Choose Between Pan and Scroll, or Direct Manipulation (Compact 2013)
3/26/2014
Whether you should use pan and scroll gestures, or direct manipulation gestures, depends on your touch panel hardware and how you use the gesture information in your application.
For a symmetric multi-touch panel, pan and scroll information is sufficient. When there are two touch points, pan and scroll messages provide the midpoint of the touch points and the distance between them, which is as much as can be known about touch points on a symmetric multi-touch panel. This is sufficient information for handling pan, scroll, pinch (zoom in) and spread (zoom out) gestures.
For a true multi-touch panel, only the direct manipulation gesture generates messages that have exact location information for two points. If the application needs this information (to implement rotate gestures, for example), then it must request direct manipulation gestures.