Megaman Legends 2 Research Thread (PSP) Jun 26, 2020 11:40:35 GMT -5 Rockman Striker and RyanLEO like this
Post by kion on Jun 26, 2020 11:40:35 GMT -5
I've been wanting to take another look at Megaman Legends 2, and my schedule finally opened up a little bit to start to poke at the files. With the PSX version of the game, there were two issues with the textures. One is that they we compressed. And second was these was no easy way to try and match up textures with meshes as everything was an index in the framebuffer. And I think what makes that issue worse is that with the limited framebuffer means that the game has to load in more textures which cause the texture indexes to overlap. So I think it's worth taking a look into the PSP version to see if there's any advantages to working with this version of the game. Hopefully we'll have normal TIM or GIM files to work with, but we'll have to dig in to find out.
So we can start with some simple observations for the file layout. In the Top level folder which simply contains the file "umd_data.bin" and the folder "psp_game".
When we go into the "psp_game" folder we get a few png images for PSP menu. We also have two folders "sysdir" and "usrdir". To save ourselves sometime the "sysdir" seems to contain the eboot.bin file. So I'm guessing these are the elf executable for the PSP to boot from to start the game.
Getting into the "usrdir" we see a few familiar looking folders. The "common" folder contains assets that are used through out the game like the meshes for Megaman, the menu sprites and the gameover screen.The "dat" folder contains all of the information for each of the scenes. Specifically this is going to be the stage and actor data for each stage. The "e1" folder is for "Episode 1", which doesn't seem to be the original game, it seems to be 4 mini-games of content that I guess is supposed to take place between Megaman Legends 1 and Megaman Legends 2. Assuming the "e1" folder uses the same file formats as the other folders we can come back to this.
And the last two folders are "kmodule" and "module", these seem to include a bunch of ".prx" files, which I guess are probably like ".dll" files in that they're probably linked libraries. So nothing that we need to interact with directly. So that means we probably want to start by focusing our attention on "psp_game/usrdir/common" and "psp_game/usrdir/dat".