/// <summary>
/// Encodes an image into the BC2 format.
/// </summary>
/// <param name="image">The image to encode.</param>
/// <param name="rChan">The channel to pull red values from.</param>
/// <param name="gChan">The channel to pull green values from.</param>
/// <param name="bChan">The channel to pull blue values from.</param>
/// <param name="aChan">The channel to pull alpha values from.</param>
/// <returns>The encoded BC2 image data.</returns>
public BCnImage <BC2Block> EncodeBC2(FloatImage image,
int rChan = 0, int gChan = 1, int bChan = 2, int aChan = 3)
{
if (image == null)
{
throw new ArgumentNullException("image");
}
if (rChan < 0 || rChan >= image.ChannelCount)
{
throw new ArgumentOutOfRangeException("rChan");
}
if (gChan < 0 || gChan >= image.ChannelCount)
{
throw new ArgumentOutOfRangeException("gChan");
}
if (bChan < 0 || bChan >= image.ChannelCount)
{
throw new ArgumentOutOfRangeException("bChan");
}
if (aChan < 0 || aChan >= image.ChannelCount)
{
throw new ArgumentOutOfRangeException("aChan");
}
var ret = new BCnImage <BC2Block>(image.Width, image.Height);
ImageEncodingHelper.EncodeBlocks(ret,
() =>
{
var encBC1 = new BC1BlockEncoder();
var encBC2A = new BC2ABlockEncoder();
encBC1.DitherRgb = DitherRgb;
encBC2A.Dither = DitherAlpha;
return((chanData, index, pitch) =>
{
encBC1.LoadBlock(
chanData[0], index,
chanData[1], index,
chanData[2], index,
pitch);
encBC2A.LoadBlock(chanData[3], index, pitch);
BC2Block block;
block.Rgb = encBC1.Encode();
block.A = encBC2A.Encode();
return block;
});
},
image, new int[] { rChan, gChan, bChan, aChan });
return(ret);
}
private BCnImage <BC1Block> InternalEncodeBC1(FloatImage image,
int rChan, int gChan, int bChan, int aChan)
{
if (image == null)
{
throw new ArgumentNullException("image");
}
if (rChan < 0 || rChan >= image.ChannelCount)
{
throw new ArgumentOutOfRangeException("rChan");
}
if (gChan < 0 || gChan >= image.ChannelCount)
{
throw new ArgumentOutOfRangeException("gChan");
}
if (bChan < 0 || bChan >= image.ChannelCount)
{
throw new ArgumentOutOfRangeException("bChan");
}
if (aChan != -1 && (aChan < 0 || aChan >= image.ChannelCount))
{
throw new ArgumentOutOfRangeException("aChan");
}
var ret = new BCnImage <BC1Block>(image.Width, image.Height);
ImageEncodingHelper.EncodeBlocks(ret,
() =>
{
var encBC1 = new BC1BlockEncoder();
encBC1.DitherRgb = DitherRgb;
encBC1.DitherAlpha = DitherAlpha;
return((chanData, index, pitch) =>
{
encBC1.LoadBlock(
chanData[0], index,
chanData[1], index,
chanData[2], index,
pitch);
if (chanData[3] != null)
{
encBC1.LoadAlphaMask(chanData[3], index, 0.5F, pitch);
}
return encBC1.Encode();
});
},
image, new int[] { rChan, gChan, bChan, aChan });
return(ret);
}