Add Reverse Engineering - Sound

Reverse Engineering - Sound.-.md

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+## General
+
+Sounds, both sound effects and music, seem to be split across multiple file types. So far, we know about three:
+
+- [`.wwise_bank`](File+Type+-+Wwise+Bank.-): A full Wwise Soundbank that contains an arbitrary amount of sound and music events, as well as all the extra data to use them
+- [`.wwise_event`](File+Type+-+Wwise+Event.-): A small soundbank that contains only a single HIRC event, though it may contain multiple `.wem` files.
+- [`.wwise_stream`](File+Type+-+Wwise+Stream.-): A marker pointing to a file in `data/` containing a single, raw `.wem` file (based on the `RIFF` header).
+
+The relationship between these is still unknown.
+There are only two `.wwise_bank` files in total, so these must be setting up the entire sound environment for the game. I would expect to find some form of link/pointer from these banks to the `.wwise_event` and `.wwise_stream` files.
+
+## Decompilation
+
+Decompilation should be possible with the existing information. The Wwise formats are well known across modding scenes in other games, and VT2's unpacker can serve as prior art as well.
+
+## Compilation
+
+Until the relationship between the different file types is figured out, we will be limited. But what should already be possible is to generate `.wem` files and insert them into existing files, which would allow replacing existing sounds. Though it would require a lot of manual effort to map files to the in-game sound events.
+
+As such, a tool would need to be written that can read a community-maintained mapping list from sound event names to murmur hashes of file names and can use that to replace `.wem` files in binary.