Gran Turismo 4 Modding Discussion

I assume it's different to GT3? Someone has been adding cars from GT4 variants into GT3
To my knowledge this is possible because GT4 Prologue, GT Concept and all other demos (Prius edition etc.) use the same game engine as GT3. GT4 uses a different engine so, for now at least, porting cars is not possible.


A question for @TheAdmiester. It is possible to change in which dealership cars are sold? Theese are some of the oddities i spotted and where I would place them:

Chevrolet Corvette C5R in new dealership
Panoz Esperante in classics dealership
Buick Special in tuner village or "full model" in tune shop
Eagle Taloon in classics dealership
Aston Martin DB7 in classics dealership
Jay Leno Tank Car in new dealership
Bentley Speed 8 in new dealership
Lotus esprit GT350 in classics dealership
Citroën Xantia in classics dealership
Citroën Xsara Kit Car in classics dealership
Audi R8 LMP in new dealership
BMW Mclaren F1 GTR in classics dealership
Hyundai Tiburon Turbulence '99 in classics dealership
Honda Gathers Drider Civic in classic dealership
Subaru Impreza 22B Rally Car in classics dealership
 
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To my knowledge this is possible because GT4 Prologue, GT Concept and all other demos (Prius edition etc.) use the same game engine as GT3. GT4 uses a different engine so, for now at least, porting cars is not possible.


A question for @TheAdmiester. It is possible to change in which dealership cars are sold? Theese are some of the oddities i spotted and where I would place them:

Chevrolet Corvette C5R in new dealership
Panoz Esperante in classics dealership
Buick Special in tuner village or "full model" in tune shop
Eagle Taloon in classics dealership
Aston Martin DB7 in classics dealership
Jay Leno Tank Car in new dealership
Bentley Speed 8 in new dealership
Lotus esprit GT350 in classics dealership
Citroën Xantia in classics dealership
Citroën Xsara Kit Car in classics dealership
Audi R8 LMP in new dealership
BMW Mclaren F1 GTR in classics dealership
Hyundai Tiburon Turbulence '99 in classics dealership
Honda Gathers Drider Civic in classic dealership
Subaru Impreza 22B Rally Car in classics dealership
It is and I have already made changes to some of them, like the Cien being moved to the new dealer because it never made sense in classics to me. GT4 doesn't seem to have any consistent logic to its selections but I'm thinking of moving anything pre-2000 from new to classics unless it was still in production in 2004.

You're right about the GT3 mod too, it's basically a compilation of all content that was available in some sort of GT3-compatible format. GT4 is more or less a new generation and is only compatible across its own builds.
 
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To my knowledge this is possible because GT4 Prologue, GT Concept and all other demos (Prius edition etc.) use the same game engine as GT3. GT4 uses a different engine so, for now at least, porting cars is not possible.


A question for @TheAdmiester. It is possible to change in which dealership cars are sold? Theese are some of the oddities i spotted and where I would place them:

Chevrolet Corvette C5R in new dealership
Panoz Esperante in classics dealership
Buick Special in tuner village or "full model" in tune shop
Eagle Taloon in classics dealership
Aston Martin DB7 in classics dealership
Jay Leno Tank Car in new dealership
Bentley Speed 8 in new dealership
Lotus esprit GT350 in classics dealership
Citroën Xantia in classics dealership
Citroën Xsara Kit Car in classics dealership
Audi R8 LMP in new dealership
BMW Mclaren F1 GTR in classics dealership
Hyundai Tiburon Turbulence '99 in classics dealership
Honda Gathers Drider Civic in classic dealership
Subaru Impreza 22B Rally Car in classics dealership
Is there a defined cutoff for the classics aside from these exceptions? Is it like 1995 or something?
 
Is there a defined cutoff for the classics aside from these exceptions? Is it like 1995 or something?
Not really. In the classics you can find cars that have some historical relevance and were not in production in 2004, thats why sometimes you can find early 2000s models. However i wouldn't consider a 2 years old LeMans prototype a "classic" just because it stopped racing in 2002.

Personally, i would put there only pre-2000 cars that are historically relevant, or rare and not in production. However, some flexibility is needed imho. For example I would still put the 1999 Ford Focus WRC in new car dealership because it was still racing in 2004 albeit not in that particular form (it was updated in 2003 with the Focus RS WRC but still).
 
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I assume it's different to GT3? Someone has been adding cars from GT4 variants into GT3




Interesting.

Even though GT4 is (probably) the best GT game and I love it, to me GT3 had a better driving engine, not to mention the non-stiff cameras.
 
Bought a PS2 last week for real hardware testing, had some hurdles, those hurdles are now mostly cleared, so I'm pleased to be able to show this:


Basically the additional cameras and the GT3-style chase cam were implemented using actual C code plugin hooks to the game's executable. Turns out the plugin was hooking in a way that the real hardware didn't like, but after some troubleshooting with the author of the plugin maker it's now working accurately.
 
