P3D File Format - ODOLV4x

Introduction

Acknowledgements

This body of work is due to Synide's sweat and tears. To whom, all honour and glory. Ably assisted by T_D and Mikero that further detailed the data and gave this article a more general and correct structure.

General

The general format of an ArmA ODOLV4x p3d model is similar to the ODOLV7 format. The major differences are that ArmA models have

• an optional model.cfg, and
• Lods occur in the file from highest to lowest LodType value.

Legend

see Generic FileFormat Data Types

Relative Coordinates

All coordinates are relative to ModelInfo.CentreOfGravity

File Paths

The PrefixRoot\ folder.

Life for modellers would be far less tedious if filenames could also be relative to the p3d they are encountered in. Altering or moving or renaming the pbo (and specifically it's prefix) would not alter the relative location of the paa's it contains.

BI choose to use hard-wired Pbo-Prefix-addressing ONLY.

All hardwired addressing is relative to a built-in-situ (ie virtual) PrefixRoot\ folder

Each and every pbo in Arma contains a unique identity name, a prefix. Irrespective of the name of the pbo, the prefixname is THE name of the pbo from the perspective of the engine. In most cases, the prefixname is, conveniently, the filename. One huge advantage of this mechanism, sorely sorely missed in OFP. is that self-documenting increasing revisions of an addonV123.pbo can be supplied to Arma, with no changes to the mission sqms and other pbos that refer to it.

The PrefixRoot\ folder contains the prefix names of all pbos encountered (almost) ANYWHERE.

Thus the pbos in the Official Addons folder, the Oem Mods\Addons folder(s), the Dta core and bin pbo's, are all examined for their unique prefix names. These prefix names become the dictionary index of where the pbo really is, AND, what filename it actually is.

Thus all filename references in a p3d, *unconditionally* contain a prefixname\someFile\SomeWhere.

In most cases they refer to the very same pbo as the containing p3d and a great pity that the extraneous information could not have been removed by (optional) relative addressing as it requires a great deal of fiddling about when modifying models.

Note also that there is some inconsistency in filename paths. Most do not have a leading \. Some, require it. Both are indeed \hardwired

An Example:

P3dProxyName ="\ca\a10\agm65";

The immediate (and unfortunate) impression is that there is an A10 folder inside the official CA.pbo addon. In fact, the prefix of the A10.pbo = "ca\A10". Thus this reference is to the A10.pbo within which, is a agm65.p3d in it's root folder. (and again, this reference is in fact an extraneous reference to itself since the referring p3d (A10.p3d) is in the same pbo)

Versions

This Document covers ODOL versions:

V40 (Arma1)

• Original Arma1 binarised p3d

VBS2

• ModelInfo now has a 24 byte thermal profile appended

V43 (Arma2a)

• As per VBS2 plus

• An extra byte at end of Skeleton structure: always 0

• LZSS compression is still used at this level

V47 (Arma2b LZO)

As per V43 plus:

• all compressed blocks are LZO compressed

• CompressedMinMax block is now nMinMax*8 in size

• CompressedNormals block is now nNormals*4 in size

• LodFrame has 4 extra floats

• UVSet structure changed to:

LodUV
{
 float  uvScaling[4];
 ulong  nVertices;
 tbool  DefaultFill;
 if (DefaultFill)
  float                        UV;              // default fill for all nVertices
 else
  float                        UV[nVertices];   // potentially compressed
}

V48 (Arma2c)

As per V47 plus:

• ModelInfo has a 4 byte appendix

Arma2c format is the mainstay of Arma2. Types 43 and 47 are rarely encountered being works-in-progress in the initial release.

