News: 11 March 2016 - Forum Rules
Current Moderators - DarkSol, KingMike, MathOnNapkins, Azkadellia, Danke

Author Topic: [INFO - Help Wanted] (NES) Want to make a Guerilla War Uncensored patch.  (Read 1101 times)

releasethedogs

  • Jr. Member
  • **
  • Posts: 67
    • View Profile
I want to make a Guerilla War patch to make it more like the Famicom version (Guevara).

where do I start? What ROM should I use?

 NES version?
It's translated already But... I have to change the text (add missing elements). I'm under the impression you can't add info to a ROM. Might be a problem??
Also, edit title screen from "Guerilla War" to "Guevara".
Title screen is more interesting in this version... Has cool explosion effect.


Famicom Version:
Isn't Translated already but might have enough space to add in text.
Title screen is less interesting, lacks explosion effect.
BUT... Famicom version has a hidden port of the game "Sasuke vs. Commander" -- which is the only port this arcade game ever got.

I don't really know where to start. My main priority is editing the text and overcoming the space limits.

what programs do I use? I assume there is a way to export the titles as a picture, edit them in a paint program and then import the edited file?? How do I edit the text? Hex editor??

help!

SunGodPortal

  • Hero Member
  • *****
  • Posts: 2921
  • 2 + 2 = 5
    • View Profile
Quote
It's translated already But... I have to change the text (add missing elements). I'm under the impression you can't add info to a ROM. Might be a problem??

I suppose it depends on whether there is any free space left. At first glance it seems there is some but I'm not sure how much you will actually need.

Quote
Also, edit title screen from "Guerilla War" to "Guevara".
Title screen is more interesting in this version... Has cool explosion effect.

You'll want to use a program like YY-CHR to locate and edit the title graphics. You could probably cut and paste them out of the ROM but it would likely be simpler just to edit them where they are at.

Quote
BUT... Famicom version has a hidden port of the game "Sasuke vs. Commander" -- which is the only port this arcade game ever got.

Hmm. Never knew about that.

Quote
How do I edit the text? Hex editor??

I looked through the ROM and it appears that the text is stored in ASCII format, which means you won't have to worry about making a table file. You can just open the ROM up in a hex editor and type in text changes (but you'll need to pay attention to the formatting/control codes and likely have to figure out what each one does on your own via trial and error or observation, most that I noticed started with "FE", probably line breaks).
War is Peace. Freedom is Slavery. Ignorance is Strength.

releasethedogs

  • Jr. Member
  • **
  • Posts: 67
    • View Profile
I suppose it depends on whether there is any free space left. At first glance it seems there is some but I'm not sure how much you will actually need.

You'll want to use a program like YY-CHR to locate and edit the title graphics. You could probably cut and paste them out of the ROM but it would likely be simpler just to edit them where they are at.


I looked through the ROM and it appears that the text is stored in ASCII format, which means you won't have to worry about making a table file. You can just open the ROM up in a hex editor and type in text changes (but you'll need to pay attention to the formatting/control codes and likely have to figure out what each one does on your own via trial and error or observation, most that I noticed started with "FE", probably line breaks).
Firstly I'd like to thank you for answering my n00b questions.
Earlier I took the initiative to try and edit the words by myself. I was careful not to add any date only change and it corrupted the ROM. Any idea? You said there is some free space, how do you know? How much is there? How do I use it?
Sorry for all the additional questions, seems to be a Shaharazad effect where the questions are just going to lead to more questions in questions until the questions grow exponentially.  ;)

SunGodPortal

  • Hero Member
  • *****
  • Posts: 2921
  • 2 + 2 = 5
    • View Profile
Quote
Firstly I'd like to thank you for answering my n00b questions.

No problem.

Quote
Earlier I took the initiative to try and edit the words by myself. I was careful not to add any date only change and it corrupted the ROM. Any idea?

I guess it could be a number of things, but the first thing that comes to mind is stuff like the spaces between the words. When you put a space where there wasn't one previously make sure that the spaces that you insert are represented by the same hex values as what the original game uses as well as in other similar instances. For example, what may look like a period on the text side could be any number of different values on the hex side. You will also likely have to experiment with the control codes to document these yourself. There's no avoiding that since the game has not already been documented in this fashion.

Also, if you cut/paste some text into the ROM (which I would NOT recommend in this case) be sure that you are overwriting data as opposed to adding data. If you overwrite data it will only change what you have overwritten, but if you add data you are likely to ruin every bit of data that lies beyond it as everything that comes after the stuff you have inserted will now be shifted to different addresses than what the game expects.

Quote
You said there is some free space, how do you know?

I just skimmed through the ROM and noticed a few places where there were large groups of "FF" bytes (empty space). Anywhere you see a few rows of nothing but "FF" that means you've got free space.

Quote
How much is there?

Not sure. I did notice a few places but I didn't bother to count bytes or anything.

Quote
How do I use it?

Put something in these empty areas that you would like to include in the game and tell the game when and how to load it. I guessing that since it's an NES game this part could get pretty complicated. I'm not sure how straight-forward the addressing is and how different mappers effect it. I've mostly just worked with the SNES.
War is Peace. Freedom is Slavery. Ignorance is Strength.