// Note that many common DDS reader/writers (including D3DX) swap the
// the RED/BLUE masks for 10:10:10:2 formats. We assume
// below that the 'backwards' header mask is being used since it is most
// likely written by D3DX. The more robust solution is to use the 'DX10'
// header extension and specify the Format.R10G10B10A2_UNorm format directly
// We do not support the following legacy Direct3D 9 formats:
// BumpDuDv D3DFMT_V8U8, D3DFMT_Q8W8V8U8, D3DFMT_V16U16, D3DFMT_A2W10V10U10
// BumpLuminance D3DFMT_L6V5U5, D3DFMT_X8L8V8U8
// FourCC "UYVY" D3DFMT_UYVY
// FourCC "YUY2" D3DFMT_YUY2
// FourCC 117 D3DFMT_CxV8U8
// ZBuffer D3DFMT_D16_LOCKABLE
// FourCC 82 D3DFMT_D32F_LOCKABLE
private static DXGI.Format GetDXGIFormat(ref DDS.PixelFormat pixelFormat, DDSFlags flags, out ConversionFlags conversionFlags)
{
conversionFlags = ConversionFlags.None;
int index = 0;
for (index = 0; index < LegacyMaps.Length; ++index)
{
var entry = LegacyMaps[index];
if ((pixelFormat.Flags & entry.PixelFormat.Flags) != 0)
{
if ((entry.PixelFormat.Flags & DDS.PixelFormatFlags.FourCC) != 0)
{
if (pixelFormat.FourCC == entry.PixelFormat.FourCC)
break;
}
else if ((entry.PixelFormat.Flags & DDS.PixelFormatFlags.Pal8) != 0)
{
if (pixelFormat.RGBBitCount == entry.PixelFormat.RGBBitCount)
break;
}
else if (pixelFormat.RGBBitCount == entry.PixelFormat.RGBBitCount)
{
// RGB, RGBA, ALPHA, LUMINANCE
if (pixelFormat.RBitMask == entry.PixelFormat.RBitMask
&& pixelFormat.GBitMask == entry.PixelFormat.GBitMask
&& pixelFormat.BBitMask == entry.PixelFormat.BBitMask
&& pixelFormat.ABitMask == entry.PixelFormat.ABitMask)
break;
}
}
}
if (index >= LegacyMaps.Length)
return DXGI.Format.Unknown;
conversionFlags = LegacyMaps[index].ConversionFlags;
var format = LegacyMaps[index].Format;
if ((conversionFlags & ConversionFlags.Expand) != 0 && (flags & DDSFlags.NoLegacyExpansion) != 0)
return DXGI.Format.Unknown;
if ((format == DXGI.Format.R10G10B10A2_UNorm) && (flags & DDSFlags.NoR10B10G10A2Fixup) != 0)
{
conversionFlags ^= ConversionFlags.Swizzle;
}
return format;
}
/// <summary>
/// Initializes a new instance of the <see cref="LegacyMap" /> struct.
/// </summary>
/// <param name="format">The format.</param>
/// <param name="conversionFlags">The conversion flags.</param>
/// <param name="pixelFormat">The pixel format.</param>
public LegacyMap(Format format, ConversionFlags conversionFlags, DDS.PixelFormat pixelFormat)
{
Format = format;
ConversionFlags = conversionFlags;
PixelFormat = pixelFormat;
}