V49 (Arrowhead)

As per V48. No known differences apart from version number

V50 (Arrowhead DLC)

Introduced in pmc and baf DLC

• additional count after usedbones

lodPointFlags swapped around

V52 (TOH)

intoduced in patch to BAF DLC, used mostly in TOH

• additional float after usedbones

---

File Format

ODOLv4x
{
 StandardP3DHeader Header;
 ModelInfo         ModelInfo; // see P3D Model Info
 Animations        Animations;
 ulong             StartAdressOfLods[Header.NoOfLods];// offset relative to start of file.
 ulong             EndAdressOfLods  [Header.NoOfLods];
 LODFaceDefaults   LODFaceDefaults;
 ODOLv40Lod        ODOLv40Lods[Header.NoOfLods];  
 }//EndOfFile

Structures

StandardP3DHeader

struct
{
  char[4]  Filetype; // "ODOL"
  ulong    Version;  // 40
  ulong    NoOfLods; // alias NoOfResolutions;
}

common header structure for all P3D file formats

Animations

Animations
{
 tbool             AnimsExist;
 if (AnimsExist)
 {
  ulong            nAnimationClasses; // eg NoOfAnimSelections;
  AnimationClass   AnimationClasses[nAnimationClasses];

  long             NoOfResolutions;// is -1 if nAnimationClasses == 0
  Bones2Anims      Bones2Anims[NoOfResolutions];
  Anims2Bones      Anims2Bones[NoOfResolutions];
  //For every bone there is a list of Animations for each resolution
  //And, a reversed table of every Animation gets a Bone.
  //The reversed table optionally appends axis info dependent on the AnimTransformType
 }
}

AnimationClass

AnimationClass { ulong AnimTransformType; asciiz AnimClassName; // "RightDoor" asciiz AnimSource; // "rotor" float MinMaxValue[2]; float MinMaxPhase[2]; ulong sourceAddress; switch(AnimTransformType) case 0://rotaton case 1://rotationX case 2://rotationY case 3://rotationZ float angle[2]; break; case 4://translation case 5://translationX case 6://translationY case 7://translationZ float offset[2]; break; case 8: //"direct" float axisPos[3]; float axisDir[3]; float angle; //in radians whereas the model.cfg entry is in degrees float axisOffset; break; case 9: //"hide" float hideValue; break; }

corresponds to model.cfg
class CfgModels
{
 ....

 class whateverModel: Default
 {
  ...
  class Animations
  {
   class RightDoor //AnimClassName
   {
     type = "translation";//AnimTransformType
     source = "rotor";    //AnimSource
     etc

Bones2Anims

Bones2Anims
{
 ulong        NoOfBones;
 Bone2AnimClassList   Bone2AnimClassLists[NoOfBones];
}

Bone2AnimClassList

Bone2AnimClassList
{
 ulong NoOfAnimClasses;
 ulong AnimationClassIndex[NoOfAnimClasses]; // a (sometimes repeating) list of zero based indexes into above animation classes
}

Anims2Bones

Anims2Bones
{
 AnimBones AnimBones[Animations.nAnimationClasses];
}

AnimBones

every lod contains an identical list of animation entries that declare the position and axis of the each animation classes

AnimBones
{
 long SkeletonBoneNameIndex; // zero based index to the SkeletonBoneName name & parentname
 // equivalent to selection = "LeftDoor"; eg in the model.cfg
 /*
 ** SkeletonBoneNameIndex== -1 when no skeleton bone is for this Anim and (obviously?) no axis information follows.
 */
 if (SkeletonBoneNameIndex!= -1) && (AnimationClass.AnimTransformType != 8 || 9)
 {
 /*
 ** AnimationClass.AnimTransformType 8 (direct) and 9 (hide) never require axis information. 
 ** This because the "direct" (type 8) already has axis info in it's AnimationClass structure, 
 ** and "hidden" (type 9) clearly doesn't need it.
 */
    XYZTriplet axisPos; //describes the position of the axis used for this anim
    XYZTriplet axisDir;
 }
}

LODFaceDefaults

 tbool             UseDefault[Header.NoOfLods];
 FaceData
 {
  ulong   HeaderFaceCount;
  ulong   aDefaultLong;     //ffffffff or 6f 7a 80 fa eg
  byte    UnknownByte;      //generally zero
  byte    aFlag;            // zero or one
  bytes   Zeroes[7];
  ======if v52 =========
  ulong   AnotherCount;
  float   AnotherFloat;
  =======endif===========
 }[Number of false UseDefault's];

