Controlling Events

The state of a surface is modified according to events received by the cluster mechanism. The following events are relevant:

Event	Meaning
Creation	This event is issued when a surface is instantiated.
SAS	This event marks the beginning of the acquisition sequence.
EAP	This event marks the end of any acquisition phases.
Exit Callback	This event is generated when the channel-proprietary callback function returns.
Cluster Ready	The state of the cluster determines the surface state transition towards PROCESSING.
Software Action	This kind of event corresponds to a deliberate user action on the SurfaceState parameter.