/// <summary>
/// Redraws the IImageMaskSurface using the alpha values of the image in the given IImageMaskSurface using the given padding
/// and options.
/// </summary>
/// <param name="imageMaskSurface">IImageMaskSurface whose image's alpha values are to be used to create the mask.</param>
/// <param name="padding">The padding between the IImageMaskSurface outer bounds and the bounds of the area where
/// the mask, created from the loaded image's alpha values, should be rendered.</param>
/// <param name="options">Describes the image's resize, alignment and blur radius options in the allocated space.</param>
public void Redraw(IImageMaskSurface imageMaskSurface, Thickness padding, ImageSurfaceOptions options)
{
if (imageMaskSurface != null)
{
Redraw(imageMaskSurface.SurfaceBitmap, imageMaskSurface.Size, padding, options);
}
else
{
// Draw an empty surface
Redraw(surfaceBitmap: null, Size, padding, options);
}
}
/// <summary>
/// Redraws the IImageMaskSurface using the alpha values of the image in the given IImageMaskSurface.
/// </summary>
/// <param name="imageMaskSurface">IImageMaskSurface whose image's alpha values are to be used to create the mask.</param>
public void Redraw(IImageMaskSurface imageMaskSurface)
{
if (imageMaskSurface != null)
{
Redraw(imageMaskSurface.SurfaceBitmap, imageMaskSurface.Size, imageMaskSurface.MaskPadding, imageMaskSurface.Options);
}
else
{
// Draw an empty surface
Redraw(surfaceBitmap: null, Size, MaskPadding, Options);
}
}
async void Redraw(bool recreateSurface = true)
{
if (_compositor == null)
{
_compositor = Window.Current.Compositor;
_generator = _compositor.CreateCompositionGenerator();
_defaultSize = new Vector2(GridWidth, GridWidth);
// Create the original output image visual
_originalImageVisual = _compositor.CreateSpriteVisual();
_originalImageVisual.Size = _defaultSize;
_imageSurface = await _generator.CreateImageSurfaceAsync(new Uri("ms-appx:///Assets/Images/cat.png"), _defaultSize.ToSize(), ImageSurfaceOptions.Default);
_originalImageVisual.Brush = _compositor.CreateSurfaceBrush(_imageSurface);
ElementCompositionPreview.SetElementChildVisual(OriginalOutputGrid, _originalImageVisual);
// Create the source image visual
_sourceImageVisual = _compositor.CreateSpriteVisual();
_sourceImageVisual.Size = _defaultSize;
ElementCompositionPreview.SetElementChildVisual(ImageGrid, _sourceImageVisual);
//Create the mask visual
_maskVisual = _compositor.CreateSpriteVisual();
_maskVisual.Size = _defaultSize;
ElementCompositionPreview.SetElementChildVisual(MaskGrid, _maskVisual);
// Create the output visual
_outputVisual = _compositor.CreateSpriteVisual();
_outputVisual.Size = _defaultSize;
ElementCompositionPreview.SetElementChildVisual(OutputGrid, _outputVisual);
}
var selIndex = ImageList.SelectedIndex;
if (selIndex == -1)
{
return;
}
var uri = _images.Values.ElementAt(selIndex);
if (uri == null)
{
return;
}
var offset = OffsetSlider.Value.ToSingle();
var padding = new Thickness(offset);
if (recreateSurface)
{
_sourceImageSurface =
await _generator.CreateImageSurfaceAsync(uri, _defaultSize.ToSize(), ImageSurfaceOptions.Default);
_imageMaskSurface = _generator.CreateImageMaskSurface(_sourceImageSurface, _defaultSize.ToSize(),
padding, ImageSurfaceOptions.GetDefaultImageMaskOptionsForBlur(_blurRadius));
}
else
{
_imageMaskSurface.Resize(_defaultSize.ToSize(), padding, ImageSurfaceOptions.GetDefaultImageMaskOptionsForBlur(_blurRadius));
}
_sourceImageVisual.Brush = _compositor.CreateSurfaceBrush(_sourceImageSurface);
_maskVisual.Brush = _compositor.CreateSurfaceBrush(_imageMaskSurface);
var maskedBrush = _compositor.CreateMaskBrush();
maskedBrush.Source = _originalImageVisual.Brush;
maskedBrush.Mask = _compositor.CreateSurfaceBrush(_imageMaskSurface);
_outputVisual.Brush = maskedBrush;
}
/// <summary>
/// Resizes and redraws the IImageMaskSurface using the alpha values of the image in the given IImageMaskSurface
/// with the given padding and options.
/// </summary>
/// <param name="imageMaskSurface">IImageMaskSurface whose image's alpha values are to be used to create the mask.</param>
/// <param name="size">New size of the IImageMaskSurface.</param>
/// <param name="padding">The padding between the IImageMaskSurface outer bounds and the bounds of the area where
/// the mask, created from the loaded image's alpha values, should be rendered.</param>
/// <param name="options">Describes the image's resize, alignment and blur radius options in the allocated space.</param>
public void Redraw(IImageMaskSurface imageMaskSurface, Size size, Thickness padding, ImageSurfaceOptions options)
{
Redraw(imageMaskSurface?.SurfaceBitmap, size, padding, options);
}
