/// <summary>
/// See <see cref="BaseColorDitherer.OnProcessPixel"/> for more details.
/// </summary>
protected override Boolean OnProcessPixel(Pixel sourcePixel, Pixel targetPixel)
{
// reads the source pixel
Color oldColor = SourceBuffer.GetColorFromPixel(sourcePixel);
// converts alpha to solid color
oldColor = QuantizationHelper.ConvertAlpha(oldColor);
// retrieves matrix coordinates
Int32 x = targetPixel.X % MatrixWidth;
Int32 y = targetPixel.Y % MatrixHeight;
// determines the threshold
Int32 threshold = Convert.ToInt32(CachedMatrix[x, y]);
// only process dithering if threshold is substantial
if (threshold > 0)
{
Int32 red = GetClampedColorElement(oldColor.R + threshold);
Int32 green = GetClampedColorElement(oldColor.G + threshold);
Int32 blue = GetClampedColorElement(oldColor.B + threshold);
Color newColor = Color.FromArgb(255, red, green, blue);
if (TargetBuffer.IsIndexed)
{
Byte newPixelIndex = (Byte)Quantizer.GetPaletteIndex(newColor, targetPixel.X, targetPixel.Y);
targetPixel.Index = newPixelIndex;
}
else
{
targetPixel.Color = newColor;
}
}
// writes the process pixel
return(true);
}