Texture Native Struct
| {{{NAME}}} | |
|---|---|
| RenderWare Stream Section | |
| Vendor | {{{VENDORNAME}}} |
| Module | {{{MODULENAME}}} |
| Module ID | 0x{{{MODULEID}}}
|
| Identifier | 0x{{{IDENTIFIER}}}
|
| Chunk ID | 0x{{{MODULEID}}}{{{IDENTIFIER}}}
|
| Versions | All |
| Hierarchy | |
| Parents: None | |
| Children: None | |
| Extensions: None | |
| File Format | |
This article is about the Struct section accompanied by a Texture Native parent section.
The Texture Native Struct section can usually be found in texture archives used by the PC, XBOX and PS2 versions of the GTA III game trilogy. They are the most important sections inside a .txd file since they contain the names, dimensions and the actual image data for textures. The typical location in the file's section hierarchy is Texture Dictionary > Texture Native > Struct.
Images Header
There is a 86 byte header with general image information:
struct NativeTexturePC_Header
{
struct {
unsigned int platformId;
unsigned int filterMode : 8;
unsigned int uAddressing : 4;
unsigned int vAddressing : 4;
char name[32];
char maskName[32];
} TextureFormat;
struct {
unsigned int rasterFormat;
union {
D3DFORMAT d3dFormat; // SA
unsigned int hasAlpha // GTA3 & VC
};
unsigned short width;
unsigned short height;
unsigned char depth;
unsigned char numLevels;
unsigned char rasterType;
union {
unsigned char compression; // GTA3 & VC
struct { // SA
unsigned char alpha : 1;
unsigned char cubeTexture : 1;
unsigned char autoMipMaps : 1;
unsigned char compressed : 1;
};
};
} RasterFormat;
};struct NativeTexturePS2_Header
{
struct {
unsigned int platformId;
unsigned int filterMode : 8;
unsigned int uAddressing : 4;
unsigned int vAddressing : 4;
} TextureFormat;
// CHUNK_STRING for name
// CHUNK_STRING for alpha-mask name
//size: 64 bytes
struct RasterFormat
{
unsigned int width, height;
unsigned int depth;
unsigned int rasterFormat;
// See http://mtz01-a.stanford.edu/resources/SonyPS2/pdf00005.pdf
unsigned long long tex0; // PS2 TEX0 GS register
unsigned long long tex1; // PS2 TEX1 GS register
unsigned long long miptbp1; // PS2 MIPTBP1 GS register
unsigned long long miptbp2; // PS2 MIPTBP2 GS register
unsigned int texelDataSectionSize;
unsigned int paletteDataSectionSize;
unsigned int gpuDataAlignedSize; // size of mipmap texels + palette texels aligned to 2048
unsigned int skyMipmapVal; // always 4032
};
};- Platform ID
- This is 8 for GTA3 and VC on the PC, 9 for GTA SA on the PC, PS2\0 FourCC for GTA SA on PS2, and 5 for GTA3/VC/SA on the XBOX.
- Filter Mode
FILTER_NONE 0x00 FILTER_NEAREST 0x01 FILTER_LINEAR 0x02 FILTER_MIP_NEAREST 0x03 FILTER_MIP_LINEAR 0x04 FILTER_LINEAR_MIP_NEAREST 0x05 FILTER_LINEAR_MIP_LINEAR 0x06
- Addressing Mode
WRAP_NONE 0x00 WRAP_WRAP 0x01 WRAP_MIRROR 0x02 WRAP_CLAMP 0x03
- Raster Format
FORMAT_DEFAULT 0x0000 FORMAT_1555 0x0100 (1 bit alpha, RGB 5 bits each; also used for DXT1 with alpha) FORMAT_565 0x0200 (5 bits red, 6 bits green, 5 bits blue; also used for DXT1 without alpha) FORMAT_4444 0x0300 (RGBA 4 bits each; also used for DXT3) FORMAT_LUM8 0x0400 (gray scale) FORMAT_8888 0x0500 (RGBA 8 bits each) FORMAT_888 0x0600 (RGB 8 bits each, D3DFMT_X8R8G8B8) FORMAT_555 0x0A00 (RGB 5 bits each - rare, use 565 instead, D3DFMT_X1R5G5B5) FORMAT_EXT_AUTO_MIPMAP 0x1000 (RW generates mipmaps) FORMAT_EXT_PAL8 0x2000 (2^8 = 256 palette colors) FORMAT_EXT_PAL4 0x4000 (2^4 = 16 palette colors) FORMAT_EXT_MIPMAP 0x8000 (mipmaps included)
- Depth
- 4, 8, 16 or 32; 8 usually comes with palette
- Compression
- for more information, refer to S3 Texture Compression.
Raster Data
The header is followed by an optional palette and the raster data (pixels), according to the Raster Format flags.
If Raster Format is FORMAT_EXT_PAL8 | FORMAT_8888 or FORMAT_EXT_PAL8 | FORMAT_888, then a color palette of (up to) 256 RGBA colors is included. This is used in GTA3 quite often. The raster's one byte for each pixel is an index into the palette.
1024 byte - BYTE[256][4] - palette of RGBA colors 4 byte - DWORD - raster size w*h*1 byte - BYTE[w*h] - pixels, 1 byte each
If no palette is included, the header is followed by raster size and data. If mipmaps are included (FORMAT_EXT_MIPMAP) then this is repeated for each mipmap. With increasing mipmap levels the raster size is decreased by the factor 4 (side lengths halved). Small initial textures can result in mipmaps of the size 0. For uncompressed images:
4 byte - DWORD - raster size w*h*bpp/8 byte - BYTE[w*h][bpp/8] - pixels
Note: FORMAT_888(8) rasters use BGRA colors!
If DXT compression is used, blocks of 4x4 pixels occupy only 8 or 16 bytes (depending on the type).
PlayStation 2
The image and palette data is both handled in a (generic) texture format. There are special raster flags reserved.
#define RASTER_SWIZZLED 0x10000 // the images are "swizzled"
#define RASTER_HAS_TEXEL_HEADERS 0x20000 // the image data is preceeded by headersIf the rasterFlags contain the RASTER_HAS_TEXEL_HEADERS flag, then each image data and palette data have the following structure before it.
struct TextureDataHeader
{
unsigned int consts1[4]; // same in every TXD
unsigned long long trxpos; // PS2 GS transmission rectangle settings (only dsax and dsay are important)
unsigned int consts2[2]; // same in every TXD
unsigned int width, height; // texture dimensions
unsigned int consts3[6]; // same in every TXD
unsigned int texelCount; // number of texels divided by 4
unsigned int consts4[3]; // same in every TXD
};The actual image data is stored afterward. It is packed in either PSMCT32, PSMCT16, PSMT8 or PSMT4 internal GS types according to the documentation. So before you can get usable images in linear format out of PS2 textures, you have to "unswizzle" them. This is done by permuting the data.
