P3D File Format - ODOLV40 Obsolete

The following information has been provided by BxBx and included by Mikero

Legend

//Legend 
//byte = 1 char = 8 bits 
//int = 4 byte = 32 bits; signed integer
//ulong = unsigned long, 4 bytes 
//ushort = unsigned short 2 bytes 
//asciiz = variable length zero terminated string. 
//float = 4 bytes (single precision)
//bool8 = 1 byte = 8 bits; boolean; 0 or 1

basics

Blocks in Odol V40 are quite similar to Odol v7 but placed in reverse order. 

Resolution table, 
LOD tables last to first
 
The same LZ compression is used for LODs as ODOL v7

known data: 

Beginning of file (Header signature)

HeaderTop

struct OdolV40
{
char signature[4]  //ODOL
long Version        //0x28, 40 dec
long lod_count

other

float resolutions[lod_count]
{
 long  u1;
 float u2,u3,u4
} // unknown data, same data follows on end of ODOL v7

byte   u5[139];      // unknown data , still same length as v7
Asciiz skeleton_name // Note: A Skeleton may not exist 
if (*skeleton_name)
{
 bool    u6 // 8bit boolean // value 1 or 0
 int     bone_count
 struct  bones[bone_count]
 {
   Asciiz bone1,bone2;
 }  
}

char u7[0x26]     // unknown data
Asciiz modelclass, modelparent // I think purpose this data found values 'houseno' 
                               //housebuilding',....  
char u8[5]        // unknown data
bool8 exist_anims
if (exist_anims)
{
 int anims_count
 struct anims[anims_count]
 {
   int  type        // 0,4,9 // rotation,move,.., i dont check it yet
    Asciiz name,parent
   float tr[6]  // transformations values
   if (type!=9) int u9
 }
}

unknowdata[unknowlength] // handle seek

struct lod[lod_count]
{
 int     vertices count 
 bool8   ub1
 if (ub1) char uch[11]  // unknow data
 char    uch[0x29]   // unknow data
 int     textures_count
 Asciiz  texture[textures_count]
 int     materials_count
 struct  materials[materials_count]
 {
  Asciiz  name
  char    uch[0x85] // unknowdata // some float values
  int     textures_count
  struct  textures_in_material[textres_count]
  {
   int    u10 // value 3 still
   Asciiz t_name
   int    u11 // self increment value // 0,1,2,3,4,...
  }
  char uch[0x34*textres_count] // some struct with same length 
       //as textures_in_material 
       // I dont work with material now, I skip it.
 }
 if ( textures_count>0 ) char uch[7];
 bool8 ub // unknown value
 int faces_count
 char u12[6]
 struct faces[6]
 {
  char dot_count
  unsigned short dot_vertice_index[dot_count]
 }
 unknowdata[ubknowlength]
 int components_count
 struct components[components_count]
 {
  char *name;
  int selected_faces_count
  ushort selected_faces[selected_faces_count] // if selected_faces_count > 0x100 
          // then compresed by LZ
  int    u14;
  ushort u15[u14]
  bool8 ub
  if (ub) int u16
  char uch[3]
  bool8 ub2
  int selected_vertices_count
  ushort selected_vertices[selected_vertices_count] // if selected_vertices_count > 0x100
//  then compresed by LZ
  int   u17
  char  uch[u17];
 }
 int named_properties_count
 struct named_properties[named_properties_count]
 {
  char * name,*value
 }

 unknowdata[mostly 0x15 , but not every time]

 int vertices_count // again same value
 bool8 ub
 if (ub)
 {
   struct UV[vertices_count] {float u,v} if count > 127 then LZ
 }
 else char uch[8]
 int u[18]
 int vertices_count
 struct vertices_pos[verices_count]{float x,y,z}

normals and the other data follow ,but this is in progress
}

I cannot find face.texture_index informations, in M16A4 are only 2 textures and I texture it handly by original UVsets.

links

1st ARMA MLOD M16A4 on BIForum
OFP ODOLv7 
More about LZ compresion ODOLv7