//-----------------------------------------------------------------------------
// Does a texture have alpha?
//-----------------------------------------------------------------------------
static bool DoesTextureUseNormal( const char *pTextureName, const char *pMaterialName, bool &bUsesAlpha, bool &bIsCompressed, int &nSizeInBytes )
{
nSizeInBytes = 0;
bUsesAlpha = false;
if ( IsX360() )
{
// not supporting
return false;
}
// Special textures start with '_'..
if ( !pTextureName || ( pTextureName[0] == '_' ) || ( pTextureName[0] == 0 ) )
return false;
// The texture name doubles as the relative file name
// It's assumed to have already been set by this point
// Compute the cache name
char pCacheFileName[MATERIAL_MAX_PATH];
Q_snprintf( pCacheFileName, sizeof( pCacheFileName ), "materials/%s.vtf", pTextureName );
CUtlBuffer buf;
FileHandle_t fileHandle = g_pFullFileSystem->Open( pCacheFileName, "rb" );
if ( fileHandle == FILESYSTEM_INVALID_HANDLE)
{
// Warning( "Material \"%s\": can't open texture \"%s\"\n", pMaterialName, pCacheFileName );
return false;
}
// Check the .vtf for an alpha channel
IVTFTexture *pVTFTexture = CreateVTFTexture();
int nHeaderSize = VTFFileHeaderSize( VTF_MAJOR_VERSION );
buf.EnsureCapacity( nHeaderSize );
// read the header first.. it's faster!!
g_pFullFileSystem->Read( buf.Base(), nHeaderSize, fileHandle );
buf.SeekPut( CUtlBuffer::SEEK_HEAD, nHeaderSize );
// Unserialize the header
bool bUsesNormal = false;
if ( !pVTFTexture->Unserialize( buf, true ) )
{
Warning( "Error reading material \"%s\"\n", pCacheFileName );
}
else
{
if ( pVTFTexture->Flags() & TEXTUREFLAGS_NORMAL )
{
bUsesAlpha = false;
bUsesNormal = true;
bIsCompressed = ImageLoader::IsCompressed( pVTFTexture->Format() ) || ( pVTFTexture->Format() == IMAGE_FORMAT_A8 );
nSizeInBytes = pVTFTexture->ComputeTotalSize();
if ( pVTFTexture->Flags() & (TEXTUREFLAGS_ONEBITALPHA | TEXTUREFLAGS_EIGHTBITALPHA) )
{
bUsesAlpha = true;
}
}
}
DestroyVTFTexture( pVTFTexture );
g_pFullFileSystem->Close( fileHandle );
return bUsesNormal;
}
