BMD and BDL (File Format)
BMD and BDL are two file formats used by a wide variety of Nintendo games between the GameCube and Wii.
File Header
The file begins with the header of 0x10 bytes. BDL Includes an extra section (MDL3) that BMD does not. The structure is the same as for BCK & JPA files (All lengths are in Hexadecimal):
| Offset | Size | Description | |
|---|---|---|---|
| 0x00 | 8 | File identifier: 'J3D2bmd3' for BMD and 'J3D2bdl4' for BDL in ASCII. | |
| 0x08 | 4 | Length of file in bytes. | |
| 0x0c | 4 | Number of sections in the file (08 in BMD & 09 in BDL) | |
| 0x10 | 4 | 'SVR3' in ASCII. | |
| 0x14 | 0C | Consists only of FF (Padding?) | |
| End of header | |||
Sections
BMD and BDL contain mostly the same sections, with the exception of the MDL3 section that appears only within BDL files.
INF1
The INF1 section contains Model Information.
| Offset | Size | Description |
|---|---|---|
| 0x00 | 2 | Section name: 'INF1' in ASCII. |
| 0x04 | 4 | Length of section in bytes. |
| 0x08 | 2 | Unknown model setting (very similar to MDL0), 01 for BMD & 00 for BDL. |
| 0x0a | 4 | Unknown model setting, always FFFF0000. |
| 0x0c | 4 | Unknown model setting, seen to be anywhere from 0001 - 0030. |
| 0x10 | 4 | Number of coordinates in VTX1 section. |
| 0x14 | 4 | Offset location relative to beginning of section (After the length of section, typically location 0x18). |
| 0x18 (O = The offset) | 2 | Unknown setting (Always 00 10). |
The next part of the INF1 section describes the scene graph of the file, it controls what references what. It starts immediately after 0x18 in the INF1 section. There can be many of these and they go in order:
| Offset | Size | Description |
|---|---|---|
| 0x00 + O | 4 | Unknown. |
| 0x04 + O | 4 | Unknown. |
| 0x08 + O | 4 | Unknown. |
| 0x0a + O | 4 | Unknown. |
| 0x0e + O (O2 = This Offset) | 4 | Unknown. |
The end of this section:
| Offset | Size | Description | |
|---|---|---|---|
| 0x00 + O2 | O2 - Start of VTX1 Section | Attempts to spell '......This is padding data to align' until the beginning of the VTX1 section in ASCII. | |
| End of INF1 Section | |||
VTX1
The VTX1 sections stores the vertex arrays for positions, colors, normals and texture coordinates. Additionally, it stores the data format in which these arrays are stored.
| Offset | Size | Description | |
|---|---|---|---|
| 0x00 | 4 | Section name: 'VTX1' in ASCII. | |
| 0x04 | 4 | Size of section in bytes. | |
| 0x08 | 4 | Offset location of the array data. | |
| 0x0c | 4 | Offset relative to the start of the 'VTX1' section (Always 0A if VTX1 section begins 0xFF). | |
| End of section header, beginning of array format | |||
The next section of the VTX1 section describes the array format, this section can be used many times.
| Offset | Size | Description | |
|---|---|---|---|
| 0x00 | 4 | ArrayType. (See VTX1 Array Types, the last array always seems to have 0x000000ff here) | |
| 0x04 | 4 | ComponentCount. Effects DataType, 00 = Component Type 1, 01 = Component Type 2 | |
| 0x08 | 4 | DataType. (See VTX1 Component Types) | |
| 0x09 | 1 | Position of decimal point, has only been seen to be 00, 07, 08, 0b & 0e. | |
| 0x0a | 1 | Unknown. Always FF | |
| 0x0b | 2 | Unknown. Always FF FF | |
| End of array format | |||
If there are five arrays or less, then immediately after the last array this will appear, and likewise if it exceeds five then it will not:
| Size | Description |
|---|---|
| 0A | Spells 'This is padding ' in ASCII |
From here the VTX1 sections stores Vertex Data, until the beginning of the next section.
EVP1
This section is what contains the weight data for vertex skinning.
| Offset | Size | Description |
|---|---|---|
| 0x00 | 4 | Section name: 'EVP1' in ASCII. |
| 0x04 | 4 | Size of section in bytes. |
| 0x06 | 2 | What it should count (See EVP1 Count Index |
| 0x08 | 2 | Padding (FF) |
Format Values
Here are specific values and their meanings are listed for various sections.
VTX1
Known values for VTX1.
ArrayType
| Value | Reference | Description |
|---|---|---|
| 0x00 | 'POSITION_MATRIX_INDEX' | |
| 0x01 | 'TEX0_MATRIX_INDEX' | |
| 0x02 | 'TEX1_MATRIX_INDEX' | |
| 0x03 | 'TEX2_MATRIX_INDEX' | |
| 0x04 | 'TEX3_MATRIX_INDEX' | |
| 0x05 | 'TEX4_MATRIX_INDEX' | |
| 0x06 | 'TEX5_MATRIX_INDEX' | |
| 0x07 | 'TEX6_MATRIX_INDEX' | |
| 0x08 | 'TEX7_MATRIX_INDEX' | |
| 0x09 | 'POSITION' | Texture position |
| 0x0a | 'NORMAL' | This effects the direction of the normals |
| 0x0b | 'COLOR0' | Vertex Color Channel 1 |
| 0x0c | 'COLOR1' | Vertex Color Channel 2 |
| 0x0d | 'TEX0' | |
| 0x0e | 'TEX1' | |
| 0x0f | 'TEX2' | |
| 0x10 | 'TEX3' | |
| 0x11 | 'TEX4' | |
| 0x12 | 'TEX5' | |
| 0x13 | 'TEX6' | |
| 0x14 | 'TEX7' | |
| 0x15 | 'POSITION_MATRIX_ARRAY' | |
| 0x16 | 'NORMAL_MATRIX_ARRAY' | |
| 0x17 | 'TEXTURE_MATRIX_ARRAY' | |
| 0x18 | 'LIT_MATRIX_ARRAY' | |
| 0x19 | 'NORMAL_BINORMAL_TANGENT' | |
| 0x1a | 'MAX_ATTR' | |
| 0xff | 'NULL_ATTR' |
CompType
Type 1
This may be used in DataType if ComponentType is set to 00:
| Value | Reference | Description |
|---|---|---|
| 0x00 | 'U8' | |
| 0x01 | 'S8' | |
| 0x02 | 'U16' | |
| 0x03 | 'S16' | |
| 0x04 | 'F32' |
Type 2
This may be used in DataType if ComponentType is set to 01:
| Value | Reference | Description |
|---|---|---|
| 0x00 | 'RGB565' | |
| 0x01 | 'RGB8' | |
| 0x02 | 'RGBX8' | |
| 0x03 | 'RGBA4' | |
| 0x04 | 'RGBA6' | |
| 0x05 | 'RGBA8' |
EVP1
Known values for EVP1.
Count
| Value | Description |
|---|---|
| 0x00 | Counts each bone |
| 0x01 | |
| 0x02 | |
| 0x01 |