/// <summary>
/// Provides a configured LinearGradient that can be used in combination with a GradientImageSource to provide a mask for the LensBlurEffect.
/// It will expect the LensBlur will be blurred with 1 kernel when the double is different from None.
/// </summary>
/// <param name="ellipse">The band that represents the focus area in the image. Pixels within this band won't be blurred.
/// Areas outside of the area will be progressively more blurred as the distance from the focus band increases.</param>
/// <param name="strength">Strength of the blur.</param>
/// <returns>A LinearGradient that can be used in combination with a GradientImageSource to be used by LensBlur.</returns>
public static RadialGradient GenerateGradient(FocusEllipse ellipse, KernelGenerator kernelGenerator)
{
if (kernelGenerator.GetKernelBands().Count == 0)
{
return(null);
}
EllipseRadius maxBlurRadius = null;
if ((ellipse.Radius.X < minDiffBetweenStops) && (ellipse.Radius.Y < minDiffBetweenStops))
{
maxBlurRadius = new EllipseRadius(minDiffBetweenStops, minDiffBetweenStops);
}
else
{
double factor = 0.9;
bool widthGtHight = ellipse.Radius.X > ellipse.Radius.Y;
if (widthGtHight)
{
maxBlurRadius = new EllipseRadius(factor, factor * ellipse.Radius.Y / ellipse.Radius.X);
}
else
{
maxBlurRadius = new EllipseRadius(factor * ellipse.Radius.X / ellipse.Radius.Y, factor);
}
}
var gradient = new RadialGradient(ellipse.Center, maxBlurRadius);
SetGradientStops(gradient, ellipse, maxBlurRadius, kernelGenerator);
return(gradient);
}
/// <summary>
/// Provides a configured LinearGradient that can be used in combination with a GradientImageSource to provide a mask for the LensBlurEffect.
/// It will expect the LensBlur will be blurred with 1 kernel when the double is different from None.
/// </summary>
/// <param name="ellipse">The band that represents the focus area in the image. Pixels within this band won't be blurred.
/// Areas outside of the area will be progressively more blurred as the distance from the focus band increases.</param>
/// <param name="strength">Strength of the blur.</param>
/// <returns>A LinearGradient that can be used in combination with a GradientImageSource to be used by LensBlur.</returns>
public static RadialGradient GenerateGradient(FocusEllipse ellipse, KernelGenerator kernelGenerator)
{
if (kernelGenerator.GetKernelBands().Count == 0)
{
return null;
}
EllipseRadius maxBlurRadius = null;
if ((ellipse.Radius.X < minDiffBetweenStops) && (ellipse.Radius.Y < minDiffBetweenStops))
{
maxBlurRadius = new EllipseRadius(minDiffBetweenStops, minDiffBetweenStops);
}
else
{
double factor = 0.9;
bool widthGtHight = ellipse.Radius.X > ellipse.Radius.Y;
if (widthGtHight)
{
maxBlurRadius = new EllipseRadius(factor, factor * ellipse.Radius.Y / ellipse.Radius.X);
}
else
{
maxBlurRadius = new EllipseRadius(factor * ellipse.Radius.X / ellipse.Radius.Y, factor);
}
}
var gradient = new RadialGradient(ellipse.Center, maxBlurRadius);
SetGradientStops(gradient, ellipse, maxBlurRadius, kernelGenerator);
return gradient;
}
private static void SetGradientStops(LinearGradient gradient, FocusBand focusBand, Size sourceSize, KernelGenerator edge1KernelGenerator, KernelGenerator edge2KernelGenerator, bool applySmallBlurFocusArea)
{
var blurArea1FirstOffset = GetOffset(gradient, focusBand.Edge1);
