FF8/FileFormat DAT

By Mirex, JWP, random_npc and myst6re. Edit: We now know the animation and skeleton- see https://github.com/MaKiPL/OpenVIII/blob/4ac151daad7cd1475eb0694dd0715bc35d7a4b39/FF8/debug_battleDat.cs

Header

DAT file is divided into 11 sections (except for c0m127.dat, which contains only 2 sections : 7th and 8th).

Offset	Length	Description
0	4 bytes	Number of sections (always =11, except for c0m127.dat)
4	nbSections * 4 bytes	Section Positions
4 + nbSections * 4	4 bytes	File size

Section 1: Skeleton

Offset	Length	Description
0	2 bytes	Number of bones
2	6 bytes	Unknown
8	s16f (divide by 4096f)	scaleX
10	s16f (divide by 4096f)	scale -Z
12	s16f (divide by 4096f)	scale Y
14	2 bytes	Unknown
16	Number of bones * 48 bytes	Bones

Bone struct

Offset	Length	Description
0	2 bytes	Parent id
2	s16f (divide by 4096f)	Bone size (?)
4	s16f (divide by 4096f)	unknown, multiplied by 360f
6	s16f (divide by 4096f)	unknown, multiplied by 360f
8	s16f (divide by 4096f)	unknown, multiplied by 360f
10	s16f (divide by 4096f)	unknown
12	s16f (divide by 4096f)	unknown
14	s16f (divide by 4096f)	unknown
16	28 bytes	Unknown (often empty)

Section 2: Model geometry

Header (data sub table)

Offset	Length	Description
0	4 bytes	Number of objects
4	nbObjects * 4 bytes	Object Positions
4 + nbObjects * 4	Varies	Object Data (see below)
Varies	4 bytes	Total count of vertices

Object Data

Offset	Length	Description
0	2 bytes	Number of Vertices Data
2	Varies * NbVerticesData	Vertices Data (see below)
Varies	4 - (absolutePosition % 4)	Padding (0x00)
Varies	2 bytes	Num triangles
Varies	2 bytes	Num quads
Varies	8 bytes	Always empty
Varies	numTriangles * 16 bytes	Triangles
Varies	numQuads * 20 bytes	Quads

Vertice Data

Offset	Length	Description
0	2 bytes	Bone id
2	2 bytes	Number of vertices
4	nbVertices * 6 bytes	Vertices (nbVertices * 3 shorts)

Useful structures

struct vertice {
     sint16	x, y, z;
};

(sizeof = 6)

struct triangle {
     uint16	vertex_indexes[3]; // vertex_indexes[0] &= 0xFFF, other bits are unknown
     uint8	texCoords1[2];
     uint8	texCoords2[2];
     uint16	textureID_related;
     uint8	texCoords3[2];
     uint16	u; // textureID_related2
};

(sizeof = 16)

struct quad {
     uint16	vertex_indexes[4]; // vertex_indexes[0] &= 0xFFF, other bits are unknown
     uint8	texCoords1[2];
     uint16	textureID_related;
     uint8	texCoords2[2];
     uint16	u; // textureID_related2
     uint8	texCoords3[2];
     uint8	texCoords4[2];
};

(sizeof = 20)

Section 3: Model animation

Header (data sub table)

Offset	Length	Description
0	4 bytes	Number of animations
4	nbAnimations * 4 bytes	Animations Positions

Animation

Offset	Length	Description
0	1 byte	Number of frames
1	Varies	Unknown

Section 4: Unknown

Optional section, often empty.

Section 5: Unknown

Unknown sequences.

Header

Offset	Length	Description
0	2 bytes	Number of sequences
2	nbSequences * 2 bytes	Sequences Positions

Section 6: unknown

Can be empty.

Section 7: Informations & stats

Offset	Length	Description
0	24 bytes	Monster name
24	4 bytes	HP values
28	4 bytes	Str values
32	4 bytes	Vit values
36	4 bytes	Mag values
40	4 bytes	Spr values
44	4 bytes	Spd values
48	4 bytes	Eva values
52	16*4 bytes	Abilities, low level
116	16*4 bytes	Abilities, med level
180	16*4 bytes	Abilities, high level
244	1 byte	Med level start
245	1 byte	High level start
246	1 byte	Unknown (flags, 3 bits used)
247	1 byte	[LSB] Zombie / Fly / zz1 / zz2 / zz3 / Auto-Reflect / Auto-Shell / Auto-Protect [MSB]
248	3 bytes	Cards (low/med/high)
251	3 bytes	Devour (low/med/high)
254	1 byte	[LSB] zz1 / zz2 / unused / unused / unused / unused / Diablos missed / Always obtains card [MSB]
255	1 byte	Unknown (flags, 4 bits used)
256	2 bytes	Extra EXP
258	2 bytes	EXP
260	8 bytes	Draw (low)
268	8 bytes	Draw (med)
276	8 bytes	Draw (high)
284	8 bytes	Mug (low)
292	8 bytes	Mug (med)
300	8 bytes	Mug (high)
308	8 bytes	Drop (low)
316	8 bytes	Drop (med)
324	8 bytes	Drop (high)
332	1 byte	Mug rate
333	1 byte	Drop rate
334	1 byte	Padding (0x00)
335	1 byte	APs
336	16 bytes	Unknown
352	8 bytes	Elemental resistance (Fire, Ice, Thunder, Earth, Poison, Wind, Water, Holy)
360	20 bytes	Mental resistance (Death, Poison, Petrify, Darkness, Silence, Beserk, Zombie, Sleep, Haste, Slow, Stop, Regen, Reflect, Doom, Slow Petrify, Float, Confuse, Drain, Expulsion, ???)

Abilities

typedef struct {
    uint8 kernel_id;
    uint8 unknown;
    uint16 ability_id;
}

kernel_id is the used table in kernel.bin. May be 0x02 (= magic), 0x04 (= item) or 0x08 (= monster ability). ability_id is the ability in the selected kernel table.

Draw/mug/drop

typedef struct {
    uint8 id_1; // magic_id for draw, item_id for mug & drop
    uint8 qty_1; // quantities are always 0 for draw
    uint8 id_2;
    uint8 qty_2;
    uint8 id_3;
    uint8 qty_3;
    uint8 id_4;
    uint8 qty_4;
}

Section 8: Battle scripts/AI

Offset	Length	Description
0	4 bytes	Number of sub-sections
4	4 bytes	Offset to AI sub-section
8	4 bytes	Offset to text offsets
12	4 bytes	Offset to text sub-section

AI

Offset	Length	Description
0	4 bytes	Offset to init code
4	4 bytes	Offset to code executed at ennemy's turn
8	4 bytes	Offset to counterattack code
12	4 bytes	Offset to death code
16	4 bytes	Unknown offset

Texts

Text offsets is a list of text positions (2 bytes each) in the text sub-section.

Section 9: Sounds

Contains AKAO sequences (can be empty).

Offset	Length	Description
0	2 bytes	Number of AKAOs
2	nbAKAOs * 2 bytes	AKAOs Positions
2 + nbAKAOs * 2	2 bytes	End of section 9
4 + nbAKAOs * 2	Varies * nbAKAOs	AKAOs

Section 10: Sounds/Unknown

Contains AKAO sequence + unknown data (can be empty).

Section 11: Textures

Contains some TIMs with size 128x128 (8bit paletized).

Offset	Length	Description
0	4 bytes	Number of TIMs
4	nbTIMs * 4 bytes	TIMs Positions
4 + nbTIMs * 4	4 bytes	End of file
8 + nbTIMs * 4	Varies * nbTIMs	TIMs