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

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Bug report - the exhaust tips on the E55 AMG are body-colored and change their color when one changes the color of the car. Although I think this issue was in vanilla, as well.
 
Bug report - the exhaust tips on the E55 AMG are body-colored and change their color when one changes the color of the car. Although I think this issue was in vanilla, as well.

Yeah, it's not as noticeable in vanilla due to the lack of colours overall. I've had a look at it before, and unlike other cars with similar issues there's not a lot of free space in other palettes to reuse.
 
As for the R390 the longtail road car supposedly has over 500 horsepower and can go 220 mph. Then again I don't know if that thing still even exists. As far as gearing goes maybe just fudge the numbers.


it still exists and was recently in the US.
The short tailed red car doesn't.

It's never been road tested though so acceleration numbers and horsepower are up to interpretation.
 
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The red car was rebuilt with slightly different body parts in order to be similar to the 98 Race car and was repainted blue. They (the red and the blue versions) are basically the same car.
 
The red car was rebuilt with slightly different body parts in order to be similar to the 98 Race car and was repainted blue. They (the red and the blue versions) are basically the same car.
How many games besides GT2 even feature the '97 short tail R390? I know one of the Forza titles had the short tail race car. For that matter, how many other games even feature the road spec? The '98 race car definitely seems to appear in plenty of games.
 
How many games besides GT2 even feature the '97 short tail R390? I know one of the Forza titles had the short tail race car. For that matter, how many other games even feature the road spec? The '98 race car definitely seems to appear in plenty of games.
Forza Motorsport 3 had the 1997 Short Tail Race Car, which Turn 10 got rid of for the 1998 car for some reason. Despite the fact the 1998 R390 GT1 Race Car in FM1-4 was basically the 1997 body with a 1998 livery. 2 other games that I know have the R390 1997 licensed are Race Driver: GRID and Over Drivin' Skyline Memorial. Over Drivin' Skyline Memorial was basically a special, Japanese Version of Need for Speed that tributed to Skylines.


Oh and The Real Car Simulator R: Nissan Edition:
rcs2.jpg


It was also in some other games non-licensed: http://www.igcd.net/search.php?title=nissan+r390
 
I'm running GT2 plus on a Retroid Pocket 3+ (android) through Duckstation. The 60fps cheat seems to break the game on Simulation, but runs fine on arcade mode. In fact the game runs beautiful at 60 fps and upscaled (if I overclock the cpu), but I get a forcefield pushing all cars off the track and most cars cause the game to artifact/crash on the car selection screen. (regardless of the overclock, it's once the 60fps cheat is on)

Is this a common/fixed issue? I'm having trouble finding anyone with some knowledge, this seems to be the hub. Is there or will there be any GT2 related discords?
Thanks
 
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Here's another little change that I didn't think would be possible just a couple of weeks ago - tweaking the power units in the game. The original JP version uses metric horsepower (PS), and so all of the game data is set up in PS too. The US and PAL versions however convert to Imperial horsepower (almost) everywhere they display power, which leads to a lot of weird values. It also means that the game technically has the wrong units in French, German, Italian, and Spanish, as those countries all use metric horsepower like Japan does. The pre-race car setup menu also displays metric in all regions, as it was missed out when the conversion was added in.

To fix most of that, I've patched the PAL version to use metric horsepower, which is accurate for four of the languages on the disc, much better than just one as it was before. It also tidies up a lot of things:

First, the displayed power numbers for cars are now the nice, rounded figures that the manufacturers advertise, rather than weird numbers like 147hp or 276hp:
metric-power.png


Most importantly, the race restrictions are now shown as the easily remembered round values that they were intended to be. Much easier to pick and tune cars to stay below 600hp than to try to recall whether the limit was 591hp or 592hp:
metric-races.png


Finally, the power displayed in the garage in both GT and Arcade modes now matches the power shown in the pre-race menus, eliminating the ancient myth that cars could be tuned higher if the player waited to equip new parts until starting a race:
metric-escudo.png

metric-escudo2.png


This doesn't affect the performance of cars, nor which cars are eligible for events, as these are the actual values that the game has been using all along, they're just no longer disguised by a unit conversion when displayed.

Currently this change is just for the PAL version, but I'm considering doing it to the US version too. Technically metric horsepower is the wrong unit for that localisation, but the advantages are that it would clean up the race restrictions and resolve the pre-race power difference, as it does for PAL.



I'm running GT2 plus on a Retroid Pocket 3+ (android) through Duckstation. The 60fps cheat seems to break the game on Simulation, but runs fine on arcade mode.

