I revisited the custom tooltip implementation that I prepared to demonstrate the Revit 2013 API features including the View API and its UIView class. It class still provides the only possibility to convert back and forth between Revit model coordinates and Windows device screen points. That functionality can be combined with the ReferenceIntersector to shoot a ray through the model to determine what Revit database element is located under the current cursor position and display a custom tooltip presenting information about it or anything else you please...

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