private DiagramDocumentCore PasteAndSelect(Stream buf, VectorT offset)
{
var doc = DeserializeAndEliminateDuplicateStyles(buf);
foreach (var shape in doc.Shapes)
{
shape.MoveBy(offset);
}
_doc.MergeShapes(doc);
_selectedShapes.Clear();
_selectedShapes.AddRange(doc.Shapes);
return(doc);
}