You're probably better off asking the emulator developers or the authors of the 60fps code. I can't really provide support for emulators or other people's mods.
 
For the sake of consistency I'd say show the values in metric horsepower for the US version too.

Yeah, I think that's probably reasonable. Assuming that the related code wasn't changed between the US and PAL builds, it should hopefully be more or less the same patches needed too (patches plural - the calculation is done in lots of places, hopefully just because the compiler inlined it and not because someone at PD copied and pasted it everywhere!).

have you guys seen the ferrari mods?

They have their own thread, nothing to do with GT2+.
 
One more breakthrough, which I never expected to accomplish - fixing the inability to unequip intercoolers from the Vector W8.

In the pre-race Change Parts menu, the game checks whether the current car has NA Tune upgrades (to show or hide that item in the Engine menu), and checks whether it has Turbo Kit upgrades (to show or hide the entire Turbo section). The Vector W8 has intercooler upgrades, but no turbo upgrades, so the whole section is hidden.

The check deliberately skips the stock 'stage 0' turbo kit, because all cars have a stock turbo kit. NA cars all use a shared 'no turbo' part with zero boost and zero power, so when the code checks if there are any turbo kit parts for the current car, it would always find the stock one unless it was skipped. However, the 'no turbo' part is always part ID 0, so it just needed two instructions to be patched to start the check from stage 0 instead of stage 1, and ignore both invalid (-1) and part ID 0, instead of just invalid.

This means that the menu shows up for the W8 despite having no turbo upgrades, as it's a turbo car stock:
w8parts.png


And, finally, because the menu shows up, the intercoolers can be equipped and unequipped at last:
w8parts2.png


This also makes the Turbo section show up for any turbo racecars and concept cars - they don't have any upgrades but the game already showed all of the other sections that have none too.

There was a workaround hack for this issue in earlier versions of the mod, which I can now remove in favour of fixing the code directly. I've been looking for a solution to this problem for at least 4 years, so I'm over the moon that I suddenly stumbled across the fix after working on the metric horsepower patch. It crosses another previously unsolvable bug off the list, one step closer to the goal.
 
Forza Motorsport 3 had the 1997 Short Tail Race Car, which Turn 10 got rid of for the 1998 car for some reason. Despite the fact the 1998 R390 GT1 Race Car in FM1-4 was basically the 1997 body with a 1998 livery. 2 other games that I know have the R390 1997 licensed are Race Driver: GRID and Over Drivin' Skyline Memorial. Over Drivin' Skyline Memorial was basically a special, Japanese Version of Need for Speed that tributed to Skylines.


Oh and The Real Car Simulator R: Nissan Edition:
rcs2.jpg


It was also in some other games non-licensed: http://www.igcd.net/search.php?title=nissan+r390

where do you get the nissan edition of TRCS-R? i want specifically that edition, and i cant find it anywhere, i figured id find it on archive or myabandonware but no luck, this game isnt being sold officially still is it? i really dont want to pay over 200 for a boxed copy of the toyota edition either lol - Edit: sorry to get off topic
 
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where do you get the nissan edition of TRCS-R? i want specifically that edition, and i cant find it anywhere, i figured id find it on archive or myabandonware but no luck, this game isnt being sold officially still is it? i really dont want to pay over 200 for a boxed copy of the toyota edition either lol - Edit: sorry to get off topic
Unfortunately, I can't tell you that. I only know the game exists thanks to IGCD, it's a more obscure game, so it not being published on those sites is not a surprise. As it's an old game, you're probably going to have to search ebay or maybe an imported gaming site for it.
 
Unfortunately, I can't tell you that. I only know the game exists thanks to IGCD, it's a more obscure game, so it not being published on those sites is not a surprise. As it's an old game, you're probably going to have to search ebay or maybe an imported gaming site for it.
I ended up finding it online, not too shabby of a sim, a little oversteery if you will, but still very interesting
 
would a source port/engine recreation of GT2 ever be possible? I know that this may not be the right place to ask but it seems like endevours like this are kind of in vein sometimes due to the limitations of GT2's simulation disc, id love to see a reverse-engineering or maybe even an open source physics engine, that allowed for a similar career mode to gran turismo mode to be played, im honestly kind of surprised nothing of the sort has been done before now
 
would a source port/engine recreation of GT2 ever be possible?

There is no source code for GT2 available, and there are no debug symbols to help with decompiling it. I don't have the skills for it either. It can't even be recreated from scratch, as a lot of the file formats are unknown and thus would not be loadable.
 
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The alternative would be to remake everything with another engine, although that would probably be DMCA`d by Sony.
 
