JumpStart Haunted Island (PC, 1996) - some info

[bluecake]

I am currently trying to figure out how to rip image assets from an old PC game called JumpStart Adventures 4th Grade: Haunted Island. While there are still many things I don't understand, I have figured some things out and I would like to detail them here. I greatly appreciate any advice or insight, I'm not expecting anyone to simply rip the assets for me, but maybe someone will be able to give a few pointers. So here's what I have:

This game primarily uses .df files. This file format appears to be specific to the game's developer, KnowWare. Some other games developed by KnowWare, such as CatDog: Quest for the Golden Hydrant and JumpStart Pre-K, also primarily use this file type. As far as the .df files are concerned, it's actually very easy to rip audio from them. You can simply use the Import As Raw Data option in Audacity, then slow down the imported track by 150%.

So, what I'm interested in now is getting image assets from this game, but that's where I've hit a wall. The files I'm mainly looking at are island.df and map.df, which I assume must contain at least some data for graphics. Some files are named sound.df, sound2.df, and text.df, which are self-explanatory as to what they contain, and it stands to reason the game's graphics are stored in .df files as well. (I've checked the other disc contents and I didn't see any other file types that seem like they would contain graphics, I can expand this more if needed). When looking at the files in a hex editor, I noticed the text COMP showed up periodically throughout the files, but I don't know if this is significant at all, beyond simply indicating that the files are compressed, I guess

That's basically all I have for now. I'm thinking of trying to write a custom QuickBMS script or something, but as someone with no prior familiarity with that, it's a bit overwhelming. Not sure if that would even be a viable solution, but it's all I can really think of for now

[khafaz]

Hi bluecake!

I'm interested in the same game as you as I grew up with the JumpStart franchise.
I've also noticed that the string "COMP" in TEXT.DF is preceded by the first four characters of a place name then some unprintable chars.

So:
"Chin ... <snip> ... COMP"

In MAP.DF, in that position you instead see "P800".
In SOUND2.DF, in that position you instead see "XXXX" which is interesting because "XXXX" is also used in BOSCO.DF to mark the start of text used for the Cemetery Game.

BOSCO.DF: 0x9488A5
"XXXX ... <snip> ... The %s\14n| were a knock knock knocking"

So therefore I believe that COMP must appear at the beginning of a section of data. So "Chin ... <snip> ... COMP" could be the beginning of the section of (perhaps compressed) data for China in the Pirate Ship game.

I've also tried to decompile 4G.EXE using ghidra and saw calls to win32 API functions, but wasn't able to find where the DF files are decompressed after being opened with _lopen().

What I haven't tried is to try interpreting each set of four (4) bytes in MAP.DF, say, as a hexadecimal colour.

[khafaz]

Using Robert Mazur's raw pixel viewer, I created the following visualizations of the DF files:

BOSCO.DF



ISLAND.DF


MAP.DF


SOUND.DF


SOUND2.DF


TEXT.DF