A face data struct only exists for those lods who's UseDefault is zero

ODOLv4xLod

• Lod layout corresponds to Arma1 (type40). The differences in a2 are in the nitty gritty of the structures themselves. Arrowhead(v50) has some changes.
• TrueArma2 == type 47 or greater (lzo compression)
• Type 43 was a preliminary p3d prior to lzo compression. rarely encountered

 ODOLv4xLod
 {
   ulong                         nProxies;
   LodProxy                      LodProxies[nProxies];              // see P3D Lod Proxies
   ulong                         nLodItems;
   ulong                         LodItems[nLodItems];               // potentially compressed
   ulong                         nBoneLinks;
   LodBoneLink                   LodBoneLinks[nBoneLinks];
 =========if v5x==========
   ulong                         LodPointCount;
     if v52
   float                         UnknownV52Float;
    endif
   else
   LodPointFlags                 LodPointFlags;                     // Potentially compressed
===========endif==========
   float                         UnknownFloat1;
   float                         UnknownFloat2;
   XYZTriplet                    MinPos;
   XYZTriplet                    MaxPos;
   XYZTriplet                    AutoCenterPos;
   float                         Sphere;                            // same as geo or mem values in modelinfo, if this lod is geo or memlod of course
   ulong                         NoOfTextures;
   asciiz                        LodPaaTextureNames[NoOfTextures];  //"ca\characters\hhl\hhl_01_co.paa"
   ulong                         NoOfMaterials;
   LodMaterial                   LodMaterials[NoOfMaterials];
   LodEdges                      LodEdges;                          // compressed see P3D Lod Edges
   ulong                         NoOfFaces;
   ulong                         OffsetToSectionsStruct;            // see below
   ushort                        AlwaysZero;
   LodFace                       LodFace[NoOfFaces];                // see P3D Lod Faces
   ulong                         nSections;
   LodSection                    LodSections[nSections];            // see P3D Lod Sections
   ulong                         nNamedSelections;
   LodNamedSelection             LodNamedSelections[nNamedSelections]; //See P3D Named Selections potentially compressed
   ulong                         nTokens;
   NamedProperty                 NamedProperties[nTokens];
   ulong                         nFrames;
   LodFrame                      LodFrames[nFrames];  //see P3D Lod Frames
   ulong                         IconColor;
   ulong                         SelectedColor;
   ulong                         UnknownResidue
   byte                          UnknownArmaByte;
   ulong                         sizeOfVertexTable; //(including these 4 bytes)
   if (v5x)
   LodPointFlags                 LodPointFlags;                     // Potentially compressed
   endif
   VertexTable                   VertexTable;
 }

VertexTable

all arrays are subject to compression

struct
{
   UvSet                         DefaultUVset;
   ulong                         nUVs;                       //in error, V47 sometimes sets nUV's as 0 but means 1
   UvSet                         UVSets[nUVs-1];
   ulong                         NoOfPoints;
   XYZTriplet                    LodPoints[NoOfPoints];
   ulong                         nNormals;
   (A2)LodNormals                LodNormals[nNormals]; 
   ulong                         nMinMax;
   (A2)LodMinMax                 MinMax[nMinMax];            //optional
   ulong                         nProperties;
   VertProperty                  VertProperties[nProperties];//optional related to skeleton
   ulong                         Count;
   UnknownVtxStruct              UnknownVtxStructs[Count];   //optional
  }

• All non zero counts counts are the same.
• Points,PointFlags, Normals and UV1 arrays are an integral group, they are either all there, or not specified (RacetK.p3d, a FrameTime lod has no counts at all)
• UV2,MinMax, VertProperties and Unknown are optional in the sense that their counts can individually be zero, else they are the same as the others
• In Odol7 PointFlags are part of this stucture, in Arma, they are a separated table.