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A bit more development that has been done lately - sorting out the Weds Sport Celica. Submaniac had noted a while back that the car was way too heavy, so I went looking for actual numbers. He found an old JGTC game that listed some data, then along with ddm we found that the original JGTC website from 2001 had a pretty good overview of the 2000 season cars, as well as the technical regulations dealing with car minimum weights. It turns out that the Celica was a naturally aspirated car, and thus could run at a very light weight. Unfortunately, in GT2 it has a turbo engine and the weight of the GT-Four road car, so very much wrong on all levels. I try to avoid inventing data where possible, but since Polyphony's original engine data was entirely fictional, I set up a new fictional torque curve which at least hits the same peaks as the real-world data.

The showroom stats, before and after:
weds-before-1.png

weds-after-1.png


The actual engine specs - despite the loss of the huge low-end torque and dropping it to the real level of power, the weight reduction means it's just as fast in a straight line:
weds-before-2.png

weds-after-2.png


Of course, GT2's race cars all have big power boosts compared to the real thing, so after this I added a 115% power multiplier to put the Celica somewhere around the pace of the FTO. I also fixed the weight of the Tsuchiya MR2, but it turns out that (assuming 1999 had the same weight rules as 2001) all of the GT300 cars in GT2 are running way, way underweight, so the MR2 at real weight is still a bit heavy. Don't know if I'll go through and change them all without direct confirmation that the rules were the same though.


I've also finally spent the time to go through and revamp the hardcoded bits of localised text used for the tuning menus. It looks like Polyphony gave their translators the word 'Nothing' instead of 'not available' for parts that the current car doesn't have, and 'Already' instead of 'purchased' for parts that have already been bought, so the translated text often makes little sense. With the help of native speakers like Submaniac, SuperFrizzio, and Paiky, the mod now has much more natural language used in these places, as well as fixing some damaged text in non-English languages caused by the font not supporting accents and umlauts.

localisation.png



The alternative would be to remake everything with another engine using the same model data, although that would probably be DMCA`d by Sony.

As my earlier post, many of the file formats are not known well enough to be able to load them in a different engine. Nobody's even managed to rip a complete track from the game, never mind fully document the format to write a loader and reproduce all of the quirks.
 
Is there going to be a newer version of the mod with all the recent fixes and updates?

No, I'm keeping it all for myself.

Only joking - yeah, of course there will be a beta 7 release before too long, but I have a lot of things to polish and finish reworking first. I was generally quite busy last year, so I'm catching up on a lot of things that are now possible to fix or tweak, in order to get a nice chunky changelog.
 
As my earlier post, many of the file formats are not known well enough to be able to load them in a different engine.
For some reason I was thinking it was simply the GT1 track data. I edited that now..
 
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Is it possible to adjust the power levels of the rally and JGTC cars to better reflect their real-world counterparts?

AFAIK the rally cars usually made 300 hp at 5500 to 6000 rpm
 
Here's another dump of a lot of little things that I've been ticking off the infinite to-do list, one by one.

I took another look at the exhaust on the E55 AMG which is painted body colour, and unlike 4 years ago it's actually now a trivial fix with modern tools, so I sorted it out. It looks like it was mistakenly marked as recolourable, so when PD made the other paint colours from the silver base, it was tinted to match. While I was at it, I decided to fix the squashed night headlights too:
e55lights.gif


I also did a pass through all of the JGTC GT300 cars, as nearly all of them have the road car's headlights pasted onto them at night rather than using the actual lights fitted to the racecars. This meant removing the popups on the Momo MR2, and illuminating the little spotlights in the headlight covers for the others:
wedscelica-lights.png

daishin.png


The three models of Suzuki Wagon R have quite different bodykits stock, but when race modified all three of them get the slatted Aero RS grille. Now, I've copied over the grille designs from the original cars to the RMs for a bit of variety, with my favourite being from the '97 base model:
wagonr-ft-rm.png


One of the bigger jobs recently was revising the Nissan 200SX '95 - unlike virtually every other regional rebrand in the game, the '95 and '98 200SX are actually separate cars to the equivalent Silvia K's, and modified to look like UK models. The '98 is spot on, with the correct front and rear bumpers and side indicators, however the '95 has the front end from a Silvia K's with the optional Navan bodykit. The 200SX had a less aggressive kit, with standard-fit foglights for a bit of premium trim. I've reworked the bumper entirely to look more like a UK car - it's not perfect due to the low-poly model, but it's better than being totally wrong. Here's a before and after of a Navan-kitted Silvia K's and a 200SX:
early200sx-before.png

early200sx-final.png


Now it's a noticeably unique car, as it should be:
200sx-replay.png


I also spotted however that the 200SXes were carbon copies of the Silvia in terms of physics, so now they're proper EU spec with about 10% less power, a bit more weight, and longer gearing for autobahn cruising:
200sx-stats.png


