CHR File Format

Unofficial CHR File Format description

Date: 2017.01 | Version: 0.5

Glossary

GR - Ghost Recon,
GRE - Ghost Recon engine

-TODO-

Unknown variables annd const.

Table of contents

1. Introduction

2. Overview

3. Sections

3.1 File header

3.2 MaterialList section

3.3 GeometryList section

3.4 Animations data section

Appendix A.

Introduction

This document describes the structure of the CHR file format used by the GRE. The GR game CHR files are stored in "Model" folder and has an extension of ".chr".

Overview

The CHR file contains the information about game characters 3D models. This includes information about materials, textures, 3d geometry and animations data. You can create CHR files with an official developer plugin for 3DS MAX 3..5 version.

Overall file structure

The CHR file format is divided into two major sections and two signatures as shown in the CHR file structure.

Table 1. CHR file structure

№	Section	Description	Links
1	File Header	File header	see Table 2
2	BeginModel Signature	-	see Table
3	MaterialList Section	Materials and textures information	see Table 3
4	GeometryList Section	Geometry objects data	see Table 13
2	EndModel Signature	-	see Table
5	Bones Section	Animations data	see Table 27

Notes

The file header has a fixed length; the other three sections are variable in length.

Sections

File Header

The CHR header is 4 bytes long.

Table 2. File header structure

Length	Type	Description
4	DateTime	File modified date.

BeginModel Signature

Table 3. BeginModel Signature structure

Length	Type	Description	Value
4	integer	File signature length.	11
11	string	File signature string.	"BeginModel."

Notes

The file signature is unique file identifier that helps game engine to auto-detect the file type on load. Most of GR game files have there unique signatures.

MaterialList section

The MaterialList section contains information about object's materials and textures.

Table 3. MaterialList section structure

№	Section	Description	Links
1	Header		see Table 4
2	Materials subsection	Object's materials	see Table 7
3	Textures subsection	Object's textures	see Table 9

MaterialList section header

MaterialList section header is 41 bytes long. It is structured as follows:

Table 4. MaterialList header

№	Length	Type	Description	Value
1	4	integer	MaterialList section size.	variable
2	4	integer	ID	8
3	4	integer	"Version." string length. Equal to 8.	8
4	8	string	"Version." string.	"Version."
5	4	integer	Version value.	3
6	4	integer	"MaterialList." string length. Equal to 11.	13
7	13	string	"MaterialList." string.	"MaterialList."

1.1 Materials subsection

Table 5. Materials subsection structure

№	Length	Type	Description	Links
1	4	integer	Materials Count
2	variable	array	Materials Array	see Table 6

Materials Array is an array, repeated for the Object materials count. It is as follows:

Table 6. Materials Array

№	Section	Links
1	Header	see Table 7
2	Material properties	see Table 8

Materials Array Header is variable in length. It is structured as follows:

Table 7. Header

№	Length	Type	Description	Value
1	4	integer	Section size.
2	4	integer	ID value.	8
3	4	integer	"Version." string length. Equal to 8.	8
4	8	string	"Version." string.	"Version."
5	4	integer	Version value.	3
6	4	integer	Material Name string length.
7		string	Material Name string.

Table 8. Material properties

№	Length	Type	3dsMax type	Description	Value
1	4	float	integer	Opacity (0-100)	0..1
2	4	integer	integer	Faceted	0 - on, 3 - unset
Ambient Color Map values	0..1
1	4	float	integer	Red (0-255)	0..1
2	4	float	integer	Green (0-255)	0..1
3	4	float	integer	Blue (0-255)	0..1
4	4	float		Unknown constant	1
Diffuse Color Map values	0..1
1	4	float	integer	Red (0-255)	0..1
2	4	float	integer	Green (0-255)	0..1
3	4	float	integer	Blue (0-255)	0..1
4	4	float			Unknown constant
Specular Color Map values	0..1
1	4	float	integer	Red (0-255)	0..1
2	4	float	integer	Green (0-255)	0..1
3	4	float	integer	Blue (0-255)	0..1
4	4	float		Unknown constant	1
5	4	float	integer	Specular level	0..1
6	1	integer	integer	2-Side	0 - off, 1 - on

