CLSN (File Format)

The CLSN format in Donkey Kong Country: Tropical Freeze is for static collision, usually used by world geometry.

This file format is almost completely documented Collision materials need experimentation to verify structure + figure out what the different flags do

Format

Type	Count	Name	Description
Form Descriptor	1	Collision Form Descriptor	Data type is CLSN
Chunk Descriptor	1	Vertices Chunk Descriptor	Data type is VERT
u32	1	Vertex Count
vector3	Vertex Count	Vertex Data
Chunk Descriptor	1	Collision Materials Chunk Descriptor	Data type is MTRL
u32	1	Collision Material Count
Collision Material	Collision Material Count	Collision Materials	Collision materials define collision properties.
Chunk Descriptor	1	Triangles Chunk Descriptor	Data type is TRIS
u32	1	Triangle Count
Collision Triangle	Triangle Count	Triangles Array
Chunk Descriptor	1	Tree Chunk Descriptor	Data type is TREE
u32	1	Leaf Node Count
Tree Leaf Node	Leaf Node Count	Leaf Node Array
End of file

Collision Material

Offset	Type	Count	Name	Description
0x0	u32	1	Unknown
0x4	u32	1	Unknown
0x8	u32	1	Unknown
0xC	u32	1	Unknown
0x10	u32	1	Unknown
0x14	End of collision material

Collision Triangle

Offset	Type	Count	Name	Description
0x0	u32	3	Vertex Indices
0xC	u16	1	Collision Material Index
0xE	u16	1	Unknown	Always 0? The game actually does read and store it, so it may not just be padding.
0x10	End of triangle

Tree Leaf Node

Offset	Type	Count	Name	Description
0x0	vector3	2	Axis-Aligned Bounding Box	Represented by a pair of points where point 1 is min and point 2 is max.
0x18	u32	1	Unknown
0x1C	u32	1	Unknown
0x20	u32	1	Unknown
0x24	End of leaf node