var blurArea2FirstOffset = GetOffset(gradient, focusBand.Edge2);
var focusBandEdge1Pixels = new Point(focusBand.Edge1.X * sourceSize.Width, focusBand.Edge1.Y * sourceSize.Height);
var focusBandEdge2Pixels = new Point(focusBand.Edge2.X * sourceSize.Width, focusBand.Edge2.Y * sourceSize.Height);
var focusBandWidth = Math.Abs(blurArea1FirstOffset - blurArea2FirstOffset);
var focusBandWidthPixels = Distance(focusBandEdge1Pixels, focusBandEdge2Pixels);
double blurAreaWidth;
if (focusBandWidthPixels > 0)
{
var scaleFactor = focusBandWidth / focusBandWidthPixels;
var blurAreaWidthPixels = (sourceSize.Height - focusBandWidthPixels) / 2 * 0.9;
if (blurAreaWidthPixels < 1.0)
{
gradient.Stops = new[] { new GradientStop() { Offset = 0.5, Color = Color.FromArgb(255, 0, 0, 0) } };
return;
}
blurAreaWidth = blurAreaWidthPixels * scaleFactor;
}
else
{
blurAreaWidth = 0.5;
applySmallBlurFocusArea = true;
}
double blurArea1LastOffset;
double blurArea2LastOffset;
if (blurArea1FirstOffset > blurArea2FirstOffset)
{
blurArea1LastOffset = blurArea1FirstOffset + blurAreaWidth;
blurArea2LastOffset = blurArea2FirstOffset - blurAreaWidth;
}
else
{
blurArea1LastOffset = blurArea1FirstOffset - blurAreaWidth;
blurArea2LastOffset = blurArea2FirstOffset + blurAreaWidth;
}
var stops1 = GetGradientStops(gradient, applySmallBlurFocusArea, edge1KernelGenerator, blurArea1FirstOffset, blurArea1LastOffset);
var stops2 = GetGradientStops(gradient, applySmallBlurFocusArea, edge2KernelGenerator, blurArea2FirstOffset, blurArea2LastOffset, (byte)(edge1KernelGenerator.GetKernelBands().Count));
List<GradientStop> stops = new List<GradientStop>();
stops.AddRange(stops1);
stops.AddRange(stops2);
var validStops = EnsureMinDiffBetweenPoints(stops);
gradient.Stops = validStops.ToArray();
}
/// <summary>
/// Provides a configured LinearGradient that can be used in combination with a GradientImageSource to provide a mask for the LensBlurEffect.
/// Generates a map for BlendEffect.
/// </summary>
/// <param name="band">The band that represents the focus area in the image. Pixels within this band won't be blurred.
/// Areas outside of the area will be progressively more blurred as the distance from the focus band increases.</param>
/// <param name="kernelSpanFromEdge1">Strength at Edge1.</param>
/// <param name="kernelSpanFromEdge2">Strength at Edge2.</param>
/// <returns>A LinearGradient that can be used in combination with a GradientImageSource to be used by LensBlur.</returns>
public static LinearGradient GenerateGradient(FocusBand band, Size sourceSize, KernelGenerator edge1KernelGenerator, KernelGenerator edge2KernelGenerator, bool applySmallBlurFocusArea)
{
var gradient = new LinearGradient();
var lineFunction = GradientLine.CreateFunction(band);
SetGradientPoints(gradient, lineFunction);
SetGradientStops(gradient, band, sourceSize, edge1KernelGenerator, edge2KernelGenerator, applySmallBlurFocusArea);
return gradient;
}
private static void SetGradientStops(RadialGradient gradient, FocusEllipse ellipse, EllipseRadius maxBlurRadius, KernelGenerator kernelGenerator)
{
var stops = new List<GradientStop>();
double firstStopOffset;
if (maxBlurRadius.X > minDiffBetweenStops)
{
firstStopOffset = ellipse.Radius.X / maxBlurRadius.X;
//Add the focus area at the center of the ellipse.
