[Mod] Gran Turismo 2 plus (bug fixes, restored content and new content) - beta 7 released

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You misunderstand. I assume the mentioned color is "Blue Orage" which pez most likely fixed as "Bleu Orage"
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Thanks for the quick reply and sorry if I didn't understand correctly. I'm using a translator and it's pretty rough.

So to summarize:

- Old color: "Blue orage

- New color: "Blue storm"

Right? (If so, sorry for the mistake, the translator was writing the opposite). By the way, on the line above it says "Bleu outremer" which is spelled correctly this time.
 
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Ahh yes, that's it.

Thanks for the clarification.

I can't wait to try it out and see what it's like. I'm not sure I understand why the EU version only weighs 27 MB while the JP and US versions are around 230/250 MB. Again, my apologies if this is already marked somewhere, I haven't had time to read everything yet. Just the demo 7 patchnote and the FAQ.

I think it's a shame not to be able to enlarge the garage. Quick question about that. (I don't know anything about coding or the game's architecture, so my question is probably silly, but I'll ask it anyway).

You say that enlarging the garage would have an impact on the data that's placed after it. Isn't it possible to move this data to the end of the code so as not to overwrite it when enlarging it ? (It's a hypothetical question, I suspect it would require a lot of extra work. The question is whether it's technically possible).
 
The EU version of the game is used as the base for the mod, because it's the latest release, with all the patches and bug fixes Polyphony did themselves. Since it's the latest, bringing those changes to the other regions means whanging a lot more files and data on them, therefore bigger patches.
As for the garage data, as far as i understand, this would require either to be done through hacks, like Silent's codes that use the 8mb dev ram mode on Duckstation, or by editing the game's source code, which we don't and likely will never have.
The critical data mentioned is that the game uses the "101st" car slot (in ram) to store the money, day counter, and owned car values, and those would need to be moved elsewhere in order to be able to use the spaces. I also believe from my own testing a long time ago, that the lists-type menus like the used cars and garage, are limited to 100 entries. After that, they won't scroll.
In the early 2010's i played around with using the "102nd" and "103rd" car slots, and successfully had cars on there, but i could'nt select them unless i changed the values of the driven car ID to them, because of said limit.
 
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Very interesting, thanks for your reply. It was surprisingly clear ^^

So if I understand correctly, it's possible, but very complex? And in any case limited to 103 slots?

I've just managed to patch the GT mode with this site: "https://kotcrab.github.io/xdelta-wasm/"

So I succeeded for the GT mode CD, which has the ".img" extension, but for the arcade mode, which has the ".mdf" extension (don't ask me why, I can't remember), no way. I'll see if I can find another one, otherwise I'll manage to make an iso of my original CD. Could it be a problem to use the GT CD patched with a basic arcade CD? I almost only play in GT mode anyway, but if it's going to break everything, I'd rather know anyway. ^^

Thanks again. :)
 
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Nah it's not possible, as we'll never have the source code to actually edit the position of the critical data in memory. I put those numbers in quotation (") because i used the space where those slots would be if they existed at all. They're not actually 102nd and 103rd slots. The ram has enough space to put at least 200 cars, provided the critical data could be moved. It's a bunch of empty space ready to be used other than that.
But even if we managed to use that space, the save data would need to be rewritten to save these additional slots as well, and whatever else that reads garage data, and that all would need to be done by editing the source code again.

Delta Patcher is the tool meant to be used to patch the game, but if the website you found does the job, i don't see why it would be bad. If you don't plan on using arcade mode, then you don't need to patch it. It's only if you would like to play on it that you'll need to.
Otherwise you can just play GT mode to your heart's content.
 
Thanks for all the information submaniac93. It's a bag of knots, basically...

In any case congratulations for this great work that I will test as soon as possible. I'm also going to modify my previous message so that everyone can access the site address to patch the game. You can put it on the topic's home page or in the FAQ if you like.

Thanks for all this information, and also for helping me get to bed feeling better than when I got up this morning ^^.

I'll leave you to it, I'll come back and give you a feedback once I've tested the game. Good night to you all. :)

P.S: Je viens de voir le drapeau Français à côté de ton nom. Ca aurais pu simplifier les choses... x)
(Or English is required here ?)
 
(Tout le monde parle anglais ici, c'est mieux en effet :P)
You're welcome, but i'm not the author of this mod haha. pez2k is the guy behind it, i'm only consulting and testing for it, it's all his work otherwise.
Though i doubt he'll add the link, as the rules on GTP are pretty strict. We'd rather stay in line when it comes to these things.

