public override HistoryMemento OnExecute(IHistoryWorkspace historyWorkspace)
{
if (historyWorkspace.Selection.IsEmpty)
{
return(null);
}
else
{
PdnRegion selectionRegion = historyWorkspace.Selection.CreateRegion();
if (selectionRegion.GetArea() == 0)
{
selectionRegion.Dispose();
return(null);
}
SelectionHistoryMemento sha = new SelectionHistoryMemento(StaticName, null, historyWorkspace);
ReplaceDocumentHistoryMemento rdha = new ReplaceDocumentHistoryMemento(StaticName, null, historyWorkspace);
Rectangle boundingBox;
Rectangle[] inverseRegionRects = null;
boundingBox = Utility.GetRegionBounds(selectionRegion);
using (PdnRegion inverseRegion = new PdnRegion(boundingBox))
{
inverseRegion.Exclude(selectionRegion);
inverseRegionRects = Utility.TranslateRectangles(
inverseRegion.GetRegionScansReadOnlyInt(),
-boundingBox.X,
-boundingBox.Y);
}
selectionRegion.Dispose();
selectionRegion = null;
Document oldDocument = historyWorkspace.Document; // TODO: serialize this to disk so we don't *have* to store the full thing
Document newDocument = new Document(boundingBox.Width, boundingBox.Height);
// copy the document's meta data over
newDocument.ReplaceMetaDataFrom(oldDocument);
foreach (Layer layer in oldDocument.Layers)
{
if (layer is BitmapLayer)
{
BitmapLayer oldLayer = (BitmapLayer)layer;
Surface croppedSurface = oldLayer.Surface.CreateWindow(boundingBox);
BitmapLayer newLayer = new BitmapLayer(croppedSurface);
ColorBgra clearWhite = ColorBgra.White.NewAlpha(0);
foreach (Rectangle rect in inverseRegionRects)
{
newLayer.Surface.Clear(rect, clearWhite);
}
newLayer.LoadProperties(oldLayer.SaveProperties());
newDocument.Layers.Add(newLayer);
}
else
{
throw new InvalidOperationException("Crop does not support Layers that are not BitmapLayers");
}
}
CompoundHistoryMemento cha = new CompoundHistoryMemento(
StaticName,
PdnResources.GetImageResource("Icons.MenuImageCropIcon.png"),
new HistoryMemento[] { sha, rdha });
EnterCriticalRegion();
historyWorkspace.Document = newDocument;
return(cha);
}
}