stops.Add(new GradientStop() { Color = Color.FromArgb(255, 0, 0, 0), Offset = 0 });
stops.Add(new GradientStop() { Color = Color.FromArgb(255, 0, 0, 0), Offset = firstStopOffset });
}
else
{
firstStopOffset = minDiffBetweenStops;
}
double sumOfBandWidths = kernelGenerator.GetKernelBands().Select(band => band.Width).Sum();
var currentStopOffset = firstStopOffset + minDiffBetweenStops;
var kernelBands = kernelGenerator.GetKernelBands();
byte kernelIndex = 0;
foreach (var band in kernelBands)
{
kernelIndex++;
stops.Add(new GradientStop() { Color = Color.FromArgb(255, kernelIndex, kernelIndex, kernelIndex), Offset = currentStopOffset });
currentStopOffset = currentStopOffset + (band.Width / sumOfBandWidths) * (1 - firstStopOffset) * FocusToBlurTransitionWidth;
}
stops.Add(new GradientStop() { Color = Color.FromArgb(255, kernelIndex, kernelIndex, kernelIndex), Offset = currentStopOffset });
var validStops = EnsureMinDiffBetweenPoints(stops);
gradient.Stops = validStops.ToArray();
}
private static void SetGradientStops(LinearGradient gradient, FocusBand focusBand, Size sourceSize, KernelGenerator edge1KernelGenerator, KernelGenerator edge2KernelGenerator, bool applySmallBlurFocusArea)
{
var blurArea1FirstOffset = GetOffset(gradient, focusBand.Edge1);
var blurArea2FirstOffset = GetOffset(gradient, focusBand.Edge2);
var focusBandEdge1Pixels = new Point(focusBand.Edge1.X * sourceSize.Width, focusBand.Edge1.Y * sourceSize.Height);
var focusBandEdge2Pixels = new Point(focusBand.Edge2.X * sourceSize.Width, focusBand.Edge2.Y * sourceSize.Height);
var focusBandWidth = Math.Abs(blurArea1FirstOffset - blurArea2FirstOffset);
var focusBandWidthPixels = Distance(focusBandEdge1Pixels, focusBandEdge2Pixels);
double blurAreaWidth;
if (focusBandWidthPixels > 0)
{
var scaleFactor = focusBandWidth / focusBandWidthPixels;
var blurAreaWidthPixels = (sourceSize.Height - focusBandWidthPixels) / 2 * 0.9;
if (blurAreaWidthPixels < 1.0)
{
gradient.Stops = new[] { new GradientStop()
{
Offset = 0.5, Color = Color.FromArgb(255, 0, 0, 0)
} };
return;
}
blurAreaWidth = blurAreaWidthPixels * scaleFactor;
}
else
{
blurAreaWidth = 0.5;
applySmallBlurFocusArea = true;
}
double blurArea1LastOffset;
double blurArea2LastOffset;
if (blurArea1FirstOffset > blurArea2FirstOffset)
{
blurArea1LastOffset = blurArea1FirstOffset + blurAreaWidth;
blurArea2LastOffset = blurArea2FirstOffset - blurAreaWidth;
}
else
{
blurArea1LastOffset = blurArea1FirstOffset - blurAreaWidth;
blurArea2LastOffset = blurArea2FirstOffset + blurAreaWidth;
}
var stops1 = GetGradientStops(gradient, applySmallBlurFocusArea, edge1KernelGenerator, blurArea1FirstOffset, blurArea1LastOffset);
var stops2 = GetGradientStops(gradient, applySmallBlurFocusArea, edge2KernelGenerator, blurArea2FirstOffset, blurArea2LastOffset, (byte)(edge1KernelGenerator.GetKernelBands().Count));
List <GradientStop> stops = new List <GradientStop>();
stops.AddRange(stops1);
stops.AddRange(stops2);
var validStops = EnsureMinDiffBetweenPoints(stops);
gradient.Stops = validStops.ToArray();
}
/// <summary>
/// Provides a configured LinearGradient that can be used in combination with a GradientImageSource to provide a mask for the LensBlurEffect.
/// Generates a map for BlendEffect.
/// </summary>
/// <param name="band">The band that represents the focus area in the image. Pixels within this band won't be blurred.
/// Areas outside of the area will be progressively more blurred as the distance from the focus band increases.</param>
/// <param name="kernelSpanFromEdge1">Strength at Edge1.</param>
/// <param name="kernelSpanFromEdge2">Strength at Edge2.</param>
/// <returns>A LinearGradient that can be used in combination with a GradientImageSource to be used by LensBlur.</returns>
public static LinearGradient GenerateGradient(FocusBand band, Size sourceSize, KernelGenerator edge1KernelGenerator, KernelGenerator edge2KernelGenerator, bool applySmallBlurFocusArea)
{
var gradient = new LinearGradient();
var lineFunction = GradientLine.CreateFunction(band);
SetGradientPoints(gradient, lineFunction);