I have my own mod i'm working on however, but it's not releasing until at least a few years from now x)
 
Hello world.

(Ok alors i speakerai Anglais.)

Yes, that's what I thought I saw in the patchnote, but you still worked on it, so you deserve thanks too, although they're directed at all the people who participated in this project, near or far. (With pez2k at the top of the list, of course, for his wonderful work.) Your work on this mod may be less important, but without it, this mod might not exist, or not in this state. So I maintain.

I thought I'd also seen a mention of your mod. I'm also going to download it to try it out.
 
Just to confirm, yes, the Venturi fix was changing 'Blue' to 'Bleu', it's just not described very clearly in the changelog. I suspect it was just a typo in the game, since Bleu is spelled correctly for the other blue colour.

Also, Submaniac definitely deserves credit, he's contributed some great work to this mod, as well as tons and tons of vital research into how the game works.

I'm not sure I understand why the EU version only weighs 27 MB while the JP and US versions are around 230/250 MB.
...
You say that enlarging the garage would have an impact on the data that's placed after it. Isn't it possible to move this data to the end of the code so as not to overwrite it when enlarging it ?

27MB is basically the total size of the changes in the mod, most of what is on the disc is audio and video which I've not changed, while a whole new car can be as little as 50KB of data. The mod is built on the final re-release of both the JP and US versions of the game, and so the patches for older releases of the game include those changes, which are around 200MB for the JP version and 100-150MB for the US version. The JP and US versions of GT2 are also older than the EU version, so this mod updates them to use the same game data as the EU version, including the bug fixes that were in that version. This accounts for another 7MB or so for the JP version, and 100MB for the US version.

In short, the US v1.0 patch for example is made up of 150MB of changes from US v1.2, plus 100MB of changes from the EU version, then the actual mod data of about 27MB. The reason it's done this way is because lots of people own the older discs (especially the JP version), but the newer releases included critical bug fixes like fixing an issue that could delete all garage cars, so this mod is based on the newest versions. Using the EU data for all three regions also means that its bug fixes are included, and that I'm effectively only building one mod that can be applied to all regions, instead of three separate mods.

Regarding the garage data, the key point is that there isn't really anywhere to move the following data to. Even if it was possible to find somewhere to put it, and to change every place in the game that referred to that data, and to change every place in the game that assumes the garage holds 100 cars, then the same problem crops up two more times. There needs to be space for an entire second garage so that features like trading and the guest garage in Arcade can work, so all of the same work would need to be done again to handle that garage also being larger. Second, if it was possible to fit two larger garages in memory somehow, that garage data also needs to fit into the savegame. It would involve reverse-engineering everywhere in the game that reads and writes save files, then implementing a new save format with enough space for the larger garage, which would be totally incompatible with any other version of the game (and take up more blocks on a memory card). Even with the full source code of the game this would be a major effort to implement due to the number of changes required to critical parts of the game.

If all of that was somehow possible, then the whole thing needs to be done five more times, as there are two discs for each of the three regions that would all need their own patches. It could even be more than that, as each of those six discs has seven different executables on it.
 
Hello everyone.

Thank you very much "pez2k" for this very clear and well explained explanation.

I understand better the size difference. In fact it comes from PD updates to align with the EU version and the weight of the mode. On the other hand, I was really surprised to learn that a car doesn't weigh more than 50kb, I was expecting much more. But it's true that after thinking about it and reading your message, given the quality and resolution of my textures, it's clear that the heaviest weight comes from sound and video. (I've always wondered how to save a game from a 700 MB (or more) CD to a 1 MB card, but this explains it).

I'd heard about this garage suppression problem on the first JP version. It seems to me that it's due to the fact that originally you could record 10 best times on the 400M, 1000M and max speed events, then probably due to lack of space, they revised this figure downwards and went to 8 possible entries. But they forgot or incorrectly deleted the two extra entries, and when a record was broken, the ninth successful attempt recorded the record data on a critical part of the garage memory location. Or something like that.

It just goes to show how sensitive garage data really is, if even PD manages to create this kind of bug by simply forgetting one piece of data.

And I suspected it was a colossal amount of work, but what I imagined was nothing compared to what you described in your message. (I've understood everything by the way, I understand better how a Play game works, thank you very much).

I just didn't understand why they put 7 executable per version of the game?

I'm also wondering if the bonus CD that came with the "special" version of the game (the one that included the B license and 100,000 credits) is compatible with your game? (I don't have it anymore, but it's always good to know. ^^)

#jétoukompri
 
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Aaah and I also have another question about GT2, because for me there's always been a big mystery in this game.


