This function load a *.tga texture file and convert to OpenGL pixel format, uncompress only.
#pragma pack(1) struct TgaHeader
{
unsigned char m_IDLength;
unsigned char m_ColorMapType;
unsigned char m_ImageType;
unsigned short m_CMapStart;
unsigned short m_CMapLength;
unsigned char m_CMapDepth;
unsigned short m_XOffset;
unsigned short m_YOffset;
unsigned short m_Width;
unsigned short m_Height;
unsigned char m_PixelDepth;
unsigned char m_ImageDescriptor;
}; #pragma pack()
bool LoadTGA(const char *pszFileName, unsigned char *pBuffer, int iBufferSize, int *pInternalFormat, int *pWidth, int *pHeight)
{
FileHandle_t pFile = g_pFileSystem->Open(pszFileName, "rb"); if (!pFile)
return false; TgaHeader Header;
memset(&Header, , sizeof(Header)); g_pFileSystem->Read(&Header, sizeof(Header), pFile); if (Header.m_ImageType != )
{
g_pFileSystem->Close(pFile);
return false;
} if (Header.m_PixelDepth != && Header.m_PixelDepth != )
{
g_pFileSystem->Close(pFile);
return false;
} uint32 iPixelSize, iImageSize; switch (Header.m_PixelDepth)
{
case :
iPixelSize = ;
*pInternalFormat = GL_RGB;
break;
case :
iPixelSize = ;
*pInternalFormat = GL_RGBA;
break;
} iImageSize = Header.m_Width * Header.m_Height * iPixelSize; if (iImageSize > (uint32)iBufferSize)
{
g_pFileSystem->Close(pFile);
return false;
} uint32 iLineSize = Header.m_Width * iPixelSize;
uint32 iLinePos; for (uint32 y = ; y < Header.m_Height; ++y)
{
iLinePos = (Header.m_Height - y - ) * iLineSize;
g_pFileSystem->Read(&pBuffer[iLinePos], iLineSize, pFile);
} for (uint32 i = ; i < iImageSize; i += iPixelSize)
{
pBuffer[i + ] ^= pBuffer[i + ];
pBuffer[i + ] ^= pBuffer[i + ];
pBuffer[i + ] ^= pBuffer[i + ];
} *pWidth = Header.m_Width;
*pHeight = Header.m_Height; g_pFileSystem->Close(pFile);
return true;
}