streets and ugly buildings. I know because I live in one.
lmm
> Is it typical for Japanese towns to have all the electricity wiring above ground?
Yes
> Is it on purpose
Yes? Electrical wiring is built deliberately, of course it's on purpose. Where else would you put it, and why? You're implying it's somehow normal to bury it? That sounds like it would be expensive, both to build and to maintain.
Cthulhu_
> You're implying it's somehow normal to bury it? That sounds like it would be expensive, both to build and to maintain.
It is in my neck of the woods (the Netherlands) too, the only places you see overground electricity is high tension lines outside of towns. Here's a random suburb I just picked randomly, looks like it was built in the 80's: https://maps.app.goo.gl/7DeZiTyKuB4DZKdG8. Or else Amsterdam, which is much older: https://maps.app.goo.gl/FWm6vYgbV5h2CkZu5.
I'd argue (based purely on gut feeling and handwaving) that having it out in the open is more expensive and dangerous; weathering, wind, trees, cars crashing into it, people climbing up into it, birds, etc.
Anyway, your comment sounds like US defaultism, be wary of that.
PinkMilkshake
> You're implying it's somehow normal to bury it? That sounds like it would be expensive, both to build and to maintain.
Yes, it's normal. It's called undergrounding.
wahnfrieden
You wrote condescendingly without even apparently knowing why
pretzelhands
I'm not sure about your location, but around here (Austria) it is indeed much more common to have electrical wiring that runs through the ground than above air. The only place where you see wiring above ground is usually out in the rural areas.
pezezin
Pretty much all Japanese cities look like that.
AdmiralAsshat
Reminds me of a similar story about Blast Corps, specifically how they implemented logic to correctly display apparent retrograde motion vis-a-vis the orbit of Venus from the perspective of Earth...all just for what basically amounts to a background animation. [0]
klysm
This is one of those things where it's like if you have to program them to move, it's probably just easiest to program it to be somewhat faithful instead of making up some other values.
pipes
Someone in the YouTube comments claims he was an intern at rare at the time and he was responsible for this. Who knows, they could be lying.
mywittyname
To me it feels like one of those escapades we go on when we want to focus on doing some "fun" work.
rawling
Isn't this just... they made the planets have the correct orbit times, and retrograde motion just drops out from that?
gs17
Yeah, it's impressive that they bothered to animate them with the correct ratio of periods, but it's not like they had to add epicycles.
QuercusMax
When I took the sophomore-level Computer Graphics class as an undergrad in 2001, the final project was to build a solar system simulator in OpenGL. It didn't have to be especially faithful (all orbits perfectly round, don't care about starting positions, etc). The most complicated part was implementing a view from a planet's surface which would rotate at the proper rate for the given planet. This was not a difficult assignment (for me, can't say anything about my classmates!).
Making it marginally more accurate for a real product would only have been a bit more effort.
antithesizer
Saty?
soupfordummies
Well that's ANOTHER oddball, semi-forgotten, great game!
toast0
Nintendo and Rare (as "Xbox Game Studios") figured out how to work together, and as of Feb 2024, you can play Blast Corps on the Nintendo Switch Online Expansion Pack (along with a bunch of other Rare games)
goosedragons
It's also on Xbox via Rare Replay. And you get to keep it.
TapamN
Shenmue is one of my favorite games. I did a bunch of Ghidra reversing on the Dreamcast version last year, since I wanted to add improvements to it. Like adding bilinear filtering on the sky background, making time run a bit (faster so you can see time specific events like Christmas/New Year more easily,) getting the game to run without disc swapping on an ODE, and adding antialiasing (which would require mipmaps to improve rendering performance, which would require higher texture compression levels to get them to fit, which would require a different texture format that supports that...) I never got around to actually implementing any of that, outside of doing some experiments, like forcing bilinear on all 2D elements.
I don't think I found the sun/moon code (or more likely I did, but didn't realize what exactly it was doing, Ghidra SH4 has serious problems with floating point instructions making following anything that uses them almost impossible) but I did find most of the other time related code for updating the clock/calendar.
One weird thing I found while doing that is about the in-game watch. You always have a watch in your inventory, so you'd think it would be hard coded in, but it's treated like any other item. The game also has code to check if the watch is missing and add it back in anyways. But the code that draws the on-screen clock also checks if you don't have the watch, and won't draw the clock if you don't have it (or at least part of the UI clock logic is disabled, I haven't actually tried seeing what happens if you don't have a watch to verify if my interpretation is correct).
On the PAL version, the code that checks for a missing watch is at 0x0c180dc6 (that's where the code is loaded into memory, subtract 0xc010000 to get the address in 1ST_READ.BIN), and I think the code for drawing the clock (or at maybe it was just updating the hands of the clock?) is at 0x0c18290a.
Dreamcast Shenmue has code to support other video modes, like alternate resolutions (320x240p!), antialiasing, and 24/32 bit color. They're a bit bugged, like when using antialiasing, the 2D elements being squashed into the left half of the screen, and some strange issue with the screen position for the RAMDAC being setting incorrectly, causing the screen to vibrate left/right by a pixel or two, but the 3D models were drawn correctly.