I've always wondered what was going through PD's mind to propose a VMAX test on an oval track, instead of a 10 or 20 KM long flat straight line ? (Besides, you can only do one lap (except if you take the track upside down) and sometimes it's really limiting for some cars, either because it's hard to take an absolutely perfect trajectory in the corners or because the distance is too short).

Is it possible (again, this is a technical question, not really a request to modify the game) to do another VMAX test by coding just a 10 or 20 KM long straight line ?
 
I just didn't understand why they put 7 executable per version of the game?
...
I'm also wondering if the bonus CD that came with the "special" version of the game (the one that included the B license and 100,000 credits) is compatible with your game?

Each different 'mode' in the game has its own separate code overlay, for example the main menu, replay mode, the GT mode menus, the pre-race menus, and so on. I presume they must have run into problems fitting all of the code into memory, hence why it swaps out a big chunk for each mode. GT1 does the same thing, but in a simpler way, and I believe GT3 and GT4 do too.

The save on the French bonus disc won't work with the mod in the same way that any old savegame won't, but I have considered doing a GT2+ patch for it in the past, with a version of the savegame updated to work with the mod (and an English option). It's never been a high priority though because it's a very obscure release and realistically nobody is going to use that save nowadays.

I've always wondered what was going through PD's mind to propose a VMAX test on an oval track, instead of a 10 or 20 KM long flat straight line ?
...
Is it possible (again, this is a technical question, not really a request to modify the game) to do another VMAX test by coding just a 10 or 20 KM long straight line ?

The Test Course oval is heavily inspired by the Yatabe oval in Japan, which was popular in the 90s for doing speed tests in highly tuned cars. I believe the tests ran more or less how the top speed test in GT2 works - a full lap with a speed trap at the end.

It's not possible to modify or create tracks currently, so a straight line course can't be made. The game would also likely struggle with a course of that length (even Pikes Peak is cut down to 4.2km), and I suspect the car physics would break before reaching the end of it. In racing games, the further a vehicle gets from the centre point of the world, the harder it gets for the game to handle the increasingly large coordinate values, and at some point it breaks things. The Nurburgring alone can be a struggle for some games, with parts of the track as much as 5km away from the centre. Trying to get a PS1 game to handle 10km of distance is probably unlikely to work.
 
Thank you very much for this historical and technical point.

It's really interesting, I love knowing how games and consoles work from the inside.

When you say "physics breaks down", what does that mean? You're driving along and PAF your car explodes into millions of polygons ? (That must be funny, I'll try to get out of a map and test that. ^^)

I imagined it was a technical limitation, but I didn't know that speed tests were practiced like that in Japan. That explains why they kept this circuit for the following opuses. Or perhaps because of technical problems too. If you say that with the Nurb on GT4, it's already limited. It's true that it's prodigious for the time to have released a 20km circuit without loading, and quite well reproduced. (Well, I guess, I've never been on the real thing).

I didn't know about this physics destruction problem either. It's a bit like the "end of the world" problem in Minecraft, where after a certain distance, the terrain is no longer coherent at all and starts to be just a bunch of randomly aligned blocks with no coherence whatsoever. But I'm not sure if it's the same thing, since you say it's specific to car games. In any case, that's what it looks like in my mind.

Thanks again for all these clarifications, I hope I won't bother you too much or delay you in your projects with all my questions.

Good night everyone. :)
 
It's a bit like the "end of the world" problem in Minecraft, where after a certain distance, the terrain is no longer coherent at all and starts to be just a bunch of randomly aligned blocks with no coherence whatsoever. But I'm not sure if it's the same thing, since you say it's specific to car games. In any case, that's what it looks like in my mind.

Yep, it's exactly the same issue - I just couldn't think of any non-racing games that allow the player to move that far away!

Don't worry about asking questions either, I'm happy to answer them.
 
Well, there's that one. ^^

That's nice, I won't hesitate to ask if I have any other questions then. Thank you.

I haven't had time to test the game yet, but I'm really looking forward to it.
 
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@pez2k
Thanks to @TeaKanji I have become interested in how tuning works in GT2. So far the only cars I managed to achieve good progress in tuning were 4WD cars. Now the issue with tuning lies with some cars you have converted to rear wheel drive like the R33 LM Road Going Version. The car reacts like an FR on launch however beyond that you're driving a 4WD car. You can notice how all 4 wheels are rotating in the same speed in replays + my tune for the R32 RM works perfectly with the car.
Do you know about this physics issue? Also I have yet to test the R33 & R34 GT500s to see if they suffer the same issue.
 
