Using the TriggerAnalyticsviaXML, I am able to send a trigger to the alarm panel and include an overlay that displays a polygon by specifying the points. I was wondering if it would be possible to do so through the metadata way. Looking through the examples, there only seems to be support for displaying bounding boxes even though the ONVIF format allows for a polygon with a point list.
The Smart Client supports metadata Bounding Boxes directly, so you do not have to develop anything to get metadata Bounding Boxes displayed in the Smart Client.
If you want to have the Smart Client display overlay based on other information in the metadata, it is possible, but it would require that you develop a Smart Client plugin that draws the overlay.
If you have developed a Smart Client plugin that is capable of doing an overlay polygon based on Analytic Events data, it should be possible (perhaps even easy) for you to do polygon overlay based on Metadata.
You can explore how to read metadata by seeing the Metadata Live Viewer (and Metadata Playback Viewer) sample.
I have not actually developed a plugin yet. The analytics Event is being triggered by the XML overlay. Is the plugin responsible for handling that the smart client overlay graph on event example? or does the XML trigger by a separate process?
You can use XML to trigger an analytics event. This is the TriggerAnalyticsviaXML sample.
You can have a plugin that display overlay based on events. This is the Smart Client Overlay Graph on Event plugin sample (or Smart Client Overlay on Event or Analytics Overlay).
You can submit metadata instead of analytics events. Bounding Box Metadata Provider sample.
You can read metadata. Metadata Live Viewer sample.
There is no plugin sample that display metadata overlay in the Smart Client. (Bounding Boxes are displayed without implementing a plugin.)
Analytics Events and Metadata are similar in some respects and different in others