Resident Evil Veronica ISO/ROM Editor (PS2, GameCube, Dreamcast)

Started by Tony H, November 23, 2022, 10:15:41 AM

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Tony H

This started out as an ISO/ROM editor for the PlayStation 2 version of Resident Evil Code: Veronica X, but I might try to make it so it works on the GameCube and Dreamcast versions as well.  Part of the editor is based on a large table in the ISO/ROM that determines things like how much ammo your guns can hold, how much ammo there are in pickups, etc.  That table appears to be very similar in all 3 platforms, so that part would be relatively easy.  Lots of the other stuff that will be in the editor don't use tables (ie. enemy damage, restored health, starting weapon, etc) so those will be a lot different for each platform.  There are a few things that might make the 3 platform idea not work out so well, but will check it out.

Rough draft.  Will most likely add more tabs/pages to hold everything.



I'm hoping someone who is familiar with this game can answer a question: When starting a new game, is the Playing Manual necessary, or is it just for reference while playing the game?  One of the options in the editor will let you replace the Playing Manual with whatever weapon or item you want, but if the Playing Manual is needed somewhere in the game, I will have to figure out something else.
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BillyTime! Games

Just booted up the game to check. The playing manual is a one time use item. When selecting Use, the playing manual transfers over to your collected notes and disappears from your inventory.

Tony H

Quote from: BillyTime! Games on November 23, 2022, 05:43:03 PMJust booted up the game to check. The playing manual is a one time use item. When selecting Use, the playing manual transfers over to your collected notes and disappears from your inventory.

Thanks for the info.  Have never played the game before, so trying to get things figured out.  Changing the Playing Manual over to something else seems to work fine, and it sounds like the manual isn't really needed in the game.  I traded the manual for the Linear Launcher and had a lot of fun destroying the first set of Zombies. lol.
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Tony H

Editor update:

Looks like the editor will work fine on all 3 platforms (Dreamcast, GameCube, and PlayStation 2), at least with the tables for weapon ammo capacity, ammo pickup amounts, etc.  Haven't tested the rest of the stuff yet on Dreamcast or GameCube.

One of the concerns was the search time being too long with such large files (1.2 ~ 1.9 GB) when using a pattern search method.  It was taking too long at first, but have made some changes and gotten the search time down to about 3 seconds, which doesn't seem too bad.  Still have a lot more to add which will make the search time longer, but I'm guessing only a few seconds more.

List of games it will work on:

PlayStation 2: RE Code: Veronica X (USA); Biohazard Code: Veronica Kanzenban (Japan)

GameCube: Should work on any version/region including USA, European, and the Japanese Biohazrd versions.

Dreamcast: Should work on any USA and European versions, and most likely the French, German, and Spain versions.



Got about half of these values (above) finished, and are being loaded from the ISO/ROM.  They load fine on all 3 platforms.

If anyone has suggestions on other stuff to add, let me know.  Have done a lot of reading and playing, and these seem like the most useful.



This tab (above) is for things like your health, how much damage enemies cause, etc.  Might add more enemies in the future if there is any interest.

All of the testing on this page was done on the PS2 version, but have found similar code in the GameCube version.  Pretty sure most or all of this will work on all 3 platforms.


I do have a question for anyone that's familiar with this game.  Is an adjustment that lets you increase the number of ink ribbons you get necessary?  You normally get 3 of them on pickup and are used for saving your game.  Would more than 3 be useful?

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KiryuRealty

Don't change the amount of Ink Ribbons picked up, it will screw up the balance of the game to do so.

The number of times the player saves has an effect on the ending and rewards, and the limited amount of ribbons, combined with the placement of save rooms, is how the game guides the player to find the most efficient way through the game. Once you have learned the layout and enemy locations of a section, the expectation is that you can simply take the right path and have the right gear to avoid needing to save in the first place. The classic Resident Evil games weren't meant to be finished on your first play, they were very much influenced by old-school adventure games, where every time you played, you learned a little more until you could make it to the end and win.

Felipefpl

Kongrats for your work, you seem to be on firah. 1st Road Rash 2 and now Code: Veronica  :thumbsup: (a game that should get more love since it was the last RE with the classic camera.

I was wondering if you are into improving old stuff, there are other things that deserve a work like yours here:

https://www.romhacking.net/abandoned/
Core i7 Celeron Sandy Bridge G460 1.8 Ghz - 4 GB RAM - Win7 x64 - Intel HD Graphics 2000


BillyTime! Games

Quote from: Tony H on November 28, 2022, 02:22:44 PMI do have a question for anyone that's familiar with this game.  Is an adjustment that lets you increase the number of ink ribbons you get necessary?  You normally get 3 of them on pickup and are used for saving your game.  Would more than 3 be useful?

Normally three should be enough as you get more throughout your playthrough. You wouldn't find yourself in a situation where you would run out of saves unless you saved every other room.

Would it be possible add an option to unlock Battle Mode by default? Its a short mode where you race to the end and face multiple enemies. You even get to play as Albert Wesker in this mode. This is unlocked by completing the game. You also get a First Person mode where completing the game for the first time.

Tony H

Thanks for the info on the game saving guys.  I will take the advice and remove the ink ribbon option from the editor.

