[RELEASE] Biohazard 1.5 Hacks

[Graco]

How difficult would it be to replace an ammo type with grenade launcher ammo data from RE2 so that the same results could be achieved?

[Upaluppa]

How difficult would it be to replace an ammo type with grenade launcher ammo data from RE2 so that the same results could be achieved?

That's what IGAS has been doing, but it far exceeds my knowledge, I'm sorry...
For now we'll have to do without working hand grenades, flame throwers, grenade and rocket launchers I guess.

One really cool update we might get soon are fixes for the SPAS-12 (without Gameshark) and the disappearing Zombies and headless Zombies not staying dead bugs. SolidSnake11 (https://www.youtube.com/user/roberto67024/videos) has made some promising progress with these!

That's probably the best thing we can get until IGAS releases their restoration project.

As much as I'm interested in learning how ASM and PSX code injection works, I simply don't have the time to look into it.
It's not something you can learn over the course of a few weekends...

[Graco]

Ah, I see. Thanks for all these codes though. Can't wait to get a chance to try them out.

[AleX_Red_07]

I apologize if a little off topic.
Recently I figured in technology analysis and collection psx games.
I understood biohazard 2 beta 2, and reassemble it so that it is fully working, that is, XAS and STR files also work.
After this success, I decided to replace the background of TITLEJ.PIX bio2trial for bio2beta.
After CAPCOM video game that does not show.
Why is that?
After all files have the same size?
Please help me that I gave wrong?

---------------------------------

And how it is possible to replace the RDT or BSS files if it is possible?
If you can edit through the hex rdt and EXE files that is whether what may be a small tutorial about it? Thank you =)

[Upaluppa]

SolidSnake11 just released a new patch which fixes the "killed Zombies getting up again" bug:

https://www.youtube.com/watch?v=zUY5uLBi4xE

Apply the patch to a clean MZD/Vanilla image, it includes all of DB's changes as well!
Now all I need is a fix for the disappearing Zombies and I'll be satisfied till IGAS releases their project!

Edit:
Unfortunately this new patch breaks the Zombie AI...
It does fix the "not staying dead" problem, but Zombies will no longer actively pursue you when you use the patch.
They'll wander around aimlessly unless you are close to them.


@AleX_Red_07:
I'm not sure I understood your question correctly.
You can use CDMage to open an image file and replace the .RDT and .BSS files inside, if that's what you meant.

You can find CDMage here:
http://www.geocities.ws/cdmage/frames.html

[AleX_Red_07]

Dear!
Thank you for your answer, but I know how to use CDmage fine.
However, the substitution in the BSS or RDT BIO 2 BETA v2 after replacement leads to possible inoperability of the different files sizes.

I went the other way, with the help of CDmage I pulled the files from the image, replacing the file (BSS RDT or PIX) after taking of the Trial
version, and again assembled a working drive with just a few tools.

Unfortunately this does not lead to any results. I even used the BSS Editor to replace that image at a location and
once it reaches the game hangs.

PIX file (the title of the screen image) is identical in size but does not start the game after the CAPCOM video.

With RDT exact same problem. Biohazard 2 Sourcenext takes RDT of PSX version and working.

Biohazard 2 beta v2 does not accept RDT from BIO 2 TRIAL and any other files. Why is that?

[Upaluppa]

Dear!
Thank you for your answer, but I know how to use CDmage fine.
However, the substitution in the BSS or RDT BIO 2 BETA v2 after replacement leads to possible inoperability of the different files sizes.

I went the other way, with the help of CDmage I pulled the files from the image, replacing the file (BSS RDT or PIX) after taking of the Trial
version, and again assembled a working drive with just a few tools.

Unfortunately this does not lead to any results. I even used the BSS Editor to replace that image at a location and
once it reaches the game hangs.

PIX file (the title of the screen image) is identical in size but does not start the game after the CAPCOM video.

With RDT exact same problem. Biohazard 2 Sourcenext takes RDT of PSX version and working.

Biohazard 2 beta v2 does not accept RDT from BIO 2 TRIAL and any other files. Why is that?

I really don't know why it crashes, but there must be a way to make it work.
MarkGrass released a hack of Biohazard 2 Beta 2 which replaced the title screen with the one from 1.5 and imported rooms from that game.

I've reuploaded it, here:
http://www.mediafire.com/download/4s..._Bio15_Mix.zip

[AleX_Red_07]

Oh, I remember this test!
Thank Upaluppa!

Unfortunately, it did not help me.
I just wanted to take assets from Bio2Trial and impose them on the Bio2Beta v2, but nothing leaves.

[MeganGrass]

I just wanted to take assets from Bio2Trial and impose them on the Bio2Beta v2, but nothing leaves.

There are several reasons why this won't work by using simple file swap techniques:

RDT data from the Trial version uses a completely different structure. In fact, it's closer to Bio1.5 than retail. Therefore, the RDTs from the Trial must be completely rebuilt for proper use in retail.

Some script opcode bytecode structures are different from retail and simply not compatible. In such cases, the incompatible script opcode bytecode from Trial runtime data must either be converted to retail standard or removed entirely.

The Bio2 beta and all retail builds utilize multiple file checksum routines; archive file containers (BSS, EMS, ITP and others) use special code and tables that can't be fixed by patching the "Cd_read()" function alone.

If you add/remove anything from any build of Bio/2/3, you must update the global "fpos" structure to reflect the changes, which include: File Size, File Sector and File Checksum. Otherwise, the game will enter into an infinite loop trying to read what it would consider to be corrupt data.

In addition to all of that, the BSS archive file containers use a unique file size table that must also be updated to reflect any changes. Any error will result in either one of two things: Black screen of death or visual corruption.



What you're trying to accomplish requires extensive hacking which is made especially easier with assembly hacking.

[AleX_Red_07]

Well, not so simple as it should.
But I thought that might be the difference in file structures.
It is evident to me here that does not shine.
Thanks for the explanation Mark!

That is, except "hex" nothing I can do?

[MeganGrass]

Well, not so simple as it should.
But I thought that might be the difference in file structures.
It is evident to me here that does not shine.
Thanks for the explanation Mark!

That is, except "hex" nothing I can do?

Hex editors are primarily for the purpose of quick edit/reverse engineering and really not meant to replace the need for external application. Additionally, you won't be able to read/modify/create/compile the necessary MIPS r3000a assembly with a hex editor.

For a task of this magnitude, it's for the best to setup a tool chain and let it work the magic during ISO compilation; I did it for that old project that Upaluppa linked, in fact. Suffice to say, I do the same for the current iteration of the project.

It is at this point that you have the daunting task of developing the tool chain, which one would absolutely require some kind of skill in program development.

Really, there is no convenient way to go about it.

[AleX_Red_07]

Okay, thank you.

[Upaluppa]

I just had a random creepy moment:

That's the first time I actually jumped out of my seat while playing 1.5.

By the way, the Manspider in Corridor 2-A makes some rather unnerving noises if you mute the music.

[AleX_Red_07]

WTF LOL =D

[Graco]

...what.

How? Why?