/// <summary>
/// Reads DDS format from DDS Header.
/// Not guaranteed to work. Format 'optional' in header.
/// </summary>
/// <param name="stream">Stream containing full image file. NOT just pixels.</param>
/// <param name="header">DDS Header information.</param>
/// <returns>Format of DDS.</returns>
internal static Format ParseDDSFormat(Stream stream, out DDS_HEADER header)
{
Format format = new Format(ImageEngineFormat.DDS_ARGB);
stream.Seek(0, SeekOrigin.Begin);
using (BinaryReader reader = new BinaryReader(stream, Encoding.Default, true))
{
header = null;
// KFreon: Check image is a DDS
int Magic = reader.ReadInt32();
if (Magic != 0x20534444)
{
return(new Format()); // KFreon: Not a DDS
}
header = new DDS_HEADER();
Read_DDS_HEADER(header, reader);
if (((header.ddspf.dwFlags & 0x00000004) != 0) && (header.ddspf.dwFourCC == 0x30315844 /*DX10*/))
{
throw new Exception("DX10 not supported yet!");
}
format = ImageFormats.ParseFourCC(header.ddspf.dwFourCC);
if (format.SurfaceFormat == ImageEngineFormat.Unknown || format.SurfaceFormat == ImageEngineFormat.DDS_ARGB)
{
// KFreon: Apparently all these flags mean it's a V8U8 image...
if (header.ddspf.dwRGBBitCount == 0x10 &&
header.ddspf.dwRBitMask == 0xFF &&
header.ddspf.dwGBitMask == 0xFF00 &&
header.ddspf.dwBBitMask == 0x00 &&
header.ddspf.dwABitMask == 0x00)
{
format = new Format(ImageEngineFormat.DDS_V8U8); // KFreon: V8U8
}
// KFreon: Test for L8/G8
else if (header.ddspf.dwABitMask == 0 &&
header.ddspf.dwBBitMask == 0 &&
header.ddspf.dwGBitMask == 0 &&
header.ddspf.dwRBitMask == 255 &&
header.ddspf.dwFlags == 131072 &&
header.ddspf.dwSize == 32 &&
header.ddspf.dwRGBBitCount == 8)
{
format = new Format(ImageEngineFormat.DDS_G8_L8);
}
// KFreon: A8L8. This can probably be something else as well, but it seems to work for now
else if (header.ddspf.dwRGBBitCount == 16)
{
format = new Format(ImageEngineFormat.DDS_A8L8);
}
// KFreon: RGB test.
else if (header.ddspf.dwRGBBitCount == 24)
{
format = new Format(ImageEngineFormat.DDS_RGB);
}
}
}
return(format);
}
