/// <summary>
/// Loads a DDS texture from an input stream.
/// </summary>
public static Texture2DInfo LoadDDSTexture(Stream inputStream, bool flipVertically = false)
{
using (var reader = new UnityBinaryReader(inputStream))
{
// Check the magic string.
var magicString = reader.ReadBytes(4);
if (!StringUtils.Equals(magicString, "DDS "))
{
throw new FileFormatException("Invalid DDS file magic string: \"" + System.Text.Encoding.ASCII.GetString(magicString) + "\".");
}
// Deserialize the DDS file header.
var header = new DDSHeader();
header.Deserialize(reader);
// Figure out the texture format and load the texture data.
bool hasMipmaps;
uint DDSMipmapLevelCount;
TextureFormat textureFormat;
int bytesPerPixel;
byte[] textureData;
ExtractDDSTextureFormatAndData(header, reader, out hasMipmaps, out DDSMipmapLevelCount, out textureFormat, out bytesPerPixel, out textureData);
// Post-process the texture to generate missing mipmaps and possibly flip it vertically.
PostProcessDDSTexture((int)header.dwWidth, (int)header.dwHeight, bytesPerPixel, hasMipmaps, (int)DDSMipmapLevelCount, textureData, flipVertically);
return(new Texture2DInfo((int)header.dwWidth, (int)header.dwHeight, textureFormat, hasMipmaps, textureData));
}
}
/// <summary>
/// Extracts a DDS file's texture format and pixel data.
/// </summary>
private static void ExtractDDSTextureFormatAndData(DDSHeader header, UnityBinaryReader reader, out bool hasMipmaps, out uint DDSMipmapLevelCount, out TextureFormat textureFormat, out int bytesPerPixel, out byte[] textureData)
{
hasMipmaps = Utils.ContainsBitFlags(header.dwCaps, (uint)DDSCaps.Mipmap);
// Non-mipmapped textures still have one mipmap level: the texture itself.
DDSMipmapLevelCount = hasMipmaps ? header.dwMipMapCount : 1;
// If the DDS file contains uncompressed data.
if (Utils.ContainsBitFlags(header.pixelFormat.flags, (uint)DDSPixelFormatFlags.RGB))
{
// some permutation of RGB
if (!Utils.ContainsBitFlags(header.pixelFormat.flags, (uint)DDSPixelFormatFlags.AlphaPixels))
{
throw new NotImplementedException("Unsupported DDS file pixel format.");
}
// some permutation of RGBA
else
{
// There should be 32 bits per pixel.
if (header.pixelFormat.RGBBitCount != 32)
{
throw new FileFormatException("Invalid DDS file pixel format.");
}
// BGRA32
if ((header.pixelFormat.BBitMask == 0x000000FF) && (header.pixelFormat.GBitMask == 0x0000FF00) && (header.pixelFormat.RBitMask == 0x00FF0000) && (header.pixelFormat.ABitMask == 0xFF000000))
{
textureFormat = TextureFormat.BGRA32;
bytesPerPixel = 4;
}
// ARGB32
else if ((header.pixelFormat.ABitMask == 0x000000FF) && (header.pixelFormat.RBitMask == 0x0000FF00) && (header.pixelFormat.GBitMask == 0x00FF0000) && (header.pixelFormat.BBitMask == 0xFF000000))
{
textureFormat = TextureFormat.ARGB32;
bytesPerPixel = 4;
}
else
{
throw new NotImplementedException("Unsupported DDS file pixel format.");
}
if (!hasMipmaps)
{
textureData = new byte[header.dwPitchOrLinearSize * header.dwHeight];
}
else
{
// Create a data buffer to hold all mipmap levels down to 1x1.
textureData = new byte[TextureUtils.CalculateMipMappedTextureDataSize((int)header.dwWidth, (int)header.dwHeight, bytesPerPixel)];
}
reader.ReadRestOfBytes(textureData, 0);
}
}
else if (StringUtils.Equals(header.pixelFormat.fourCC, "DXT1"))
{
textureFormat = TextureFormat.ARGB32;
bytesPerPixel = 4;
var compressedTextureData = reader.ReadRestOfBytes();
textureData = DecodeDXT1ToARGB(compressedTextureData, header.dwWidth, header.dwHeight, header.pixelFormat, DDSMipmapLevelCount);
}
else if (StringUtils.Equals(header.pixelFormat.fourCC, "DXT3"))
{
textureFormat = TextureFormat.ARGB32;
bytesPerPixel = 4;
var compressedTextureData = reader.ReadRestOfBytes();
textureData = DecodeDXT3ToARGB(compressedTextureData, header.dwWidth, header.dwHeight, header.pixelFormat, DDSMipmapLevelCount);
}
else if (StringUtils.Equals(header.pixelFormat.fourCC, "DXT5"))
{
textureFormat = TextureFormat.ARGB32;
bytesPerPixel = 4;
var compressedTextureData = reader.ReadRestOfBytes();
textureData = DecodeDXT5ToARGB(compressedTextureData, header.dwWidth, header.dwHeight, header.pixelFormat, DDSMipmapLevelCount);
}
else
{
throw new NotImplementedException("Unsupported DDS file pixel format.");
}
}
/// <summary>
/// Extracts a DDS file's texture format and pixel data.
