Difference between revisions of "MREA (Metroid Prime 2)"
(some data has to be repeated between articles with this setup but it's probably worth it for the clean separation of differences between versions of the format.) |
(No difference)
|
Revision as of 08:59, 28 January 2015
The MREA format defines areas (rooms) in Metroid Prime 2. It serves the same purpose as the MREA files from Prime 1, but in Echoes it was updated with new features, including some new data sections and the ability to compress most of the data in the file.
To do: Rest of the article needs to be written. There's a lot known about this format that should be documented. |
Contents
Format
Like CMDL, MREA files are split up into a number of 32-byte aligned sections. Every section both starts and ends on a 32-byte boundary. These are used to separate different parts of the file; different types of sections typically indicate different sets of data. The header declares the section count and the size of each one; using these is the only way to navigate the file.
Offset | Size | Description |
---|---|---|
0x0 | 4 | Magic; always 0xDEADBEEF |
0x4 | 4 | Version; see hub article |
0x8 | 4 × 12 | Transform matrix |
0x38 | 4 | Mesh count |
0x3C | 4 | SCLY layer count |
0x40 | 4 | Section count (SC) |
0x44 | 4 | Geometry section number (starts on materials) |
0x48 | 4 | SCLY section number |
0x4C | 4 | SCGN section number |
0x50 | 4 | Collision section number |
0x54 | 4 | Unknown section number |
0x58 | 4 | Lights section number |
0x5C | 4 | Empty section number |
0x60 | 4 | PATH section number |
0x64 | 4 | FFFFFFFF section number |
0x68 | 4 | Unknown section 2 number |
0x6C | 4 | EGMC section number |
0x70 | 4 | Compressed cluster count |
0x74 | 0xC | Padding |
0x80 | 4 × SC | Section sizes |
Pad to 32 bytes before compressed cluster definitions begins |
Following the section sizes comes an array defining the file's compressed cluster. Each definition is 0x10 bytes and is formatted like this:
{{ class="wikitable" ! Offset ! Size ! Description |- | 0x0 | 4 | Buffer size (usually 0x120 bytes bigger than uncompressed size) |- | 0x4 | 4 | Uncompressed size |- | 0x8 | 4 | Compressed size (if 0, that indicates an uncompressed cluster) |- | 0xC | 4 | Section count (the number of regular sections contained in this cluster) |- | 0x10 | colspan=2 | Cluster definition end |}