CompressedFill Arrays

LodPointFlags, LodUV's and LodNormals arrays are not only subject to the standard 1024 rule compression, but also have a fill byte.

struct
{
 ulong                         Count;
 tbool                         DefaultFill;
 if (DefaultFill)
  type                         Array;          // default fill for all Counts
 else
  type                         Array[Count];   // potentially compressed
}

The structure either contains a single set of type variables, or, an array of type variables. If a full array is declared (DefaultFill =false) then that array is subject to the 1024 rule as per normal.

UVset

if TrueARMA2
   float                         UVScale[4];
endif
   (A2)LodUV                     LodUV; 

LodUV

CompressedFill type = UVPair // eg float U,V;

A2LodUV

CompressedFill type = float // eg float UV;

LodNormals

 CompressedFill type = XYZTriplet

A2LodNormals

 CompressedFill type = CompressedXYZTriplet

CompressedXYZTriplet

contains 3 x 10 bit fields in a 32bit 'integer'

code for converting back to a standard XYZTriplet is:

void DecodeXYZ(ulong CompressedXYZ, XYZTriplet *triplet)
{
   double scaleFactor = -1.0 /511;
   trp->X=trp->Y=trp->Z=0.0;
   int x=   CompressedXYZ       & 0x3FF;
   int y = (CompressedXYZ>> 10) & 0x3FF;
   int z = (CompressedXYZ>> 20) & 0x3FF;
   if (x > 511) x -= 1024;
   if (y > 511) y -= 1024;
   if (z > 511) z -= 1024;
   if (x) trp->X = (float)(x * scaleFactor);
   if (y) trp->Y = (float)(y * scaleFactor);
   if (x) trp->Z = (float)(z * scaleFactor);
}

LodPointFlags

CompressedFill type = ulong bits

This table is the equivalent of Oxygen's points->properties dialog box. It specifically stores the user values and other flags for that point.

In ODOl7 it was part of the vertex table. In Arma, it is separate.

See P3D Point and Face Flags

LodMinMax

CompressedArray
{
 XYZTriplet     MinMax[Count][2]; // 2 == min vs max
}

A2LodMinMax

CompressedArray
{
 float         MinMax[Count][2]; // 2 == min vs max
}

VertProperty

CompressedArray
{
 ulong  index;// seen range 0..4
 ulong  V,V; // definate not floats. might be flags, or indices
}

UnknownVtxStruct

CompressedArray
{
 ulong  Unknown[2][2]; // seems to be arranges as flag,0, 0, 0,
}

LodBoneLink

LodBoneLink
{
  ulong NoOfLinks;         //range 0..3
  ulong Value[NoOfLinks];  //the 'Value' seems to reference the 'LodItems' structure, resulting in a circular-reference.
}

LodMaterial

Basically... A direct replication of the information in the given .rvmat file

The stages in the p3d include a default stage and a TI stage that are not normally listed in the rvmat.

The first stage (in the p3d) is unconditionally the default stage. It is defaulted to empty (RvMatName=""), unless, specified in the rvmat

The last stage is the TI stage, and is also defaulted empty, unless specified in the rvmat.

TI Stages were introduced for operation arrowhead. Lod Material Types 9 and 10 (Arma1 and Arma2) do not have a TI stage at all.

Neither of these two special, hidden, stage types use uvsets. The transform matrix for them is defaulted empty (so-called 'TexGen0').

When specified in the rvmat (class Stage0 and StageTI respectively), no class uvTransform is declared for them. It is assumed default empty.

In an rvmat, uvTransforms are ordinarily declared within each stage body.

