Manual / Overlays

Overlays

Four things the app can draw over the network: how the traffic is running, what the road authority says is shut, where buses have bunched or dropped a gap, and which structures are too low. Each is a separate source, each is switched on separately, and each measures something the others do not.

The pages here

Two things that are true of all four

Every overlay explains itself at the bottom of the map. Switching one on adds a block to the bar along the bottom centre carrying its key, how old what you are looking at is, and its own controls. If a colour on the map puzzles you, the answer is in that bar rather than in this manual.

None of them measures a bus. The traffic overlay measures roads, the incidents overlay reports what an authority published about roads, the clearance overlay measures structures, and the frequency overlay measures two buses against each other. The only thing on this map that measures one bus against its timetable is the bus dot itself (Live buses and what the colours mean). No colour on one of these scales can be compared with a colour on another, and the app never derives one from another.

And one that trips people up

An overlay that is missing is almost never broken. Each one needs a source, and where a deployment has not been given that source the app draws no tile for it rather than a switch that fails. If a tile described here is not in your Layers panel, the answer is to ask whoever runs this deployment — not to report a fault. Turning overlays on and off sets out how to tell the two apart.