public override BitmapBase Apply(RenderTask renderTask, BitmapBase layer)
{
Tank tank = renderTask.Tank;
if (Strength == 0)
{
return(layer);
}
int totalAlpha = 0;
long totalBrightness = 0;
using (layer.UseRead())
unsafe
{
for (int y = 0; y < layer.Height; y++)
{
byte *linePtr = layer.Data + y * layer.Stride;
byte *lineEndPtr = linePtr + layer.Width * 4;
while (linePtr < lineEndPtr)
{
int brightness = *(linePtr) * 722 + *(linePtr + 1) * 7152 + *(linePtr + 2) * 2126;
totalBrightness += brightness * *(linePtr + 3);
totalAlpha += *(linePtr + 3);
linePtr += 4;
}
}
}
if (totalAlpha == 0)
{
return(layer);
}
using (var image = layer.ToMagickImage())
{
var averageBrightness = (double)totalBrightness * 100.0 / (double)totalAlpha / 255.0 / 10000.0;
image.BackgroundColor = MagickColors.Transparent;
double strength = Strength / 100;
double scaleValue = 1 + (Brightness / averageBrightness - 1) * strength;
double scaleSaturation = Saturation == SaturationMode.Zero ? 0 : 1;
if (Saturation == SaturationMode.Reduce && scaleValue < 1)
{
scaleSaturation = 1 - (1 - scaleValue * scaleValue) * strength;
}
image.Modulate(new Percentage(100 * scaleValue), new Percentage(100 * scaleSaturation), new Percentage(100));
layer.CopyPixelsFrom(image.ToBitmapSource());
return(layer);
}
}
