On 2015-07-31 09:22, Martin Koppenhoefer wrote:
sent from a phone
Am 31.07.2015 um 07:41 schrieb Maarten Deen <md...@xs4all.nl>:
It is more than sufficient for a time calculation to use the maximum
speed, multiplied by some factor (smaller than 1), or even a fixed
speed per road class.
Sometimes it also depends on the region and the intensity of usage of
the road network. In certain metropolitan areas with at times more
traffic than the network can digest, you would be far off with this
metric. In these cases the general hierarchy of primary, secondary etc
becomes meaningless and often the best you can do is use small
lateral, residential roads to avoid the major traffic jam on the
arterial roads ;-)
That is why my next comment was:
Much better is virtually impossible to achieve since you don't know
how much traffic there is on the road so you can not predict waiting
times at traffic lights or junctions.
Most major routing systems use indeed real time traffic information
today, collected by other users of their system and by cellphone
networks
But for that you need some kind of online connection. And my tablet has
only wifi.
So that may be practical to use in some cases (phones with a dataplan),
you still need a general calculation which is not based on real time
traffic info. And for that you can only use general terms with respect
to speed and have to accept that the calculation will not be correct all
the time.
On top of this: I am not aware that OSMAND has this functionality ATM.
So talking about this is only hypothetical at the moment. It will not
result in better calculation times.
Maarten
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