Being able to draw a control or to export this drawing e.g. to the clipboard is a major building block of every windows system. Unfortunately it is different on any of the otherwise similar xaml-platforms or not supported at all. E.g. to implement a charting library in WPF you would use a DrawingVisual to draw into its drawingcontext. The result can be exported as image if necessary. In Silverlight you eighter have to rely on heavy-weight shapes or use low-level, community-implemented drawing routines on WriteableBitmap which don't integrate with the rest of the UI (no Brushes, no Fonts, ...) The WinRt-Guys of Win8 really tell me, I have to use c++ with direct2d to just draw a simple window. Such think as this charting library or simple game could easily be portable would there be a portable and performant way to draw on all these xaml-based platforms.