MREA (File Format)
The .MREA file format is used to define areas in Metroid Prime and Donkey Kong Country Returns. MREA files are broken up into many sections, and each section serves a specific purpose. However for the sake of brevity this article will only cover each revision of the MREA header.
Universal Header
This header is shared between Metroid Prime and Donkey Kong Country, and is fairly straight forward.
| Offset | Size | Description |
|---|---|---|
| 0x0 | 4 | Magic Number 0xDEADBEEF |
| 0x4 | 4 | File Version See below |
| 0x8 | 48 | Transformation Matrix The position of the area in world-space |
| 0x38 | 4 | Mesh Count |
| 0x3C | 4 | SCLY Count Note: Not present in Metroid Prime 1 |
| 0x40 | 4 | Section Count |
| Version | Game |
|---|---|
| 15 | Metroid Prime 1 |
| 25 | Metroid Prime 2 |
| 30 | Metroid Prime 3 |
| 32 | Donkey Kong Country Returns |
Metroid Prime Section Numbers
Immediately following the header each section in an MREA is given it's own number, the following is the order in which they appear:
| Description |
|---|
| Materials |
| SCLY |
| SCGN Note: Not present in Metroid Prime 1 |
| Collision |
| Unknown |
| Lights |
| VISI |
| PATH |
| AROT |
| PTLA Note: Not present in Metroid Prime 1 |
| EGMC Note: Not present in Metroid Prime 1 |
Metroid Prime 3 & Donkey Kong Header
Metroid Prime 3 and Donkey Kong Country Returns share the same header, also Metroid Prime 2 contains the Compressed Block Count present in this header as well.
| Offset | Size | Description | ||
|---|---|---|---|---|
| 0x0 | 4 | Compressed Block Count Note: Present in Metroid Prime 2 | 0x4 | Section Number Count Note: see below |