Away from live, a launch shows from its lift-off on: its marker, label,
paths and orbit stay hidden while the world time is before it, so scrubbing
or playing brings the launches up in the order they flew. The selected
mission stays whenever it flies, and live shows every launch as before.
Play on the timeline runs the whole track in about a minute, from its start
when at live, and runs the clock itself past weather's own replay. It goes
live when it reaches now, or holds at an end that lies ahead of now. Going
live puts the rate back to 1.
The timeline shows whenever a layer with time to show is on, live or not.
Its track runs over the time those layers cover, reaching to now, with a
tick for each launch or frame and a handle to drag; arrows step between the
ticks, and a scrub to now goes live. The bar sits along the bottom of the
screen, and the dock and everything anchored above it rise by its height;
clean view, recording and the cockpit put it away with the dock.
The bar now needs more than the world clock being away from live: a layer
that moves with the clock must be on with time to show. In Core that is
weather radar, satellite or lightning with frames; a host adds layers by
following them. Turning the last one off hides the bar; turning it back
on brings it back.
The world clock reports this as `supported` in its state. Weather products
register their frames as coverage one by one, suspended or not, so the way
back to live stays on screen with reduced motion. Weather refreshes and
satellite catalog changes tell the clock their coverage may have changed.
A coverage that throws counts as none, and the clock reads its state once
per notification round.
A bar above the command dock, like a video player's: play and pause on
the left, the world time's date and time in UTC beside it, and Live to
return. It stays hidden while live, so Core looks as before until weather
history is scrubbed or replayed, a host moves the clock, or a link made
away from live is opened. Adds the pause and play_arrow glyphs and the
strings in every catalog.
Sameh Khamis