In a P3D, identical UVTransforms are declared once, and multiple 'stages' refer to them. There is, always, a default UVSet0 Transform as the 1st entry. (IE some stages dont require uvsets)

This P3D style can, if preferred, be used in rvmat syntax as

class TexGenX
{
  .......
};

class StageZ
{
  .........
  Texgen=X;
};

where X and Z are numbers

 LodMaterial
 {
   asciiz            RvMatName;     // "ca\characters\data\soldier_captive_hhl.rvmat"
   ulong             Type;          // 9 == Arma, 10==VBS2,11==Arrowhead
   D3DCOLORVALUE     Emissive;
   D3DCOLORVALUE     Ambient;
   D3DCOLORVALUE     Diffuse;
   D3DCOLORVALUE     forcedDiffuse;
   D3DCOLORVALUE     Specular;
   D3DCOLORVALUE     Specular2;       //Usually same as Specular
   float             SpecularPower;
   ulong             PixelShaderId;   //See enumPixelShaderId
   ulong             VertexShaderId;  //See enumVertexShaderId
   LongBool          Arma1UnKnownBool;//A2 deprecated, always 1
                                      //A1 mostly 1 otherwise 0
   ulong             Arma1AnIndex;    //A2 deprecated, always 1
                                      //A1 0,1 or 2
   asciiz            BiSurfaceName;   // "ca\data\Penetration\plastic.bisurf"
   LongBool          Arma1Mostly0x01; //A2 deprecated, always 1
                                      //A1 rarely zero
   ulong             RenderFlags;     //Generally 0
   ulong             nTextures;
   ulong             nTransforms;     // always same as nTextures
   LodStageTexture   StageTextures  [nTextures];
   LodStageTransform StageTransforms[nTransforms]; 
   if type>=10//vbs2/arma2
    LodStageTexture   DummyStageTexture;
    if type==11//arrowhead
     byte             Always0;
    endif
   endif   
 }  

Each lodmaterial entry contains a default StageTexture and StageTransform as the first entry. It is not shown in the rvmat file and has no PaaTexture

It is the only entry if a SurfaceName exists.

D3DCOLORVALUE

D3DCOLORVALUE
{
  float r,g,b,a;
}

RenderFlags

• Bit0:AlwaysInShadow (A1 only)
• Bit1:NoZWrite
• Bit4:NoColorWrite
• Bit5:NoAlphaWrite
• Bit6:AddBlend
• Bit7:AlphaTest (clutter)
• Bit8:AlphaTest64 (clutter)
• Bit19:Road (a1only)
• Bit11:NoTiWrite

LodStageTexture

LodStageTexture
{
 ulong  TextureFilter; // see below
 asciiz PaaTexture;    // "ca\characters\data\civil_tvreport_body_as.paa
                       // alternatively "#(argb,8,8,3)color(0,0,0,1,CO)" (eg)
 ulong  TransformIndex;       // zero based, see below
};

The first stageTexture is a dummy entry. For N humanly readable stage classes, there are 1+N LodStageTextures

Later p3d formats (VBS2, Operation Arrowhead) append an additional classTI LodStageTexture. if not present or declared in the rvmat file, it is a dummy entry. The rvmat gui editor from BisTools is not able to display this.

The TransformIndex is generally iterative (linear sequential). 1st entry is 0, 2nd 1, 3rd 2, etc. It refers to the nTH Transform Matrix

TextureFilter maybe 1 of the following values.

• 0: Point // sometimes
• 1: Linear // rarely
• 2: TriLinear // not seen
• 3: Anisotropic (default)

LodStageTransform

  LodStageTransform
  {
   ulong UVSource;
   float Transform[4][3];//a DirectX texture space transform matrix
  };

UVSource corresponds to the 8 possible uvsets available

• 0 "None"
• 1 "Tex" default
• 2: "Tex2"
• ........
• 8:"Tex8"

• Tex1..8 cannot be taken literally as uvsource 1..8. They can mean anything, according to the template and are scarcely encountered

NamedProperty

 struct
 {
    Asciiz Property;// "noshadow" = "1" eg
    Asciiz Value;
 }

Decompression

see Compressed LZSS File Format

see Compressed LZO File Format

In ODOL v40 and v43 format files, some of the data structures present in the file are compressed by using LZSS compression. ODOL v47 and v48 use LZO compression.

Unlike pbo compression, in ArmA model files, one only knows the number of items to decompress, the expected output size (in bytes) and the expected checksum. With this information and the size of a given data item one has the necessary information to expand the data to it's original format and size.

