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Author Topic: Need help on possible decompression of a file.  (Read 2 times)
Babazoz
Guest
« Reply #30 on: January 29, 2008, 03:05:43 pm »

Quote from: Ryusui on January 29, 2008, 02:44:16 pm
It's not out of left field. Data corruption is a useful tool for figuring out the workings of a game. Just change bytes at random and see if the game breaks in any interesting ways. ^_^

I think you might want to change the 2-byte value at 08 instead: i.e. "13 E3" (E313). 0C77 seems to be a control code: all of the other strings have an 0A77 in between them.

That 13 is prevalent in all the script files.  0A signifies a line break.  The 77 I believe signifies the beginning of a new block of text.

The E3 0C seems to be the key to the whole problem.  When I zeroed it out, the text played without doing the confirmation of auto-skip or the intro movie.  When I played it all the way through and it got to the end of the script file's dialogue, it did the confirmation, and the intro movie, then crashed where it usually does.  So I'm almost certain it's a pointer.  The name of the intro movie is listed in the script file as well.  I've tried adding the difference in size to the E3 0C value, but no dice there with about 10 different combinations.
Ryusui
Guest
« Reply #31 on: January 29, 2008, 03:17:25 pm »

Oddbal question. Does that "Prologue" at the end display where it does in the script, or is it displayed before the script?
Babazoz
Guest
« Reply #32 on: January 29, 2008, 03:27:34 pm »

Quote from: Ryusui on January 29, 2008, 03:17:25 pm
Oddbal question. Does that "Prologue" at the end display where it does in the script, or is it displayed before the script?

That is actually displayed at the options screen in-game by pressing square.  Probably to denote the section for saves, etc.
Ryusui
Guest
« Reply #33 on: January 29, 2008, 04:55:28 pm »

But can it only be displayed after the preceding text has already been shown? If it can be displayed during the text, then there has to be a pointer aimed at it...somewhere.

Let's try another experiment. Open up the file in Windhex and go to "Increase/Decrease ROM size" (if you don't use Windhex but your hex editor has a similar function, that's okay too). Increase the file size by one byte (4,086 bytes), but don't change anything else. See if the game crashes. Also try doing the same thing but updating the size given in the header to match the actual file size.
Babazoz
Guest
« Reply #34 on: January 29, 2008, 05:58:45 pm »

Quote from: Ryusui on January 29, 2008, 04:55:28 pm
But can it only be displayed after the preceding text has already been shown? If it can be displayed during the text, then there has to be a pointer aimed at it...somewhere.

Let's try another experiment. Open up the file in Windhex and go to "Increase/Decrease ROM size" (if you don't use Windhex but your hex editor has a similar function, that's okay too). Increase the file size by one byte (4,086 bytes), but don't change anything else. See if the game crashes. Also try doing the same thing but updating the size given in the header to match the actual file size.

No on both counts. Sad  Earlier, I had an idea to completely zero out the text and leave the headers and other data intact, while rewriting the dialogue.  That didn't work either.   
Ryusui
Guest
« Reply #35 on: January 29, 2008, 06:20:22 pm »

Sounds like we're stuck unless we can run a tracer of some sort. -_-;
Babazoz
Guest
« Reply #36 on: January 29, 2008, 06:25:22 pm »

Quote from: Ryusui on January 29, 2008, 06:20:22 pm
Sounds like we're stuck unless we can run a tracer of some sort. -_-;

The only thing I have close to that is CWCHEAT, which runs behind the game, and when activated, can produce a memory dump, and an assembly dump, but no tracing.

I don't know. As long as it's understandable, I guess working within the boundaries of what's there is okay.  I don't like it, but if that's how it has to be, then so be it.  This game will probably never see the light of day outside of Japan, and a lot of folks would like to play it.

Thanks for the help all the same. Smiley
Ryusui
Guest
« Reply #37 on: January 29, 2008, 06:52:30 pm »

Remember, since it's all Shift-JIS, you have quite a bit of space to work with if the game can print ASCII characters. ^_^
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