Spotfire Ideas Portal
Today one can make one existing visualization a detail of another by going to the data properties and setting it to display data only from the marking of the parent. This works well but is a bit hidden.
There is another method that is also a bit too technical - if the user has set the legend to show the data limiting, which is not the default, one can change the data limiting as above but without going to the properties dialog.
It would be more "immersive" if one could somehow "drag" a chart, or perhaps some new visual indicator on a chart to another in order to restrict the data exactly as above.