02-11-2023, 01:38 AM
As you may all know, Metroid Prime Remaster has released, and with it, an amazing assortment of new assets. Now, I have the full Trilogy ripped already, but this release is a godsend to my aching hand trying to manually clean up the messy low resolution textures and the low poly models for otherwise great assets.
Anywho, the issue arises in that it's just released and there's little to no information (that I personally could find) regarding the specifics of the file formats Retro used for their Switch release using their proprietary RUDE engine.
Now, I've read that plenty of Switch games have their data in .pak format, but commonly used in Unreal Engine and can then be unpacked using their tools. But I haven't been so lucky, obviously. Metroid Prime Remaster isn't UE.
So at the moment, I'm stuck on this part of the ripping process. And I should mention, every extracted file is .pak, save for 1 single .arc file for materials. And just in case, I tried changing the file type to .zip and have also used 7zip to try opening it as an archive and was left disappointed. I did extract the game twice 2 different ways and got exactly the same output files, once using a 3rd party unpacker for .nsp and once using Ryujinx. Maybe there's another way that I missed; I'm not exactly good at this sort of thing, let alone knowing what I'm doing outside text telling me what steps to do.
I was hoping to try something like Ninja Ripper to intercept the data after it gets unpacked by an emulator to be rendered, but of course, incompatible with Switch emulators.
So I'm asking if anyone here knows how I can proceed from here, if I can, or if they would be so kind as to be a legendary savior who cracks the enigma code of this unholy .pak.
PS: I'm not sure if I'm allowed, but if someone does have the capability to analyze .pak files or a way to unpack proprietary packed files like from custom engines, I could provide a small sample from one of the folders (though, if you have the game file already, it's really a 5 minute process to get as far as I have)
PSS: Ideally, the final format I'm hoping to reach is something usable in Blender, like FBX so materials can stay with their models, but I suppose beggars can't be choosers since not everything can be so nice and clean like how Metaforce was with Trilogy
Thanks.
Update: Looking through hex editor, I can definitely tell the .pak files contain similar files as the original Metroid Prime (CMDL and TXTR for models and texture data). I only looked at some of the smaller files that looked like they might be connection rooms (some of the hex has "room" specified as well). This is similar to how the original game did it with entire model files for whole rooms.
As for the signature, I personally can't tie the signature to anything online for reference on what could be used to unpack it. The signature seems to be 52 46 52 4D, or RFRM, and each file has 3 more trailing bytes that aren't the same. All of them also have "Pack" specified in the same spot below the headers. And all of the large main-level .paks all have "Data" at the bottom every couple lines of hex. So I've pretty much gathered as much as a signature I can't tie to anything easily, and the fact that the .paks do, indeed, contain the models and textures in their correct formats. But unfortunately, I'm not smart enough to do anything meaningful with this info.
Update 2: While I haven't made progress on unpacking these .pak files, I have found a very useful resource specifically documenting Retro Studios' PAK files for their older games, Prime 1 and 2 (which I think was stated to have been used for Donkey Kong as well). Prime 1 seems to have used zlib based on the header, and Prime 2 LZO1X-999. The files inside the .pak were also duplicated depending on loading need to help reduce load times. While this information is very useful, Metaforce and other tools haven't been updated in quite awhile, and I still have no understanding of how to analyze these .pak files to check what kind of compression they use.
Update 3: Seems like it's definitely not a simple job to unpack these .pak files, so I'm officially dropping my search for ways to do it. Fortunately, a lot of people over in the Metaforce community are working hard on it as I type this, and were already on it before I even made a post. Unfortunately, progress doesn't seem even close to getting any clean models and textures out for use in tools like Blender. Seems these will take some fine reverse engineering skills to get through, and that's something I don't have.
Anywho, the issue arises in that it's just released and there's little to no information (that I personally could find) regarding the specifics of the file formats Retro used for their Switch release using their proprietary RUDE engine.
Now, I've read that plenty of Switch games have their data in .pak format, but commonly used in Unreal Engine and can then be unpacked using their tools. But I haven't been so lucky, obviously. Metroid Prime Remaster isn't UE.
So at the moment, I'm stuck on this part of the ripping process. And I should mention, every extracted file is .pak, save for 1 single .arc file for materials. And just in case, I tried changing the file type to .zip and have also used 7zip to try opening it as an archive and was left disappointed. I did extract the game twice 2 different ways and got exactly the same output files, once using a 3rd party unpacker for .nsp and once using Ryujinx. Maybe there's another way that I missed; I'm not exactly good at this sort of thing, let alone knowing what I'm doing outside text telling me what steps to do.
I was hoping to try something like Ninja Ripper to intercept the data after it gets unpacked by an emulator to be rendered, but of course, incompatible with Switch emulators.
So I'm asking if anyone here knows how I can proceed from here, if I can, or if they would be so kind as to be a legendary savior who cracks the enigma code of this unholy .pak.
PS: I'm not sure if I'm allowed, but if someone does have the capability to analyze .pak files or a way to unpack proprietary packed files like from custom engines, I could provide a small sample from one of the folders (though, if you have the game file already, it's really a 5 minute process to get as far as I have)
PSS: Ideally, the final format I'm hoping to reach is something usable in Blender, like FBX so materials can stay with their models, but I suppose beggars can't be choosers since not everything can be so nice and clean like how Metaforce was with Trilogy
Thanks.
Update: Looking through hex editor, I can definitely tell the .pak files contain similar files as the original Metroid Prime (CMDL and TXTR for models and texture data). I only looked at some of the smaller files that looked like they might be connection rooms (some of the hex has "room" specified as well). This is similar to how the original game did it with entire model files for whole rooms.
As for the signature, I personally can't tie the signature to anything online for reference on what could be used to unpack it. The signature seems to be 52 46 52 4D, or RFRM, and each file has 3 more trailing bytes that aren't the same. All of them also have "Pack" specified in the same spot below the headers. And all of the large main-level .paks all have "Data" at the bottom every couple lines of hex. So I've pretty much gathered as much as a signature I can't tie to anything easily, and the fact that the .paks do, indeed, contain the models and textures in their correct formats. But unfortunately, I'm not smart enough to do anything meaningful with this info.
Update 2: While I haven't made progress on unpacking these .pak files, I have found a very useful resource specifically documenting Retro Studios' PAK files for their older games, Prime 1 and 2 (which I think was stated to have been used for Donkey Kong as well). Prime 1 seems to have used zlib based on the header, and Prime 2 LZO1X-999. The files inside the .pak were also duplicated depending on loading need to help reduce load times. While this information is very useful, Metaforce and other tools haven't been updated in quite awhile, and I still have no understanding of how to analyze these .pak files to check what kind of compression they use.
Update 3: Seems like it's definitely not a simple job to unpack these .pak files, so I'm officially dropping my search for ways to do it. Fortunately, a lot of people over in the Metaforce community are working hard on it as I type this, and were already on it before I even made a post. Unfortunately, progress doesn't seem even close to getting any clean models and textures out for use in tools like Blender. Seems these will take some fine reverse engineering skills to get through, and that's something I don't have.