Final Fantasy VI Modding

[jshackles]

So, Final Fantasy VI released on Steam today! I decided it might be worth looking into doing character sprite replacement in this release since it's already been done for the PC version of V. In this game, characters typically use the same sprite sheet throughout the entire game, so I figured it might not be as daunting a task as V which would require every character/job combination to be replaced.

Anyway, much to my dismay it appears that unlike V, VI was released using the Android version as it's base. As such, the majority of the data is stored and encrypted using an Opaque Binary Blob[en.wikipedia.org] file (main.obb).

I've attempted decompiling this file using the Android SDK jobb utility, but it's throwing errors because the secret key (password used for encryption) is not correct.

I'm wondering if anyone else has had any luck with this or perhaps someone with more Android experience could shed some light on whether or not it's even possible to decompile/recompile this container.

[RiverNyxx]

Diposting pertama kali oleh Monterossa:

Did you fix the self-applying issue that the progress bar is not showing on top? some end users are having problem installing our mods because they think that the mod appliers are not doing anything since they can't see the progress bar.

I hadn't heard of that. I'll put it on my list of things to look into tho, thanks for the report!

[madsiur]

Hello,

So I guess this is the main thread? :)

I've been following this since the end of November and I'm quite surprise of the progress made so far, especially with Nyxo's extractor. I'd like to soon jump on the train too but my forces are more data finding and coding. I've been modding FF6 on SNES and GBA since 2011. I have not a complete mod finished but I coded and editor for the GBA version and currently developping (well on and off) a editor for the SNES version that will allow various expansions.

A simple assumption I have is that some data might be in similar format than in the SNES version. As an example, if the HP of a monster is on two bytes in the SNES version, it's probably the same in the PC version monster data. While there is probably similarities for this example, maybe not all the data format is the same (I'm thinking of monsters immune/weakness status that could be stored in another way than on a bit flag). Anyhow, I'll play with the extractor and try to locate data patterns soon and eventually report back here if I find something. I'm aware the PC version vs the SNES/GBA ones are completely two different things so I'm not setting my hopes to the roof yet.

Also if someone has info on the flb format (other than being a 32-bit ARBG format) I'd like to code an flb extractor if FF6 has any graphics (weapons?) stored under that format (already done here[www.vg-resource.com] but link is dead). I have a good background in coding so it's something I'm capable to do.

Graphics mode are cool but I hope we'll be eventually able to go as far with the PC version than the SNES version which is one of the most if not the most documented game (which makes it the most easy one to mod).

[Krisan Thyme]

Diposting pertama kali oleh madsiur:

Hello,

So I guess this is the main thread? :)

I've been following this since the end of November and I'm quite surprise of the progress made so far, especially with Nyxo's extractor. I'd like to soon jump on the train too but my forces are more data finding and coding. I've been modding FF6 on SNES and GBA since 2011. I have not a complete mod finished but I coded and editor for the GBA version and currently developping (well on and off) a editor for the SNES version that will allow various expansions.

If you want, send me a friend request sometime, I'll see what I can do to help get you started. You might be surprised how useful your current research will prove to be on this.

[madsiur]

Diposting pertama kali oleh Krisan Thyme:

If you want, send me a friend request sometime, I'll see what I can do to help get you started.

Thanks! I couldn't send you a request since Steam tells me your friend list is full. For now I coluld only follow you. :/

I'm going to sleep a few hours and start looking a the game file system.

[RiverNyxx]

Hey madsiur, it sounds like you might be the kinda person who can help a lot in our understanding of a few specific aspects of the steam release!

Feel free to send me a friend request, and I can give you all the info you want~

As a side note, the steam version of FFVI literally has a byte-for-byte copy of the original Japanese GBA rom inside it (except for a single byte that's different) -- I've been doing bits and pieces of research against it, but have been more hopeful for a GBA rom hacker to show up that I can work with instead~

On FLB files: I'm already working on that file format (and AKB, and PVR, etc..) so that I can add support for them in FFVI_Explore, however I don't want to discourage you from writing your own tools if you want to! :)

[madsiur]

Diposting pertama kali oleh Nyxo:

As a side note, the steam version of FFVI literally has a byte-for-byte copy of the original Japanese GBA rom inside it (except for a single byte that's different) -- I've been doing bits and pieces of research against it, but have been more hopeful for a GBA rom hacker to show up that I can work with instead~

Most GBA data is the copy of the well documented SNES data (excluding graphic, font and music related data but irrevelant here anyway). I can test the known GBA data types and come up with a rom.bin map and data formats document that could be useful for the community. Also it might be interesting to check if the exe use the pointer tables of the ROM and its ARM code.

What is lack of is ARM knowledge. I know the FF6 SNES ASM code well enough but I have no knowledge of the GBA counterpart. So I'd be of little help if it's used by the game.