So that means we would be able to buy you a copy to play on the real hardware without the need of modifying anything ?
Count me in !
 
Bought a PS2 last week for real hardware testing, had some hurdles, those hurdles are now mostly cleared, so I'm pleased to be able to show this:


Basically the additional cameras and the GT3-style chase cam were implemented using actual C code plugin hooks to the game's executable. Turns out the plugin was hooking in a way that the real hardware didn't like, but after some troubleshooting with the author of the plugin maker it's now working accurately.

Nice.

There are GS codes for retail that allow the car model to stay visible while using the in-car view but, it is even better to see what you have here by aligning the view to be horizontally moved in front of the steering wheel, though I guess it will take some work to align it for all models which have a detailed interior.
That brings me to one more question: Will it be possible to drive top-down convertibles in actual races?

Years ago when I was hacking the retail version, I made a code that allowed you to take any car (including ones like the Caterham) into an actual race but it froze upon loading.
(I also made a code that allows any car to be taken into GT Auto. Swapping rims on certain unique or race cars can be very funny.)
 
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Nice.

There are GS codes for retail that allow the car model to stay visible while using the in-car view but, it is even better so see what you have here by aligning the view to be horizontally moved in front of the steering wheel, though I guess it will take some work to align it for all models which have a detailed interior.
That brings me to one more question: Will it be possible to drive top-down convertibles in actual races?

Years ago when I was hacking the retail version, I made a code that allowed you to take any car (including ones like the Caterham) into an actual race but it froze upon loading.
(I also made a code that allows any car to be taken into GT Auto. Swapping rims on certain unique or race cars can be very funny.)
Cameras have been aligned to the proper dashboard position for every single car, already done and no more work needed as far as I can tell.

It is possible to force top-down model in races but I'm of the belief that PD did it for a reason. The animated drivers and more detailed models take up more memory and as a result are only fully fully tested to work with two on track. Three or four may be possible but to be perfectly honest I'm not inclined to run through every single possible combination of convertible cars just to make sure it all works, I think it's more trouble than potential gain.

There are some videos out there showing 6 convertible cars on track, but again considering the lack of testing I wouldn't declare it safe - there are some combos of cars/tracks/sounds etc that might just happen to work but I would rather have an experience that's as refined as possible, and leaving people with the potential for crashes is not something I would like to do (see the unknown pre-race settings menu crash that some had in GT4 Randomizer).
 


I agree.



I am surprised that PD did not do more to try and perfect sound of one of the best sounding Inline-6 engines ever made. If you listen to a stock BNR32 Skyline GT-R or stock BNR34 Skyline GT-R from Forza Motorsport 2, and then watch the video by SaabKyle04 about the BNR32 it sounds (nearly?) identical.


That grill need to go, though.
 
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Was never quite happy with how GT4 depicted Oxfordgrun on the E46 M3, finally got around to fixing it tonight.

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Was never quite happy with how GT4 depicted Oxfordgrun on the E46 M3, finally got around to fixing it tonight.

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How easy is it to tweak colors in GT4? I imagine it's much easier than GT2's palette swapping mess. If so, I can see myself doing a deep dive into some of the paint options and tweaking/adding them for accuracy. I know GT2's color choices often didn't match reality at all, not just in terms of appearance, but also as far as what colors were actually offered on the cars at the time. I have no idea how accurate GT4 is in that regard.
 
How easy is it to tweak colors in GT4? I imagine it's much easier than GT2's palette swapping mess.

As far as I understand it, instead of just having a set of separate palettes per colour, GT4 has one base set then effectively a set of instructions for how the game should byte-by-byte patch that to generate the other sets. It sounds a lot more complicated to edit.
 
How easy is it to tweak colors in GT4? I imagine it's much easier than GT2's palette swapping mess. If so, I can see myself doing a deep dive into some of the paint options and tweaking/adding them for accuracy. I know GT2's color choices often didn't match reality at all, not just in terms of appearance, but also as far as what colors were actually offered on the cars at the time. I have no idea how accurate GT4 is in that regard.
It's about as complicated as it gets but very versatile. Pez is correct in that each car's "colour data" is actually a patch file that tell the game how to edit the base model, in this case changing the palette pixels that are applied to various parts of the texture.

It's a pretty neat system honestly, you could in theory have a "colour" that turns off anything that's modelled a separate shape on a car, like hiding the licence plate or possibly even a wing.
 
It's about as complicated as it gets but very versatile. Pez is correct in that each car's "colour data" is actually a patch file that tell the game how to edit the base model, in this case changing the palette pixels that are applied to various parts of the texture.

It's a pretty neat system honestly, you could in theory have a "colour" that turns off anything that's modelled a separate shape on a car, like hiding the licence plate or possibly even a wing.
Interesting. It would be nice to have a separate 1996 240SX without the wing.

Also, could options be made/added to disable car restrictions (race any car on any track) and and an option to disable tire damage?
 
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