An roSGNode object sends roSGNodeEvent messages to a specified port when changes occur in nodes.  An roSGNodeEvent is also sent as the argument of field observer callback functions.  Both of these cases allow a SceneGraph application to respond to events.  roSGNodeEvent supports the following methods.


Retrieves the new field value at the time of the change.


Retrieves the name of the field that changed.


Retrieves the ID of the node that changed.


Retrieves a pointer to the node. This can be used for nodes without an ID.