Diposting pertama kali oleh Nyxo:

I'm already working on that file format (and AKB, and PVR, etc..) so that I can add support for them in FFVI_Explore, however I don't want to discourage you from writing your own tools if you want to! :)

That is great! I'd be more willing to write a map, event and stats editor that would handle the rom.bin data, which I should start in tandem with the document mentionned above.

Edit: Why am I unable to send friend invite to anyone? ("Their list is full" error message...)

[Saftle]

Diposting pertama kali oleh madsiur:

Why am I unable to send friend invite to anyone?[/b] ("Their list is full" error message...)

I took a look at your profile, and it appears you don't have any games. Steam has a "Limited User Account" system for accounts that don't have games yet. You have to spend at least $5 USD from the store to remove the limited status. They added that as way to filter out bots, since botters would have to purchase games to add friend invites.

You can find more info here: https://support.steampowered.com/kb_article.php?ref=3330-IAGK-7663

Also, in the past people could give you any 3rd party Steam redeemable CD-Key to activate the account, but now it actually has to be purchased through the store.

[RiverNyxx]

As a note, madsiur's friend invite arrived for me just fine.

Yeah, I highly suspect that the game is just using the rom.bin as a "super-database"-- that is, for all of the information used by the game, such as items, monsters, town layouts, AI scripts, and how they all relate; plus lots of other data that isn't actual executing code. Minus, of course, the graphics and audio, as those are external to the rom.bin, at least as used by the .exe.

I figured the GBA version was largely the same as the SNES version, but since I haven't really poked at either before, I thought I'd check with somebody who has first, instead of re-inventing the wheel, so to speak. ^-^ I've poked at ARM stuff a bit in the past, so I might be able to help in that department at some point, but I highly suspect that'll be unneeded, if my above assumptions about the "super-database" are true.

[Krisan Thyme]

Diposting pertama kali oleh Nyxo:

As a note, madsiur's friend invite arrived for me just fine.

Yeah, I highly suspect that the game is just using the rom.bin as a "super-database"-- that is, for all of the information used by the game, such as items, monsters, town layouts, AI scripts, and how they all relate; plus lots of other data that isn't actual executing code. Minus, of course, the graphics and audio, as those are external to the rom.bin, at least as used by the .exe.

I'd say it's not a suspicion so much as a fact at this point. While a few things still need to be checked out, everything I've tested so far seems to indicate that this is exactly the case. It's an interesting setup, to say the least.

[terderrer]

Hey guys!! been following this for awhile now (really loved the defilter mod) . I do alot of pixel art and photoshop editing so i like to help anyway i can.

Also any chance for non cosmetic mods? like ones to change the battle system to look and act like it does in the gba/snes versions?

[RiverNyxx]

Unfortunately, chances seem pretty low on that one, despite how highly requested that mod is. :(

[pluckylump]

Any chance all this programming magic talk will lead to higher resolution sprites being loadable?

[RiverNyxx]

It's on my todo list to look at later, but I have other things to take care of for now ^-^
There's a chance we might be able to figure something out tho~

[pluckylump]

Diposting pertama kali oleh Nyxo:

It's on my todo list to look at later, but I have other things to take care of for now ^-^
There's a chance we might be able to figure something out tho~

Not having to cram detail in pixels would make editing the sprites so much easier, and the art so much more consistent. It's so weird that there's different resolutions for different aspects of the game.

[madsiur]

It's a great era to be alive!

Events can be modified:

http://imgur.com/wnzyFUa (dialogue entry change)
http://imgur.com/KjWaGDp (Battle invoke pack change)

Enemy AI can be modified:

http://imgur.com/3BVPOVC (guard casting stop)
http://imgur.com/RLcZnJH (guard casting life 3 on self)

Enemy stats can be modified:
http://imgur.com/dkWT7Jy (enemy EXP change)

I'll say mostly what Krisan stated: a lot seems to be fetched from the ROM. I still want to make tests with the following:

• magic/espers/blitz/swtech/etc.. data (255 entries considered as "spell" data)
  
• Chest data (already confirmed by Krisan?)
  
• Item/weapons/armor/relic/etc... data (255 entries) +14 new weapons
  
• Formations data / Pack data (a pack is a group of 4 formations maximum used for random encounters)
  
• Shop data
  
• Esper data (which spell learned at which rate)
  
• Weapon / Spell animation strings (I suspect changing these will have no effect)
  
• Colosseum Battle Data
  
• Characters initial data
  
• Item stolen/dropped table
  
• sketch / control tables
  
• Entrance / Exits points
  
• Event triggers
  
• NPC data
  
• Map data (already confirmed by Krisan?)

There's also other known data from the SNES version that hasn't been found in the GBA version (most likely because of format differences). I started the project of identifying as much as possible two years ago but dropped shortly the project after beginning something else. I think it's time to get back on that.

All this can easily be modified with a hex editor once you know what to modify and where. I'll stat putting up a hex modding document tomorrow with the rest of the tests mentionned above.