SKEL (File Format)

The SKEL format is used to store animation skeletons in Tropical Freeze.

To do: This format is near identical to DKCR's CINF format, so the article should be renamed + DKCR differences should be noted

This file format needs a lot of research Structure is known, but most data is unknown.

Format

Type	Count	Name	Notes
Form Descriptor	1	SKEL Form Descriptor	Data type is SKEL
u16	1	Magic	Always 0x9E22
u16	1	Version	Always 0x13
Joint Name Array	1	Joint Name Array	Array containing the name of every joint in the skeleton.
u16	1	Unknown Count A	Matches the joint name count
u16	1	Unknown Count B	Matches the Skel Map size
u16	1	Unknown Count C
u16	1	Unknown Count D
u16	1	Unknown Count E
bool	1	Has Skeleton Map?	If false, the Skeleton Map is not present.
Skeleton Map	1	Skeleton Map	Only present if Has Skeleton Map? is true.
bool	1	Has Animation Attribute Data?	If false, the Animation Attribute Data is not present.
Animation Attribute Data	1	Animation Attribute Data	Only present if Has Animation Attribute Data? is true.
u8	Unknown Count B	Unknown
u8	Unknown Count C	Unknown
u8	Unknown Count A	Unknown
u8	Unknown Count E	Unknown
u32	Unknown Count D	Unknown
Coords	Unknown Count B	Unknown	Coordinates array (likely initial bone transforms)
Skeleton Joint Set	Unknown Count D	Skeleton Joint Set
Skeleton Set Fragment Data	1	Skeleton Set Fragment Data

Joint Name Array

Type	Count	Name	Notes
u32	1	Unknown	If non-zero, no names are present.
u32	1	Joint Name Count	Count of joint names in the array.
Joint Name	Joint Name Count	Joint Name Array	Array of joint names.
u32	1	Unknown

Joint Name

Type	Count	Name	Notes
u32	1	Name Size
char	Name Size	Name	Zero-terminated

Skeleton Map

Type	Count	Name	Notes
u16	1	Unknown Count A
u8	1	Unknown Count B
u8	1	Unknown Count C
u8	Unknown Count A	Unknown
u16	Unknown Count A × 2	Unknown
u32	Unknown Count B	Unknown
u16	Unknown Count C	Unknown
u32	1	Unknown

Animation Attribute Data

Type	Count	Name	Notes
bool	1	Has Visibility Group Name Array?	Indicates whether the Visibility Group Name Array is present.
Joint Name Array	1	Visibility Group Name Array	Only present if Has Visibility Group Name Array? is true.
bool	1	Has Animation Attribute Info Data?	Indicates whether the Animation Attribute Info Data is present.
Animation Attribute Info Data	1	Animation Attribute Info Data	Only present if Has Animation Attribute Info Data? is true.

Animation Attribute Info Data

Type	Count	Name	Notes
Joint Name Array	1	Unknown Name Array
u32	1	Animation Attribute Info Count	Count of Animation Attribute Info elements in the next array.
Animation Attribute Info	Animation Attribute Info Count	Animation Attribute Info Array

Animation Attribute Info

Offset	Type	Count	Name	Notes
0x0	u32	1	Unknown	Must be 1, otherwise the following floats aren't present
0x4	float	1	Unknown
0x8	float	1	Unknown
0xC	End of Animation Attribute Info

Coords

Offset	Type	Count	Name	Notes
0x00	Quaternion	1	Unknown	Likely bone orientation
0x10	Vector3f	1	Unknown	Likely bone scale (it's usually 1,1,1)
0x1C	Vector3f	1	Unknown	Likely bone position
0x28	End of Coords

Skeleton Joint Set

Type	Count	Name	Notes
u32	1	Unknown
u32	1	Unknown Count
u32	8	Unknown
u8	Unknown Count	Unknown

Skeleton Set Fragment Data

Type	Count	Name	Notes
u32	1	Unknown Count
u8	Unknown Count B	Unknown	This uses the count value from the base skeleton data
Unknown Struct	Unknown Count	Unknown

Unknown Struct

Offset	Type	Count	Name	Notes
0x00	u32	1	Unknown
0x04	u32	8	Unknown
0x24	End of Unknown Struct