Events into and out of a protocol composition’s published ports
Changed in Vuo 2.0You no longer need to block unnecessary published input events with Allow Changes nodes.
Whether you’re running a protocol-compliant composition while exporting a movie, within an exported product such as a screensaver, or inside of another application, the same basic rules apply for how data and events enter through the published input ports:
A data-and-event published input port transmits its data and event whenever the data changes.
The first event enters through every published input port.
Subsequent events enter only through published input ports whose data has changed, generally speaking.
However, there are some exceptions. Depending on which data type the port has and who is running the composition (for example, Vuo or another application), the published input port may transmit every event.
An event-only published input port never transmits an event.
The next event comes in through the published input ports only after the composition has finished processing the current event and any events spun off from it.
Events spun off are those output by Spin Off Event, Spin Off Events, Spin Off Value, Build List, and Process List.
The composition has finished processing an event when the event either has reached the published output ports or has been blocked within the composition.
Changed in Vuo 2.0You no longer need to ensure that exactly one event reaches the published output ports for each event from the published input ports.
Image Generator, Image Filter, and Image Transition compositions are typically expected to do their jobs at a steady rate — receiving events and providing output images at evenly spaced time intervals. Triggers within a composition may fire additional events, but those events don’t affect the host (movie exporter, exported product, or other application) running the composition. The composition continues to provide output images at the same rate that it receives events.