1.2 Textures subsection

Table 9. Textures subsection structure

№	Length	Type	Description	Links
1	4	integer	Textures count
2	variable	array	Textures Array List	see Table

Textures Array is an array, repeated for the Object textures count. It is as follows:

Table 10. Textures Array

№	Section	Links
1	Header	see Table 11
2	Texture properties	see Table 12

Textures Array Header is variable in length. It is structured as follows:

Table 11. Header

№	Length	Type	Description	Value
1	4	integer	Section size.
2	4	integer	ID	38
3	4	integer	"Version." string length. Equal to 8.	8
4	8	string	"Version." string.	"Version."
5	4	integer	Version value.	2
6	4	integer	Texture Name string length.
7		string	Texture Name string.

Table 12. Texture properties

№	Length	Type	3Ds Max type	Description	Value
1	1	byte		Unknown constant.	0
2	4	integer		The Length of the filename string.
3		string		Texture filename.
4	4	integer	integer	Advanced transparency type.	0 - subtractive, 2 - additive, 3 - filter
5	4	integer	integer	Tiled	1 - u tiled only, 2 - v tiled only, 3 - none
6	4	float	integer	Self-illumination (0-100)	0..1

GeometryList section

Table 13. GeometryList section structure

№	Type	Section	Links
1		Header	see Table 13
2	integer	Object Count
3	array	Objects array	see Table 14

GeometryList section header

GeometryList section header is 41 bytes long.

Table 14. GeometryList section header

Length	Type	Description	Value
4	integer	GeometryList section size.
4	integer	ID	7
4	integer	"Version." string length. Equal to 8.	8
8	string	"Version." string.	Version.
4	integer	Version value.	1
4	integer	"GeometryList." string length. Equal to 11.	11
13	string	"GeometryList." string.	GeometryList.

Objects array is an array, repeated for the Object count. It contains information about verticies coordinates, texture coordinates, face and texture indexes, normals and texture color map. Object itself it is a group of separated 3d models stored in an array.

Table 15. Objects array structure

Length	Type	Description	Links
variable		Header	see Table 16
2	integer	Unknown const	0
4	integer	Vertex Count
variable	array	Vertex array	see Table 17
4	integer	3D models count
variable	array	Models array	see Table 18

Table 16. Header

Length	Type	Description	Value
4	integer	Section size.
4	integer	ID.	4
4	integer	"Version." string length.	8
8	string	"Version." string.	"Version."
4	integer	Version value.	8
4	integer	Object Name string length.
variable	string	Object Name string.

Vertex array is an array, repeated for the Vertex Count. It contains information about verticies coordinates. It is as follows:

Table 17. Vertex array structure

Length	Type	3ds Max type	Description
4	float	float	X coordinate
4	float	float	Y coordinate
4	float	float	Z coordinate

Models array is an array, repeated for the 3D models Count. It contains information about texture coordinates, face and texture indexes, normals and color map. It is as follows:

Table 18. Models array structure

Length	Type	3ds Max type	Description	Value	Links
Properties
1	integer		Unknown const	1
1	integer	integer	DetailedDarkmap	0 - off, 1 - on
1	integer	integer	DetailTexture	0 - off, 1 - on
4	integer	integer	Index of a material
1	integer		isTextured	0 - no, 1 - yes
if isTextured > 0 then there is one more variable
4	integer	integer	Index of a texture
if isTextured > 0 and DetailTexture > 0 there is one more variable
4	integer	integer	Index of a DetailTexture
MAPs, If value is 4294967295 then it means empty value
4	integer	integer	Unknown variable
4	integer	integer	SelfIlluminationMap Index
4	integer	integer	SpecularMap Index
4	integer	integer	BumpMap Index
4	integer	integer	ReflectionMap Index
4	integer		MapCount
4	integer	integer	Faces Count
	array		Normals1	see Table 19
	array		Face indexes	see Table 20
	array		Texture indexes	see Table 21
4	integer	integer	Vertex Count
4	integer	integer	Texture Count
	array		Normals2	see Table 22
If Texture Count > 0 then there is an array of the Texture coordinates
	array		Texture coordinates	see Table 23
	array		Color map	see Table 24

Normals1 array is an array, repeated for the Face Count. It contains information about normals coordinates.