Note:- Data structures that are identified as being compressible will only be compressed if the 'expectedSize' is >= 1024 bytes.

As an example if one was expanding the array of vertices positions...

• A vertex is described by it's x,y,z coordinates which are floats. A float is a 32bit (4 byte) number.
• If we were processing 1968 vertices then our expected output size would be 1968 * (3 * 4) = 23,616 bytes.

This 'expectedSize' is the only necessary information one would need to pass to a processing sub-routine or function.

Reference Tables

Material Stages

The number of material stages is dependant on the type of Shader that is used to process the material by the ArmA game engine. A reference table is used when processing materials where depending on the shader specified the given number of stages should be processed.

refShaderStages { int PixelShaderId; int NoOfStages; };

ID (Hex/Decimal)	Name	Description	NoOfStages
0x00, 0	Normal	diffuse color modulate, alpha replicate	0
0x01, 1	NormalDXTA	diffuse color modulate, alpha replicate, DXT alpha correction	0
0x02, 2	NormalMap	normal map shader	3
0x03, 3	NormalMapThrough	normal map shader - through lighting	3
0x04, 4	NormalMapSpecularDIMap	VBS2 only	2
0x05, 5	NormalMapDiffuse	?	2
0x06, 6	Detail	?	1
0x07, 7	?	?	?
0x08, 8	Water	A1 only sea water	2
0x09, 9	?	vbs2	?
0x0A, 10	White	A1 only	0
0x0B, 11	?	vbs2	?
0x0C, 12	AlphaShadow	shadow alpha write	0
0x0D, 13	AlphaNoShadow	shadow alpha (no shadow) write	0
0x0E, 14	?	vbs2	?
0x0F, 15	DetailMacroAS	?	3
0x10, 16	?	vbs2	?
0x11, 17	?	vbs2	?
0x12, 18	NormalMapSpecularMap	?	2
0x13, 19	NormalMapDetailSpecularMap	Similar to NormalMapDiffuse	3
0x14, 20	NormalMapMacroASSpecularMap	?	4
0x15, 21	NormalMapDetailMacroASSpecularMap	?	5
0x16, 22	NormalMapSpecularDIMap	Same as NormalMapSpecularMap, but uses _SMDI texture	2
0x17, 23	NormalMapDetailSpecularDIMap	?	3
0x18, 24	NormalMapMacroASSpecularDIMap	?	4
0x19, 25	NormalMapDetailMacroASSpecularDIMap	?	5
0x38, 56	Glass	?	2
0x3A, 58	NormalMapSpecularThrough	?	3
0x3B, 59	Grass	Special shader to allow volumetric shadows to be cast on grass clutter	0
0x3C, 60	NormalMapThroughSimple	?	0
0xxx, 102	Super	Arrowhead	0
0xxx, 103	Multi	Arrowhead	0
0xxx, 107	Tree	Arrowhead	0
0xxx, 110	Skin	Arrowhead	0
0xxx, 111	CalmWater	Arrowhead	0
0xxx, 114	TreeAdv	Arrowhead	0
0xxx, 116	TreeAdvTrunk	Arrowhead	0

---

Enums

int enum VertexShaderId { case 0: return "Basic"; case 1: return "NormalMap"; case 2: return "NormalMapDiffuse"; case 3: return "Grass"; case 8: return "Water"; case 11: return "NormalMapThrough"; case 15: return "NormalMapAS"; case 14: return "BasicAS"; case 17: return "Glass"; case 18: return "NormalMapSpecularThrough"; case 19: return "NormalMapThroughNoFade"; case 20: return "NormalMapSpecularThroughNoFade"; case 23: return "Super"; case 24: return "Multi"; case 25: return "Tree"; case 30: return "CalmWater"; case 26: return "TreeNoFade"; case 29: return "Skin"; case 31: return "TreeAdv"; case 32: return "TreeAdvTrunk"; }

---

Links

Article Author - Sy (Synide) -- Sy 17:16, 11 August 2007 (CEST)

Original ODOLv40 Article detailed by Bxbx (Biki'd by Mikero)