How the engine runs your show
Arming, the story clock and the start gate: the execution model behind Helmo Rundown.
Your rundown is not executed by your browser. It is executed by Helmo Live's engine, which holds the whole show in memory and tells the output screens what to put on air and when.
When the engine gets your show
At Mark ready. That is what "arming" means: the engine loads the entire rundown (segments, stories, elements, clips, field changes) and publishes the list of media so the screens can start downloading it.
Go Live then starts the run. Arming and starting are two separate gestures on purpose: the gap between them is the standby window your media downloads in.
Segments and stories run in order
The engine works down the rundown in the order you built it: segment by segment, story by story. A Break takes its turn like everything else.
Elements run on the story's clock
Inside a story, elements are not a queue. They are placed in parallel against the story's clock: an element set to "at 00:05" goes on air five seconds after its story starts, whatever sits above it in the list.
This is why the list order is presentation, not timing, with one exception. An element set to With previous or After previous takes its time from the row above it, so moving that row moves the air. The rundown warns you on those rows.
What happens for each element
- It goes on air at its start.
- Any clips and field changes you scheduled play inside it while it holds.
- It comes off air at its end, either after its own duration, or with the story if it is set to hold.
Elements that have nothing to take off air (OBS, vMix, CasparCG, MeldStudio, streaming actions) fire once and are done. There is no OUT to send.
The start gate
At the top of a block the engine waits briefly for the screen to actually show the first video, so picture and clock start together. It waits up to 5 seconds when the clip is already downloaded, and up to 30 when a screen reports it is not.
What you can count on
- Predictable: segments and stories always play in the order you built them.
- Pause is clean: pausing holds everything, including field changes waiting to fire.
- Skip is clean: skipping takes the current graphic off and jumps to the right spot.
- It does not need you: the show runs on the server whether or not your browser is open.
The engine has the rundown as it was when you armed it. If you edit an on-air rundown, press Push changes to active rundown. The engine re-reads it and reconciles from the next story on, leaving whatever is on air alone.