Table 19. Normals1 array

Length	3ds Max type	Type	Description
4	float	float	X coordinate
4	float	float	Y coordinate
4	float	float	Z coordinate
4	float	float	Distance from model origin to face, sign defines direction of normal vector

Face indexes array is an array, repeated for the Face Count. It contains information about face indexes of a triangle polygon.

Table 20. Face indexes array

Length	3ds Max type	Type	Description
2	integer	integer	First point index
2	integer	integer	Second point index
2	integer	integer	Third point index

Texture indexes array is an array, repeated for the Face Count. It contains information about texture indexes of a triangle polygon.

Table 21. Texture indexes array

Length	3ds Max type	Type	Description
2	integer	integer	First point index
2	integer	integer	Second point index
2	integer	integer	Third point index

??? Normals2 array is an array, repeated for the Vertex Count. It is another array that contains information about normals coordinates.

Table 22. Normals2 array

Length	3ds Max type	Type	Description
4	float	float	X
4	float	float	Y
4	float	float	Z

Texture coordinates array is an array, repeated for the (Vertex Count)*(TextureCount). It contains information about Texture coordinates.

Table 23. Texture coordinates array

Length	3ds Max type	Type	Description
4	float	float	U
4	float	float	V

Color map array is an array, repeated for the Vertex Count. It contains information about color map, which applied on a faces without a texture assigned.

Table 24. Color map array

№	Length	Type	3Ds Max type	Description	Value
1	4	float	integer	Red (0..255)	0..1
2	4	float	integer	Green (0..255)	0..1
3	4	float	integer	Blue (0..255)	0..1
4	4	float	integer	Unknown const	1

The sections is ends with the unknown constant equal 0.

Table 25. Number

Length	Type	Value
4	UINT	Unknown constant

EndModel Signature

EndModel signature is 13 bytes long.

Table 26. Color map array

№	Length	Description
1	4	EndModel signature length. Equal to 9.
2	9	EndModel signature: always equal to 'EndModel'.

Bones section

Table 27. Bones section structure

№	Section	Links
1	Header	see Table 28
2	Bones array	see Table 30
3	Weight table	see Table 30

Table 28. Header

№	Length	Type	Description	Value
1	4	integer	ID	37
2	4	integer	Version string length	8
3		string	Version string	"Version."
4	4	integer	Version value	5
5	4	integer	Bone name string length
6		string	Bone name string	see Table 29

Table 29. Default bones names

**№ **	Name
1	SpineRoot
2	SpineLow
3	SpineMid
4	SpineTop
5	Neck2
6	Neck
7	RBicep
8	Head
9	RForearm
10	RHand
11	LBicep
12	LForearm
13	LHand
14	RThigh
15	RCalf
16	RFoot
17	RToe
18	LThigh
19	LCalf
20	LFoot
21	LToe

Bones array is an array, repeated for the Bones count (21). It contains information about animation bones. It is as follows:

Table 30. Bones array structure

№	Length	Type	Description	Value
Position coordinates (x,y,z)
1	4	float	X
2	4	float	Y
3	4	float	Z
Rotation coordinates (quats)
1	4	float	X
2	4	float	Y
3	4	float	Z
4	4	float	Angle
1	4	integer	Unknown constant	0
2	4	integer	Bone connections	0..3

Weight table contains information about character model vertexes weights. It is as follows:

Table 31. Weight table structure

№	Length	Type	Description	Links
1	4		Header	see Table 32
2	4	integer	Vertexes count	see Table 33
3	4	array	Weights array	see Table 33

Table 32. Header

№	Length	Type	Description	Value
1	4	integer	String length
2		string	Modifier name string
3	4	integer	Unknown constant	1
4	4	integer	Body name string length
5		string	Body name string

Vertex weights array is an array, repeated for the Vertexes count. It is as follows:

Table 33. Vertex weights array

№	Length	Type	Description
1	4	integer	Vertex Index
2	4	integer	Bones Count
if BonesCount > 0 then there is an array, repeated for the Bones Count
1	4	integer	Bone name string length
2		string	Bone name string
3	4	float	Weight