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Now the issue with tuning lies with some cars you have converted to rear wheel drive like the R33 LM Road Going Version. The car reacts like an FR on launch however beyond that you're driving a 4WD car.

I haven't touched the physics for the R33 LM, it's using the same FR drivetrain it always has, the same one as every other FR car. It's only the GT500 cars and the 280MR that had the wrong drivetrain, and they're now using the same settings as GT3's R34 GT500 and GT2's GTS25t respectively.
 
I haven't touched the physics for the R33 LM, it's using the same FR drivetrain it always has, the same one as every other FR car. It's only the GT500 cars and the 280MR that had the wrong drivetrain, and they're now using the same settings as GT3's R34 GT500 and GT2's GTS25t respectively.
Oh wow. Well that was stupid of me. Though I still can't fathom how it handles & drives like a 4WD. The physics of GT2 are an enigma.
Edit: Having tested cars like the Honda S2000, Supras & Mazdas, all of them drive as you'd expect from a FR car (i.e being tail happy) except the R33 LM where understeer is prominent & there's no snap oversteer.
 
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Hi everyone.

@pez2k:

On the subject of GT500s, I also had a question. I don't know if what I'm about to say is a fact, or just an impression, but it seemed to me that all these cars had slight differences in behavior. I don't really know how to describe it, it's more a matter of how it feels when I'm driving. But if you use the same basic model for all the GT500s, these differences (if they exist) will be lost, right ?

@Oreca 1998:

Skylines in the real world have a special system that calculates the car's parameters 100 times a second and distributes power to the wheels that need it.

So it's a 4WD, but at times and according to need, it can also behave like an FR or maybe even an FF.

Now, I don't know whether such a complex system has been recreated in the game, or whether they've made a less efficient adaptation because of technical limitations, or whether they've removed it.

But maybe that would explain why, at start, you have the impression that the car behaves like a FR, no ?
 
@Oreca 1998:

Skylines in the real world have a special system that calculates the car's parameters 100 times a second and distributes power to the wheels that need it.
Yes. I believe it's called ATTESA.
So it's a 4WD, but at times and according to need, it can also behave like an FR or maybe even an FF.
Now, I don't know whether such a complex system has been recreated in the game, or whether they've made a less efficient adaptation because of technical limitations, or whether they've removed it.
I'm leaning more towards the latter as the car launches like an FR but drives like a 4WD loosely simulating the ATTESA system.
 
On the subject of GT500s, I also had a question. I don't know if what I'm about to say is a fact, or just an impression, but it seemed to me that all these cars had slight differences in behavior. I don't really know how to describe it, it's more a matter of how it feels when I'm driving. But if you use the same basic model for all the GT500s, these differences (if they exist) will be lost, right ?
...
So it's a 4WD, but at times and according to need, it can also behave like an FR or maybe even an FF.

Now, I don't know whether such a complex system has been recreated in the game, or whether they've made a less efficient adaptation because of technical limitations, or whether they've removed it.

All of the '99 GT500 Skylines are the same in terms of physics, with the two '97 cars being almost identical too. Applying the RWD setup from GT3 was mainly just some minor adjustments to the suspension and LSD, settings which were already identical across all of them.

As for the GT-R 4WD system (named ATTESSA, as mentioned above), GT does have a special AWD mode that does a very basic simulation of it, but the GT-R LM isn't AWD at all, it's set up as simple FR. It's exactly the same drivetrain setup as something like a Silvia or Viper, FR and nothing more. If the LM was 4WD / AWD in any way, it would show up as 4WD in the garage, and it doesn't, because it's FR.
 
@pez2k
Then it must a physics thing.
This tune for the R32 GT-R worked perfectly with the R33 LM
I usually set the dampers to 4 on front bound & rebound, and 6 on the rear for FR cars which I feel leads to better handling for FR cars.
Then again setting up the suspension is down to preference.
 

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So if I understand correctly, the differences between the different models are in my head ? ^^

Indeed, I had checked when I read the patchnote, and indeed the GT500 since 1994 are all FR because the ATTESSA system approached a too big advantage in racing. And it seems to me that the GTR-LM is sold as an FR in reality too.

What do you mean by "some differences in suspension and self-locking" ? These are differences you've added, aren't they ? The translator makes me doubt the turn of phrase.

It's interesting that they tried to adapt the ATTESSA too. Is it really only at the start that it's in FR ? Sometimes I get the impression that it switches back to FR when drifting at a very steep angle. But again, it's more an impression than an actual fact. I don't know what the data says about this.

