NHL2K editing (technical discussion)

[nikethebike]

I started this thread due to the recent breakthrough on 2K10 roster editing: https://forums.operationsports.com/f...0-utility.html


In order to open up the possibilities for us to edit more 2K games, for example 2K11 (2KHS) I'd like for this discussion about research on the games to be public, that way knowledge and research will not be lost with individuals leaving the community.


Please try to keep this thread on topic and technical, but if you know something, don't be afraid to share it!

[nikethebike]

Re: NHL2K editing (technical discussion)

First of all I would be really interested in what we know about the save file format of NHL2K10.
How is the data structured and at what offsets can we find specific data in the file?


If we update say a player name, do we need to edit anything else to make it load successfully in the game?

[nikethebike]

Re: NHL2K editing (technical discussion)

Here is what I found myself about the NHL2K11 save file:
1. At offset Hx213CE0 the edited player names are stored.
- They are stored as normal characters padded with a Hx00 between them.
- After each word/name three Hx00 marks the name as finished
- Just hex editing these names in the file does not work. The game says that the save file is corrupt.
- When you change a name in the game, the game adds to this list of names, it does not overwrite words, which is bad since the save file has fixed length. This means eventually you will run out of place for text edits.
- The space for edited names seem to go somewhere up to 2236E0 - since that area is padded with zeroes.
5. At offset Hx2236E1 I found Getzlaf and the rest of the standard player name strings in the game.
- These name strings seem to end at Hx22971C
6. After this comes a strange area. In it I found 2 strings, First and Last. Rest of the data are Hx2A Hx00 repeated...
7. At Hx22FBC9 I found strings for arena names, cities, teams, shortnames etc.
- This ends at 231216
8. At Hx2315AB I found countries, coach names, a lot of names and different strings you can find in the game.
- This ends somewhere at Hx241E1B


I tried changing a couple of strings but never succeeded, the game said that the file was corrupt. I suspect there might be a checksum somewhere.

[snowdrift]

Re: NHL2K editing (technical discussion)

Here is what I found myself about the NHL2K11 save file:
1. At offset Hx213CE0 the edited player names are stored.
- They are stored as normal characters padded with a Hx00 between them.
- After each word/name three Hx00 marks the name as finished

Good news as that is exactly how 2K10 works, except the name list is at a different address.

Just hex editing these names in the file does not work. The game says that the save file is corrupt.

I took a quick look at various Wii forums and it seems most Wii saves do use a checksum. There's no point in discussing anything until the checksum isn't figured out so I suggest researching that, maybe reach out to some people with experience on Wii/Dolphin forums. If you find a good one we could even move our entire discussion there.

- When you change a name in the game, the game adds to this list of names, it does not overwrite words, which is bad since the save file has fixed length. This means eventually you will run out of place for text edits.

My utility erases the entire list and only writes in the names provided in the CSV file. It also never writes duplicates (sometimes the same name appears twice in the default 2K10 file which wastes space unnecessarily).

[nikethebike]

Re: NHL2K editing (technical discussion)

OMG... It might be as easy as the first four bytes in the file being the checksum...
Will see if I can find how it is calculated.

[nikethebike]

Re: NHL2K editing (technical discussion)

Well, the "easy way" to calculate the sum, was not the right one. Will probably need to learn more on dolphin debugging.

[nikethebike]

Re: NHL2K editing (technical discussion)

Some progress... Been digging around a bit and my current approach is pretty much guess work, trial and error. Been using calculate methods available in HxD but nothing has worked yet. Getting closer to having to learn dolphin debugging.

[nikethebike]

Re: NHL2K editing (technical discussion)

Found an extremely interesting text on the NBA series: https://forums.nba-live.com/viewtopic.php?f=150&t=88190


It has a 4 byte checksum at pos=0...

[nikethebike]

Re: NHL2K editing (technical discussion)

OMG, it was that easy...


It is a CRC-32 checksum.



You just remove the first 4 bytes (the checksum) and calculate it from the rest of the file...


Now I want to know more about the file format so that we can start editing players this way.


The first ever save game edit outside of the game:



Say hello to William Nylleter!

[DJ NEO]

Re: NHL2K editing (technical discussion)

Yep, these guys have a long experience with modding the NBA 2k. I wouldnt be surprised at all if their tools works for the 2k10/11 hockey as well.

These games are all coming from the same studio- Visual Concepts, as we know.

These guys can even mod the sounds of NBA 2k, so maybe they can point you somewhere...?
I stopped when I realized there are just 2 big files 0A and 0B in the 2k11 iso.

And then I rather shifted focus back to gameplay and graphics, otherwise it would never would be done.

[snowdrift]

Re: NHL2K editing (technical discussion)

OMG, it was that easy... It is a CRC-32 checksum.

I'm floored. This is incredible news. I figured it would be a lot more difficult than that. I don't have time to document the 2K10 save right now but I'll send you a PM in a bit to see if I can get you a head start.

[nikethebike]

Re: NHL2K editing (technical discussion)

If the file format is similar between PS3/360/WII I might be able to use a method I used when I was editing WWE SVR 2010, that is just using a save file compatible with the editor I created as an envelope for the data I wanted to edit then just export/import that data section between different game versions.


That way perhaps we don't even need to mod your tool to be compatible with NHL2K11, the only thing needed is a way to replace the PS3 data with data from the 2K11 file and vice versa.


From a programmer point of view this is ugly as F, but might save a lot of programming hours.

[snowdrift]

Re: NHL2K editing (technical discussion)

That's a great idea. But if the sections in the save file are exactly the same, theoretically it's just a matter of changing certain constants in the code. There will probably be some bad design to work out here and there, but I don't think it would be a huge hassle.

[nikethebike]

Re: NHL2K editing (technical discussion)

I'm looking into it now to see what I can do.

[nikethebike]

Re: NHL2K editing (technical discussion)

Anyone have an already extracted savefile from PS3 I can use to compare the 2K11 file with?


Tried downloading brute force but the installer magically disappeared which make me think virus...