24-bit color worked surprisingly well (even if the flag intended to enable it didn't seem to work, and I had to force it elsewhere.) I would have thought that having less video RAM free would have caused serious problems, but the game just loaded fewer NPCs. It was strange playing without dithering.
ac2u
Is it true that lucky hit in Shenmue 2 used historical weather data so that humidity had an effect on the wooden pegs on the board?
makotech221
wouldn't using an emualtor allow you to do most of that stuff
TapamN
Some of it, but I'd rather use real hardware.
Ros2
The moon in-game also has a complex implementation. I don't think anyone realized this until the team porting the games to modern consoles pointed it out in an interview
https://www.phantomriverstone.com/2020/09/ryo-goes-to-moon-s...
regus
I was really hyped for Shenmue when it came out on the Dreamcast, but I wasn't crazy about it once I finally played it. It was a glorified point and click adventure game, and it ultimately had no ending or purpose. It was an interesting and ambitious idea for a game though, they threw the kitchen sink in there.
My favorite part of the game was playing space harrier in the arcade.
ascagnel_
While it's not a direct continuation, the Yakuza (and later Like a Dragon) series is a spiritual successor in some ways.
isthisfoss
I really hate this analogy. Yes it's also published by Sega but the director, development team, and gameplay elements are quite different. Shenmue to me was mainly about NPC interaction and open-world exploration whereas Yakuza is just a straight brawler re-intepreting classic Yakuza tropes.
The move from Shenmue I to Shenmue II almost makes me think that was the direction Yu Suzuki was heading but never really ended up there. Have not played Shenmue III yet so I could be wrong.
mtillman
I read every piece of US magazine coverage during the development of this game until finally 3-4 years later I bought my Dreamcast on launch and eventually Shenmue followed by a boot disc and Shenmue 2 (UK). 6 years of waiting to spend countless hours playing Space Harrier and Pachinko not to mention find some sailors. Absolutely loved this game.
ghostly_s
I’m not sure a single person in this thread actually read the article rather than just taking an opportunity to say how much they like the game.
I read it and I’m not sure I get the point—it seems in the end what they discovered is the simulated sun position in the first two games are based on each other's locations. Not familiar enough with the series to understand what implication that has, but in any case, is it an easter egg or an oversight? It can't be both.
denz88
The first game is set in Yokosuka, Japan, which has its latitude at 35deg north. The second game is set in Hong Kong, which has its latitude at 22deg north. It seems like whoever coded this data into the games may have swapped them.
nanna
Shenmue I and II will stay with me forever. I waited and waited for Shenmue III, and swore that when it came out I would buy whatever it took to play it, but the reviews were so poor that I haven't even tried it. Is it worth it?
dfxm12
Shenmue is in a unique genre. The gameplay of III is more of the same, but not very innovative on top of what came before it. So, if you like I & II, you'll probably like III. The game plays as if it came out in 2003, not 2019, if that makes sense, but it takes full advantage of the graphics capabilities of the PS4. I understand mixed reviews. If you did enjoy I & II, the gameplay feels nostalgic & familiar, and you've probably played nothing like it in the past 20+ years. If you didn't, the gameplay probably seems antiquated, if not quaint, and you understand why there aren't many games like it.
My qualms with the game were more story related.
ac2u
Haven't yet completed it. In my opinion, although the originals had a clunky control scheme, it still had charm. Really bugs me how they moved the camera to an "over one shoulder" view rather than directly behind like in the first games. (nitpick) They also changed the iconic font used in the for no good reason.
Rendello
I can't say from personal experience, but I did find this review by Dunkey hilarious and likely representative of the gameplay: https://www.youtube.com/watch?v=f7SVY9CyBBc
khaki54
Imagine being proud of yourself for 25 years, displaying "implemented innovative orbital positioning methodology for Shenmue" on your resume. It was even your promotion case for staff engineer since you did it yourself, and some guy comes by more than 2 decades later and points out that you actually did it wrong
pkdpic
I just coincidentally found my old dreamcast while cleaning out my dad's storage space... Guess I'll be buying some batteries for my VMU...
Also excellent write up and discovery, truly inspiring *clap_emoji *bow_emoji
qingcharles
My all-time favorite game. What's the best version to play these days?
pkdpic
Playing it on Steam Deck right now. Only issue is with QTEs but honestly hasn't bothered me at all. Thought that might ruin it. Overall it has been an excellent way to replay it so far.
billfruit
While not Shenmue, Yakuza:Like a Dragon: Infinite Wealth, released in 2024 has got good reviews.
Fantastic game!
The same development studio, Sega AM2, recently had a developer reveal that he had put an Easter egg into Fighters Megamix for Saturn. However, he mistakenly introduced a crash bug in it.
This set me off looking for the Easter egg. After a couple days of reverse engineering, I finally found it [0]! I love looking for this stuff.
[0] https://32bits.substack.com/p/bonus-fighters-megamix