RwBinaryStream

From GTAMods Wiki
Revision as of 21:30, 29 May 2007 by Shrew (talk | contribs)
Jump to navigation Jump to search

Reading Binary Streams

RwStreams are heirarchical streams of sections. Every section consists of:

  • (gauranteed) RwHeader
  • (gauranteed) RwData child section (the contents are specific to the section type, see definitions below.)
  • (optional) Children sections

The RwHeader contains the size (sectionSize member) of all the data and children (and their data and children). This allows you to either skip the entire section and it's children by advancing the stream pointer, or to know when you have parsed all it's children by comparing the stream pointer to the address of the section RwHeader added to the sectionSize.


Simple Pseudo C++ Code to read a Binary Stream

//-----------------------------------------------------------------------
// The RwSection is a base class from which all RwType classes derive

RwSection * ReadSection(FileStream * stream, RwSection * parent)
{
	//-----------------------------------------------------------------------
	// read the header
	
	RwHeader header = ReadRwHeader(stream);
	
	//-----------------------------------------------------------------------
	// create the section - the type returned is based on header.sectionType
	// the reason the parent is passed in is because if the section is an
	// rwDATA what data it reads is dependant on the parent's sectionType and
	// also the number of rwDATA children the parent already has read
	
	RwSection * section = CreateAppropriateSection(stream, header.sectionType, parent);
	
	//-----------------------------------------------------------------------
	// recursively read the children
	
	u8 * endOfSection = stream.GetPosition() + header.sectionSize;
	while(stream.GetPosition() < endOfSection)
	{
		RwSection * childSection = ReadSection(stream, section)
		section->AddChild(childSection);
	}
	
	//-----------------------------------------------------------------------
	// return the newly created section
	
	return section;
}


RwType

enum
{
    rwDATA = 1,
    rwSTRING = 2,
    rwEXTENSION = 3,
    rwTEXTURE = 6,
    rwMATERIAL = 7,
    rwMATERIALLIST = 8,
    rwFRAMELIST = 14,
    rwGEOMETRY = 15,
    rwCLUMP = 16,
    rwLIGHT = 18,
    rwATOMIC = 20,
    rwTEXTURENATIVE = 21,
    rwTEXDICT = 22,
    rwGEOMETRYLIST = 26,
    rwMATERIALSPLIT = 124,
    rwFRAME = 39056126,
    rwPLUGIN_PARTICLES = 0x118,
    rwPLUGIN_MATERIALEFFECTS = 0x120,
    rwPLUGIN_BINMESH = 0x50e,
};


RwHeader

struct RwHeader
{
    s32 sectionType; // RwType
    s32 sectionSize;
    u8 unknown[2];
    s16 versionNumber;
};


RwClump

Possible Children

  • RwFrameList
  • RwGeometryList
  • RwAtomic


RwData (1st, gauranteed)

Data type Name Version number Condition Notes
u32 objectCount all
u8[8] unknown 3074, 4099, 6147


RwData (2nd and subsequent, optional)

Data type Name Version number Condition Notes
u8[4] unknown 3074, 4099, 6147


RwGeometryList

Possible Children

  • RwGeometry


RwData (1st, gauranteed)

Data type Name Version number Condition Notes
u32 geometryCount all

RwGeometry

Possible Children

  • RwMaterialList
  • In RwExtension
    • RwBinMeshPlugin
    • RwMorphPlugin


RwData (1st, gauranteed)

Data type Name Version number Condition Notes
u16 flags all
u8[2] unknown all
u32 triangleCount all
u32 vertexCount all
u32 morphTargetCount all
u32 ambientRgba 0, 2048, 3074
u32 diffuseRgba 0, 2048, 3074
u32 specularRgba 0, 2048, 3074
u32[vertexCount] vertexRgba all only if( flags & flags.COLOUR)
f32[vertexCount][2] uvs all only if( flags & flags.TEXTURE) For versions 0, 2048 and 3074 the u and v are swapped
u16[triangleCount][3] faces all For every face, read 4 u16s. and ignore the 3rd
vector3 boundingSpherePosition all
f32 boundingSphereRadius all
u8[8] unknown all
vector3[vertexCount] positions all
vector3[vertexCount] normals all only if( flags & flags.NORMALS)


RwMaterialList

Possible Children

  • RwMaterial


RwData (1st, gauranteed)

Data type Name Version number Condition Notes
u32 materialCount all
u8[materialCount*4] unknown all


RwMaterial

Possible Children

  • RwTexture


RwData (1st, gauranteed)

Data type Name Version number Condition Notes
u8[4] unknown all
u32 colorRgba all
u8[4] unknown2 all
u32 textureCount all
u8[12] unknown3 all


RwTexture

Possible Children

  • RwTexture


RwData (1st, gauranteed)

Data type Name Version number Condition Notes
u8[4] unknown all
u32 colorRgba all
u8[4] unknown2 all
u32 textureCount all
u8[12] unknown3 all