[Tagging] Traffic signal warning lights?

[Tom Pfeifer]

On 13.01.2022 09:36, Martin Koppenhoefer wrote:
>> On 13 Jan 2022, at 00:57, Graeme Fitzpatrick <graemefitz1 at gmail.com> wrote:
>> I'm thinking of highway=traffic_signals + traffic_signals=advance_warning.
> 
> 
> I agree that they aren’t traffic signals in the sense of the OpenStreetMap tag, that’s why they 
> shouldn’t get the highway=traffic_signals tag, regardless of additional tags.

Indeed highway=traffic_signals is unsuitable, since it breaks backward compatibility.

When a routing engine encounters highway=traffic_signals it calculates an average waiting time,
and so far it did not have to evaluate sub-tagging for that task.

Thus a different high-level value is needed for signals that create driver attention but do not 
influence driving time.

tom