FF8/FileFormat MCH

Authors: Koral, Vehek

MCH Field Character Models

Each MCH file contains a skinned-animated model representing a character on the field or world Maps. There appear to be multiple files of the same character representing differnt Level of Details.

They usually contain multiple TIM textures (standard PSX textures), mesh geometry, bones, skeleton heirarchy information and skinning information. The whereabouts of the Bone Animation data is currently unknown.

Accessing MCH Files

todo

MCH File Structure

Header

0x100 bytes [256 bytes]

    DWORD: Offsets to multiple Texture-Data
        Start: 0x00
        Parse DWORDS until read value: 0xFFFFFFFF

    DWORD: Offset to Model Data
    

Texture-Data

TIM format

(for each Texture)

    Standard [TIM] format textures

Model-Data

Offset	Length	Description
0x00	4 bytes	Number of Skeleton Bones
0x04	4 bytes	Number of Vertices
0x08	4 bytes	Number of texture animations
0x0C	4 bytes	Number of Faces
0x10	4 bytes	Number of Unknown data
0x14	4 bytes	Number of Skin objects
0x18	4 bytes	Unknown
0x1C	2 bytes	Triangle count
0x1E	2 bytes	Quad count
0x20	32 bytes	Unknown

    Skeleton Data: 0x40 bytes per bone, recurse through number of bones dictated in Header
    (for each bone)

        SHORT: parent bone (1-based)
        SHORT:   (unknown)
        DWORD:   (unknown)
        SHORT: bone length
        DWORD * 15:   (unknown)
          

    Vertex Data:
    (for each vertex)

        SHORT * 3: Vertex XYZ Position
        SHORT:   (unknown)
        DWORD * 4:   (unknown)
          

    Texture-animations Data:
struct
{
	byte unknown
	byte total_textures?
	byte unknown
	byte uSize
	byte vSize
	byte replacement_section_count
	UV_pair original_area_coords
	byte unknown[2]
	UV_pair replacement_coords[replacement_section_count]
}

    Face Data:
    (for each face)

        DWORD:   (unknown)
        BYTE * 3:    (unknown)
        BYTE:  Polygon Type [0x2d = Quad, 0x25 = Triangle]
        SHORT: When bit 0x04 set, face has semi-transparency
        SHORT:    (unknown)
        DWORD:   (unknown)
        SHORT * 4: Indices per Face-Vertex
        SHORT * 4:   (unknown)
        BYTE * 4 * 4: Vertex Colour (RGBA) per Face-Vertex
        BYTE * 2 * 4: Vertex UV, (1st byte U, 2nd byte V) per Face-Vertex
        DWORD * 12:  (unknown)
  

    Unknown Data, Seems to split up the skin-objects, triangles, and quads:
struct
{
	uint16 start_skinobject_index
	uint16 skinobject_count
	byte unknown[12]
	uint16 start_triangle_index
	uint16 triangle_count
	uint16 start_quad_index
	uint16 quad_count
	byte unknown2[8]
}

    Skin-Object Data: 
    (for each skin-object)

        SHORT: Bone ID (1-based)
        SHORT:   (unknown)
        SHORT: index of first vertex
        SHORT: number of vertices
        

todo: notes on skinning, animation data

MCH Model File List

todo