public static Surface CombineLayers(Int32Rect portion, IEnumerable <Layer> layers, LayerStructure structure = null)
{
Surface finalSurface = new(portion.Width, portion.Height);
using SKPaint paint = new();
for (int i = 0; i < layers.Count(); i++)
{
Layer layer = layers.ElementAt(i);
if (structure != null && !LayerStructureUtils.GetFinalLayerIsVisible(layer, structure))
{
continue;
}
float layerOpacity = structure == null ? layer.Opacity : LayerStructureUtils.GetFinalLayerOpacity(layer, structure);
paint.Color = new(255, 255, 255, (byte)(layerOpacity * 255));
if (layer.OffsetX < 0 || layer.OffsetY < 0 ||
layer.Width + layer.OffsetX > layer.MaxWidth ||
layer.Height + layer.OffsetY > layer.MaxHeight)
{
throw new InvalidOperationException("Layers must not extend beyond canvas borders");
}
using SKImage snapshot = layer.LayerBitmap.SkiaSurface.Snapshot();
int x = portion.X - layer.OffsetX;
int y = portion.Y - layer.OffsetY;
finalSurface.SkiaSurface.Canvas.DrawImage(
snapshot,
new SKRect(x, y, portion.Width + x, portion.Height + y),
new SKRect(0, 0, portion.Width, portion.Height),
paint);
}
return(finalSurface);
}
/// <summary>
/// Converts layers bitmaps into one bitmap.
/// </summary>
/// <param name="width">Width of final bitmap.</param>
/// <param name="height">Height of final bitmap.</param>.
/// <param name="layers">Layers to combine.</param>
/// <returns>WriteableBitmap of layered bitmaps.</returns>
public static WriteableBitmap CombineLayers(int width, int height, IEnumerable <Layer> layers, LayerStructure structure = null)
{
WriteableBitmap finalBitmap = BitmapFactory.New(width, height);
using (finalBitmap.GetBitmapContext())
{
for (int i = 0; i < layers.Count(); i++)
{
Layer layer = layers.ElementAt(i);
float layerOpacity = structure == null ? layer.Opacity : LayerStructureUtils.GetFinalLayerOpacity(layer, structure);
if (layer.OffsetX < 0 || layer.OffsetY < 0 ||
layer.Width + layer.OffsetX > layer.MaxWidth ||
layer.Height + layer.OffsetY > layer.MaxHeight)
{
throw new InvalidOperationException("Layers must not extend beyond canvas borders");
}
for (int y = 0; y < layer.Height; y++)
{
for (int x = 0; x < layer.Width; x++)
{
Color previousColor = finalBitmap.GetPixel(x + layer.OffsetX, y + layer.OffsetY);
Color color = layer.GetPixel(x, y);
finalBitmap.SetPixel(x + layer.OffsetX, y + layer.OffsetY, BlendColor(previousColor, color, layerOpacity));
}
}
}
}
return(finalBitmap);
}
public override object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
{
if (values.Length > 0 && values[0] is Layer layer && ViewModelMain.Current?.BitmapManager?.ActiveDocument != null)
{
return((double)LayerStructureUtils.GetFinalLayerOpacity(layer, ViewModelMain.Current.BitmapManager.ActiveDocument.LayerStructure));
}
return(null);
}
