When we were ready to consolidate our frameworks in the spring of ’04 we started hearing more about a GPU-accelerated UI framework called Avalon (now called Windows Presentation Framework or WPF.)  Since it was from the Windows group, we only expected a nicer User/GDI but we nonetheless did the due diligence and explored it.  Even in those early stages everyone was pretty amazed at the demos and what the API provided.  The “RenderTransform” on Avalon allowed you to rotate parts of your app to face arbitrary directions.  Another part of Avalon that encouraged us to use it was “RoutedEvents.”  This lets us send events from the Surface input hardware right to the appropriate application UI components.  It was almost as if they had Surface in mind even before anyone ever heard of Surface, said Kevin Kennedy.

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