As for settings, as far as I'm concerned, I adjust according to the track I'm on. On circuits with fewer corners and fairly flat, I go up to 10 on the rear and 8 on the front. On the other hand, on more winding tracks with a bit of relief, like "Trial Mountain" or "Laguna Seca", I loosen up a little and raise the ground clearance.

I also play with the aero, because I've noticed that people often leave all the values at full (to optimize handling), but I've noticed that on circuits like "Apricot Hill", "Test circuit" or circuits with long, not too tight turns, you gain in VMAX without it becoming really annoying in terms of handling.

EDIT: By the way, I'm sorry if I sometimes misunderstand or express myself badly. I use a translator who sometimes makes a mess of things. (Like changing what I write to something that doesn't mean the same thing at all, or changing turns of phrase). Which has a slight tendency to annoy me ^^.
 
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So if I understand correctly, the differences between the different models are in my head ? ^^
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It's interesting that they tried to adapt the ATTESSA too. Is it really only at the start that it's in FR ? Sometimes I get the impression that it switches back to FR when drifting at a very steep angle. But again, it's more an impression than an actual fact. I don't know what the data says about this.

Yes, as far as I've seen there are no differences in the physics data and car setups.

Regarding ATTESSA, I have no idea what the game does to try to simulate it, but I think the real-world system runs as FR until it detects wheel slip or a certain level of lateral G-force, then moves drive forwards to help increase traction and grip. It's not actually very advanced by modern standards, but it was marketed well back in the early 90s so Polyphony will have viewed it as a really cutting-edge system at the time.
 
Ok, so I'll check my settings, maybe it's me who didn't set them all the same.

From what I've read, the ATTESSA system works well the way you describe it. I don't know about today, but at the time it was revolutionary. It was one of the (or maybe even the) first mass-produced car to have an active electronic system that could modify traction (and maybe suspension, but not sure) in real time. (It was totally crazy in the early 2000s, at least for a European who didn't even have smartphones back then. 2000 for us Europeans, because that's when the Skyline became popular in Europe, but in Japan they've had it since the 80s. Which is even crazier).

And unless I'm mistaken, such a system didn't arrive (still on mass-produced vehicles) until 10 or 15 years later with other manufacturers. And even then, it's often confined to luxury or fairly high-end cars.

I think Nissan was a real pioneer in this field, and paved the way for active electronic control on mass-produced vehicles.

I've always liked the Skyline(s), it's a really excellent car, very permissive and fun to drive. It's one of my favorite cars for having offered so many revolutions and so much performance at such a low price compared with the others manufacturers at the time (of course, prices are not the same now).

On the other hand, while I love it on video games, it seems that in reality, despite its low purchase price. It's a complex car that's quite expensive to maintain. (Unfortunately, I haven't been able to verify this for myself yet. Maybe one day. ^^)

Edit: I also heard something that surprised me at the time. In the R34, it seems that you can play Gran Turismo 4 in the car, which includes a PS2, make settings on the game, and transfer them to the car.

However, I've never seen a demonstration of this system, so I don't know if it's true.


Good night everyone. :)
 
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I don't know about today, but at the time it was revolutionary. It was one of the (or maybe even the) first mass-produced car to have an active electronic system that could modify traction (and maybe suspension, but not sure) in real time. And unless I'm mistaken, such a system didn't arrive (still on mass-produced vehicles) until 10 or 15 years later with other manufacturers.
You should read about the 1987 Subaru XT/Alcyone (predecessor of the SVX/Alcyone found in the game). That had electronic AWD and adjustable suspension.

And even then, it's often confined to luxury or fairly high-end cars.
So you don't consider the Skyline to be a luxury and/or high-end car?

Note: ATTESA only has one 's' - Advanced Total Traction Engineering System for All-Terrain
 
Regarding ATTESSA, I have no idea what the game does to try to simulate it, but I think the real-world system runs as FR until it detects wheel slip or a certain level of lateral G-force, then moves drive forwards to help increase traction and grip.
Supposedly, the R34 had a more advanced "Pro" version of ATTESA that also allowed left/right torque transfer at the rear wheels, like the Evo GSR IV+'s Active Yaw Controller. The game doesn't allow an AYC on the R34 though. so I'm guessing that part isn't modeled.

Speaking of Yaw Control, I'm trying to figure out why the 99 Prelude Type S (SH in North America) allows you to install an AYC, but then gives you no control over it (setting is stuck at 1). And I would think that the Mugen Type S would allow you to install an AYC, but it doesn't? Bug(s)?
 
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