SetGradientStops(gradient, band, sourceSize, edge1KernelGenerator, edge2KernelGenerator, applySmallBlurFocusArea);
return(gradient);
}
private static List <GradientStop> GetGradientStops(LinearGradient gradient, bool applySmallBlurFocusArea, KernelGenerator kernelGenerator, double firstStopOffset, double lastStopOffset, byte firstKernelIndex = 0)
{
var stops = new List <GradientStop>();
if (kernelGenerator.GetKernelBands().Count > 0)
{
double sumOfBandWidths = kernelGenerator.GetKernelBands().Select(band => band.Width).Sum();
var focusAreaColor = GetFocusAreaColor(applySmallBlurFocusArea);
stops.Add(new GradientStop()
{
Color = Color.FromArgb(255, focusAreaColor, focusAreaColor, focusAreaColor), Offset = firstStopOffset
});
var currentStopOffset = lastStopOffset - firstStopOffset > 0
? firstStopOffset + minDiffBetweenStops
: firstStopOffset - minDiffBetweenStops;
var kernelBands = kernelGenerator.GetKernelBands();
byte kernelIndex = firstKernelIndex;
foreach (var band in kernelBands)
{
kernelIndex++;
stops.Add(new GradientStop()
{
Color = Color.FromArgb(255, kernelIndex, kernelIndex, kernelIndex), Offset = currentStopOffset
});
currentStopOffset = currentStopOffset + (band.Width / sumOfBandWidths) * (lastStopOffset - firstStopOffset) * FocusToBlurTransitionWidth;
}
stops.Add(new GradientStop()
{
Color = Color.FromArgb(255, kernelIndex, kernelIndex, kernelIndex), Offset = currentStopOffset
});
stops = EnsureMinDiffBetweenPoints(stops);
}
return(stops);
}
private static void SetGradientStops(RadialGradient gradient, FocusEllipse ellipse, EllipseRadius maxBlurRadius, KernelGenerator kernelGenerator)
{
var stops = new List <GradientStop>();
double firstStopOffset;
if (maxBlurRadius.X > minDiffBetweenStops)
{
firstStopOffset = ellipse.Radius.X / maxBlurRadius.X;
//Add the focus area at the center of the ellipse.
stops.Add(new GradientStop()
{
Color = Color.FromArgb(255, 0, 0, 0), Offset = 0
});
stops.Add(new GradientStop()
{
Color = Color.FromArgb(255, 0, 0, 0), Offset = firstStopOffset
});
}
else
{
firstStopOffset = minDiffBetweenStops;
}
double sumOfBandWidths = kernelGenerator.GetKernelBands().Select(band => band.Width).Sum();
var currentStopOffset = firstStopOffset + minDiffBetweenStops;
var kernelBands = kernelGenerator.GetKernelBands();
byte kernelIndex = 0;
foreach (var band in kernelBands)
{
kernelIndex++;
stops.Add(new GradientStop()
{
Color = Color.FromArgb(255, kernelIndex, kernelIndex, kernelIndex), Offset = currentStopOffset
});
currentStopOffset = currentStopOffset + (band.Width / sumOfBandWidths) * (1 - firstStopOffset) * FocusToBlurTransitionWidth;
}
stops.Add(new GradientStop()
{
Color = Color.FromArgb(255, kernelIndex, kernelIndex, kernelIndex), Offset = currentStopOffset
});
var validStops = EnsureMinDiffBetweenPoints(stops);
gradient.Stops = validStops.ToArray();
}
private static List<GradientStop> GetGradientStops(LinearGradient gradient, bool applySmallBlurFocusArea, KernelGenerator kernelGenerator, double firstStopOffset, double lastStopOffset, byte firstKernelIndex = 0)
{
var stops = new List<GradientStop>();
if (kernelGenerator.GetKernelBands().Count > 0)
{
double sumOfBandWidths = kernelGenerator.GetKernelBands().Select(band => band.Width).Sum();
var focusAreaColor = GetFocusAreaColor(applySmallBlurFocusArea);
stops.Add(new GradientStop() { Color = Color.FromArgb(255, focusAreaColor, focusAreaColor, focusAreaColor), Offset = firstStopOffset });
var currentStopOffset = lastStopOffset - firstStopOffset > 0
? firstStopOffset + minDiffBetweenStops
: firstStopOffset - minDiffBetweenStops;
var kernelBands = kernelGenerator.GetKernelBands();
byte kernelIndex = firstKernelIndex;
foreach (var band in kernelBands)
{
kernelIndex++;
stops.Add(new GradientStop() { Color = Color.FromArgb(255, kernelIndex, kernelIndex, kernelIndex), Offset = currentStopOffset });
currentStopOffset = currentStopOffset + (band.Width / sumOfBandWidths) * (lastStopOffset - firstStopOffset) * FocusToBlurTransitionWidth;
}
stops.Add(new GradientStop() { Color = Color.FromArgb(255, kernelIndex, kernelIndex, kernelIndex), Offset = currentStopOffset });
stops = EnsureMinDiffBetweenPoints(stops);
}
return stops;
}