Something on my long-term list has been to go through Arcade mode and replace the completely inaccurate displayed stats for the fictional rally cars with something closer to the performance that they actually have. For a lot of cars this is a 70-100hp jump, and less weight than they previously claimed. The physics haven't changed, but now the menus don't lie:
evo4-arc.png

saxo-arc.png


One more, and this is a tiny one, entering a license in UK English no longer claims that your launch speed is in mph:
license-kmh.png


This isn't everything either, there have been other little fixes such as painting the missing exhaust back onto the Legnum Super VR-4 which are too minor or boring to show off, but work towards eliminating all of the known issues.


Is it possible to adjust the power levels of the rally and JGTC cars to better reflect their real-world counterparts?

It's possible, but the problem is that it's not just one figure to change from 460 to 300. The whole torque curve for each car would need to be remade, and in general it's not possible to find data on how the real torque curve would look, and it's something that would require all of them to be changed for consistency and balance. Polyphony seem to have sort of made up what they think the racecars would perform like without air restrictors, and gone with that. The later games do the same, so I can't even backport the data from them.
 
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I think i may have just realized that ive never actually played this mod, and i have been patching my simulation disc 1.2 wrong, i recently re read the additions in the complete edition, and saw that the RUF lineup was update with 4 new cars, yet i cannot find these cars in the dealership, do they perhaps cycle cars as days go by? maybe thats why I cannot seem to find these cars? or are they prize cars perhaps? tbh i never really knew how to even tell if my bin file was even actually patched or not, if i did this wrong, ill try it again with a fresh image and see if i cant get some help figuring out what i may be missing if i cant get it to work.
The RUFs are prize cars for now, on the next version they should be available in the dealership.
To see if your game is patched check if you have both Opel and Vauxhall dealers since in the original game it's either one of them, depending on what region of the game you have.
 
The RUFs are prize cars for now, on the next version they should be available in the dealership.
To see if your game is patched check if you have both Opel and Vauxhall dealers since in the original game it's either one of them, depending on what region of the game you have.
thanks for clearing this up, i also wanna apologize for how often i open this thread, i just love this idea so much, and gran turismo 2, i think pez2k is really doing great work in picking up where polyphony had left off due to time constraints and i cant be more thankful!
Edit: i have these dealers as well!
 
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A few more changes I've been working on for beta 7:

I've always been curious as to why there are two Ruf BTRs in GT2 (labelled Type I and Type II), and after taking a proper look at them, it turns out that the Type II actually makes 400hp rather than the advertised 374hp like the Type I. This seems to suggest that they're meant to reflect the original 374hp BTR spec, and the later, more powerful BTR II revision (with the even later BTR III making 408hp). However, the Type I has the newer CTR style bodywork, and the Type II has the older 934-style bodywork like the 374hp BTR in GT4. I've now swapped them around, so that the early car matches GT4, the newer car is the more powerful spec, and then updated the menus and stats to match. The hardest part by far was removing the old text from the menus!
btrswap.png

btrii.png


Another job I've been pushing along with is to revert the remaining 'localised' names for the Japanese cars in the Complete version. I've gone through Daihatsu, and Mazda too:
mazdadealer.png


The used dealer at Mazda is also a bit more interesting now, with their various sub-brands showing up:
mazdaused.png


Finally, MMRivit made a huge donation of a full set of manufacturer event screens with the names changed to match, which has saved me a ton of time and effort. They look spotlessly great too:
nissanevents.png


Not everything is easy to show off in a screenshot, so as usual there's even more than the above - fixing the turbo and NA events showing the wrong error message when trying to enter in a car that doesn't meet the requirements, fixing the weird message when trying to change the wheels on a BMW in the US version (in vanilla and Light), changing the Japanese version to require the IA license for the Muscle Car Cup like other regions, and more. The changelog alone is going to take me a while to write!


To see if your game is patched check if you have both Opel and Vauxhall dealers since in the original game it's either one of them, depending on what region of the game you have.

I don't know if I've previously announced it, but there'll be a simple way to check if the patch has been applied in the next version, as the above only works on the Complete version. Currently in Light, the easiest check is to see if the Audi S4 costs more than the basic A4, which needs the user to know that was originally broken.
 

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