JOE format - Revision history

Timo 6: Update categories

2012-09-01T10:33:21Z

Update categories

Timo 6: Formatting style updates

2012-08-27T13:51:18Z

Formatting style updates

Timo 6: 13 revisions: Import from old wiki (on 15 May 2012)

2012-08-26T17:24:42Z

13 revisions: Import from old wiki (on 15 May 2012)

New page

This format is based on the md2 format but with a few enhanced features. It can be written to using a python export script for the Blender 3D modeling package.

==Technical specification==

"JOE" is a binary file format in which multi-byte values are expressed with the little-endian byte order. This section details version 3 of the file format.

''Note: This documentation was generated by reverse engineering model.h and modle.cpp and inspecting the python blender export script. So there may be errors in evaluation.''
=== Data Type Map ===
The following table explicitly defines the various data types used in a JOE file.
{|
!Identifier!!Detailed Description
|-
|int||32-bit signed integer
|-
|short||16-bit signed integer
|-
|short3||Three consecutive shorts forming an array
|-
|float||32-bit floating-point value.
Unsure of the exact format... probably whatever is implemented by x86 machines.
|-
|float3||Three consecutive floats forming an array.
|}

=== File Header ===
This block of information initiates every file.

{| border="1" width="100%"
!data type!!block offset!!name!!description
|-
|int||0||magic
|'''8441211611'''(0x1F722AADB): number used to identify the file as a JOE file. Currently unchecked by vdrift.
|-
|int||4||version
|report the file version that this file conforms to. This specification details version 3 of the format.
|-
|int||8||num_faces
|every frame is expected to contain the same number of faces (polygons) this value specifies how many. This is currently limited to 32000.
|-
|int||12||num_frames
|Presumably, this details the number of frames used in an animation. Currently constrained to "1"
|}

=== Frame Format ===
details a single configuration of a model. "File Header.num_frames" frames follow the file header.

{| border="1" width="100%"
!data type!!block offset!!name!!description
|-
|int||0||num_verts
|the number of vertices used in this frame
|-
|int||4||num_textcoords
|the number of texture coordinates used in this frame.
|-
|int||8||num_normals
|the number of vertex normals used in this frame.
|}

after each frame header, you will find
* File Header.num_faces Face blocks
* num_verts Vertex blocks
* num_normals Vertex blocks
* num_textcoords Texture Coordinate blocks

=== Face Format ===
Each frame as "File Header.num_faces" face records immediately following the Frame header (decribed above). A face is basically several lists of indices in to vertex, normal, and text coord arrays described in following sections.

For this version, a face is always a triangle ( i.e. a three-vertex polygon ).

{| border="1" width="100%"
!data type!!block offset!!name!!description
|-
|short3||0||vertexIndex
|Indeces in to the vertex array. These two constructs together define the location of each corner of the face in 3d space.
|-
|short3||6||normalIndex
|Indeces in to the normals array. These two constructs help define how light sources interact with the face at each corner. Normals also help define which side of a face is "front".
|-
|short3||12||textureIndex
|Indeces in to the texture coordinate array. These two constructs together help define which portions of a texture image map to each corner of the face. Note that in the future there may be a multiple of 3 entries in this array to accomidate applying many textures to a single face. Which images are used as textures by a particular model are defined by convention and explained in [[Car files and formats]] and [[Track files and formats]]
|}

=== Vertex Format ===
A vertex block simply contains a three-element float array. Vertex blocks may have a misleading name because they are used for both vertices and normals.

{| border="1" width="100%"
!data type!!block offset!!name!!description
|-
|float3||0||vertex||A three-element float array defining the X, Y, and Z components of a vertex at offsets 0, 4, and 8 respectively
|}

=== Texture Coordinate Format ===
A texture coordinate is a 2-dimensional coordinate used to map prtions of a texture to a model vertex.
{| border="1" width="100%"
!data type!!block offset!!name!!description
|-
|float||0||u||a value between 0 and 1 indicating a position along the width of the texture
|-
|float||4||v||a value between 0 and 1 indicating a position along the height of the texture.
|}

[[Category:Files]]
[[Category:Review]]

Venzon: New page: This format is based on the md2 format but with a few enhanced features. It can be written to using a python export script for the Blender 3D modeling package.

2007-04-27T02:16:21Z

New page: This format is based on the md2 format but with a few enhanced features. It can be written to using a python export script for the Blender 3D modeling package.

New page

This format is based on the md2 format but with a few enhanced features. It can be written to using a python export script for the Blender 3D modeling package.

← Older revision		Revision as of 10:33, 1 September 2012
Line 102:		Line 102:

	[[Category:Files]]		[[Category:Files]]
−	~~[[Category:Review]]~~

@@ Line 2: / Line 2: @@
 ==Technical specification==
-"JOE" is a binary file format in which multi-byte values are expressed with the little-endian byte order. This section details version 3 of the file format.
+{{note|This documentation was generated by reverse engineering model.h and modle.cpp and inspecting the python blender export script.  So there may be errors in evaluation.}}
 === Data Type Map ===
 The following table explicitly defines the various data types used in a JOE file.
-{|
+{| border="1"
 !Identifier!!Detailed Description
 |-
@@ Line 26: / Line 26: @@
 This block of information initiates every file.
-{| border="1" width="100%"
+{| border="1"
 !data type!!block offset!!name!!description
 |-
@@ Line 45: / Line 45: @@
 details a single configuration of a model.  "File Header.num_frames" frames follow the file header.
-{| border="1" width="100%"
+{| border="1"
 !data type!!block offset!!name!!description
 |-
@@ Line 64: / Line 64: @@
 * num_textcoords Texture Coordinate blocks
-=== Face Format ===
+===Face Format===
 Each frame as "File Header.num_faces" face records immediately following  the Frame header (decribed above). A face is basically several lists of indices in to vertex, normal, and text coord arrays described in following sections.
 For this version, a face is always a triangle ( i.e. a three-vertex polygon ).
-{| border="1" width="100%"
+{| border="1"
 !data type!!block offset!!name!!description
 |-
@@ Line 82: / Line 82: @@
 |}
-=== Vertex Format ===
+===Vertex Format===
 A vertex block simply contains a three-element float array.  Vertex blocks may have a misleading name because they are used for both vertices and normals.
-{| border="1" width="100%"
+{| border="1"
 !data type!!block offset!!name!!description
 |-
@@ Line 91: / Line 91: @@
 |}
-=== Texture Coordinate Format ===
+===Texture Coordinate Format===
 A texture coordinate is a 2-dimensional coordinate used to map prtions of a texture to a model vertex.
-{| border="1" width="100%"
+{| border="1"
 !data type!!block offset!!name!!description
 |-