/// </summary>
private static void ExtractDDSTextureFormatAndData(DDSHeader header, UnityBinaryReader reader, out bool hasMipmaps, out uint DDSMipmapLevelCount, out TextureFormat textureFormat, out int bytesPerPixel, out byte[] textureData)
{
hasMipmaps = Utils.ContainsBitFlags(header.dwCaps, (uint)DDSCaps.Mipmap);
// Non-mipmapped textures still have one mipmap level: the texture itself.
DDSMipmapLevelCount = hasMipmaps ? header.dwMipMapCount : 1;
// If the DDS file contains uncompressed data.
if(Utils.ContainsBitFlags(header.pixelFormat.flags, (uint)DDSPixelFormatFlags.RGB))
{
// some permutation of RGB
if(!Utils.ContainsBitFlags(header.pixelFormat.flags, (uint)DDSPixelFormatFlags.AlphaPixels))
{
throw new NotImplementedException("Unsupported DDS file pixel format.");
}
// some permutation of RGBA
else
{
// There should be 32 bits per pixel.
if(header.pixelFormat.RGBBitCount != 32)
{
throw new FileFormatException("Invalid DDS file pixel format.");
}
// BGRA32
if((header.pixelFormat.BBitMask == 0x000000FF) && (header.pixelFormat.GBitMask == 0x0000FF00) && (header.pixelFormat.RBitMask == 0x00FF0000) && (header.pixelFormat.ABitMask == 0xFF000000))
{
textureFormat = TextureFormat.BGRA32;
bytesPerPixel = 4;
}
// ARGB32
else if((header.pixelFormat.ABitMask == 0x000000FF) && (header.pixelFormat.RBitMask == 0x0000FF00) && (header.pixelFormat.GBitMask == 0x00FF0000) && (header.pixelFormat.BBitMask == 0xFF000000))
{
textureFormat = TextureFormat.ARGB32;
bytesPerPixel = 4;
}
else
{
throw new NotImplementedException("Unsupported DDS file pixel format.");
}
if(!hasMipmaps)
{
textureData = new byte[header.dwPitchOrLinearSize * header.dwHeight];
}
else
{
// Create a data buffer to hold all mipmap levels down to 1x1.
textureData = new byte[TextureUtils.CalculateMipMappedTextureDataSize((int)header.dwWidth, (int)header.dwHeight, bytesPerPixel)];
}
reader.ReadRestOfBytes(textureData, 0);
}
}
else if(StringUtils.Equals(header.pixelFormat.fourCC, "DXT1"))
{
textureFormat = TextureFormat.ARGB32;
bytesPerPixel = 4;
var compressedTextureData = reader.ReadRestOfBytes();
textureData = DecodeDXT1ToARGB(compressedTextureData, header.dwWidth, header.dwHeight, header.pixelFormat, DDSMipmapLevelCount);
}
else if(StringUtils.Equals(header.pixelFormat.fourCC, "DXT3"))
{
textureFormat = TextureFormat.ARGB32;
bytesPerPixel = 4;
var compressedTextureData = reader.ReadRestOfBytes();
textureData = DecodeDXT3ToARGB(compressedTextureData, header.dwWidth, header.dwHeight, header.pixelFormat, DDSMipmapLevelCount);
}
else if(StringUtils.Equals(header.pixelFormat.fourCC, "DXT5"))
{
textureFormat = TextureFormat.ARGB32;
bytesPerPixel = 4;
var compressedTextureData = reader.ReadRestOfBytes();
textureData = DecodeDXT5ToARGB(compressedTextureData, header.dwWidth, header.dwHeight, header.pixelFormat, DDSMipmapLevelCount);
}
else
{
throw new NotImplementedException("Unsupported DDS file pixel format.");
}
}
/// <summary>
/// Loads a DDS texture from an input stream.
/// </summary>
public static Texture2DInfo LoadDDSTexture(Stream inputStream, bool flipVertically = false)
{
using(var reader = new UnityBinaryReader(inputStream))
{
// Check the magic string.
var magicString = reader.ReadBytes(4);
if(!StringUtils.Equals(magicString, "DDS "))
{
throw new FileFormatException("Invalid DDS file magic string: \"" + System.Text.Encoding.ASCII.GetString(magicString) + "\".");
}
// Deserialize the DDS file header.
var header = new DDSHeader();
header.Deserialize(reader);
// Figure out the texture format and load the texture data.
bool hasMipmaps;
uint DDSMipmapLevelCount;
TextureFormat textureFormat;
int bytesPerPixel;
byte[] textureData;
ExtractDDSTextureFormatAndData(header, reader, out hasMipmaps, out DDSMipmapLevelCount, out textureFormat, out bytesPerPixel, out textureData);
// Post-process the texture to generate missing mipmaps and possibly flip it vertically.
PostProcessDDSTexture((int)header.dwWidth, (int)header.dwHeight, bytesPerPixel, hasMipmaps, (int)DDSMipmapLevelCount, textureData, flipVertically);
return new Texture2DInfo((int)header.dwWidth, (int)header.dwHeight, textureFormat, hasMipmaps, textureData);
}
}