Felipe, as far as working on those abandoned projects, I did look at that Zelda 4 utility at the very bottom about a year ago.  My slightly outdated software couldn't even open it because it was so old, so not even sure what it does.  May go back to that one later.  Not really interested in any of the others.

BillyTime, I will look into that Battle Mode option.  Since I think each of the 4 characters in the game have their own stats for weapon ammo and ammo pickups, I should probably get to where I can play as Albert Wesker to make sure the editor is doing things correctly.
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Tony H

Wanted to post some information about the game mechanics while I still remember.

Zombie health:
When I first started figuring out zombie health, I noticed that some of the same zombies would have different amounts of health if I started a new game.  It looks like the game randomly chooses the amount of health from a table.  I'm guessing they did this so the number of shots it takes to kill them isn't predictable.  By setting all of the values in that table to zero, you can kill zombies with 1 hit.  The editor will have an adjustment for each one of the values, so you can keep the randomness if you'd like.

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Zombie damage:
The way the game calculates how much damage you get from zombies attacks is a bit unusual.  Like many things in this game, there is a table for the amount of damage zombies cause.  What is unusual, is that several of the zombie types have a value of zero for their damage, while others have values of 5, 8, etc.  What the game does is that anytime you're attacked by a zombie, there is programing (which is not part of a table) that subtracts 10 from your health.  When the game looks up that zombie's damage value in the table, it will also subtract that value from your health.  If that value is zero, you will only lose 10 health.  If that zombie's damage value is 5, your total amount of damage would be 15, and so on.

Keep in mind that adjusting that "base" value of 10 should apply to all zombie attacks, while adjusting the other values (see the screen shot in a previous post) will only apply to specific zombies.  There are 3 specific zombie values in the editor.  By setting these 3 values to zero and setting the "base" value to zero, this gave me zero damage from every zombie I encountered for the first 30 to 45 minutes of game play.  There are other damage values in that table, so I may figure out who they belong to and add them to a future editor update if there's any interest.

Some of the zombie damage values from the table:

Burning Zombie (the first zombie you see in the game) = 5 (total damage is 15 (5 + 10/base))
Graveyard Zombies (the second zombies you see in the game) = 0 (total damage is 10 (0 + 10/base))
Trainee Zombie (not sure if that's the right name) = 8 (total damage is 18 (8 + 10/base))
Prisoner Zombie (again, not sure if this is the right name) = 5 (total damage is 15 (5 + 10/base))
Other zombies (not sure of the names) = 0 (total damage is 10 (0 + 10/base))

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Zombie Dog damage:
They way the zombie dog damage is done is a lot different than zombie damage.  This info is only for the first two zombie dogs you encounter in the game, so not sure if it applies to other types of zombie dogs.

There is no table for the amount of damage that dogs cause.  Instead, there are three different values that can be subtracted from your health and these appear to be randomly used.  The three different values are 6, 8, and 12.


EDIT: Most of the info above was for the PS2 version, not sure yet if it's the same on GameCube or Dreamcast versions.
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Felipefpl

QuoteFelipe, as far as working on those abandoned projects, I did look at that Zelda 4 utility at the very bottom about a year ago.  My slightly outdated software couldn't even open it because it was so old, so not even sure what it does.  May go back to that one later.  Not really interested in any of the others.

I see, good to know you may come to try the zelda's tool. A pity about the others, i was hoping you could put some life on them. ;)
Core i7 Celeron Sandy Bridge G460 1.8 Ghz - 4 GB RAM - Win7 x64 - Intel HD Graphics 2000


Tony H

Update:

About 50% done with the editor.



Rearranged a few things.  Also added a button that shows a list of all the weapon ID numbers so you can choose which weapon you want to start with and how much ammo.  If you want to start a new game with any item or ammo, you can do that as well. 

I noticed that the Japanese/Biohazard version loaded in the screenshot above gives you 200 starting health instead of the 160 starting health in the USA version.  I read that the Japanese version has three difficulty levels (very easy, easy, normal), where the USA version only has one.



Got this page (above) so all the values are being loaded from the ISO now.  Changed the values that are displayed for the amount of health that gets subtracted from dog attacks from negative values (which is what is used in the game) to positive values so it's consistent with the rest of the editor and easier to use.


Now that everything is being loaded from the ISO/ROM, the initial wait time for loading all the values is about 9 seconds for the PS2 version and a little shorter for the GameCube and Dreamcast versions.  Clicking on the "Show values from ISO/ROM" buttons only take about 1 second to display, since everything is already in memory.  These times may be faster or slower depending on your computer.

Added a kind of safety feature where the editor checks to see if any of the values it was searching for weren't found.  If it detects a problem, it will give you a message.  If it finds a problem, you can still use the editor but it may not patch all of the values into your ISO.  The main reason for this is because the editor is setup to work on other versions of the game that I never tried/tested.  There are a ton of different versions of this game on the 3 different platforms.  If you get that message, it's probably best to try a different version.

Everything in the editor works on the PlayStation 2 version, but as mentioned above, there are a few adjustments that are not available with the GameCube and Dreamcast versions.  May get those working in a future update.

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