SoEventCallback will invoke application supplied callback functions during
SoHandleEventAction traversal. Methods allow the application to specify which Inventor events should trigger callbacks, and which path must be picked, if any, for
the callback invocation to occur. The application callback is able to get information about the event and the pick detail, and may grab events, release events, and set whether the event was handled.
If
you register more than one callback function in an
SoEventCallback node, all the callback functions will be invoked when an event occurs, even if one of the callbacks handles the event. However, if the event is handled
by any of the callback functions, no other node in the scene graph will see the event.