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Cambrian series 2B

Cambrian audax series 2B, Chepstow start & anticlockwise.  See:

https://crazyenglishtriathlete.wordpress.com/2015/12/26/cambrian-series-permanents/

http://www.aukweb.net/perms/detail/CB18/

Thank you

I'm quick enough to speak when I see something wrong so let me balance that a bit by saying thank you for the map update that is in progress.  I've not submitted a single map correction since October, I'll not be so lax this time.

Cheers Richard

DFWW

Dr Foster's Winter Warmer 200k audax

GPS vs saved route oddness - cacheing issue

Hi Richard,

This one might be difficult to explain and I've no idea if anything can be done about it or even if it's a real problem.

First create a route and save it.  Next change the route slightly and save it again with the same name.  Close the route and open it again.  At this point I am seeing the original route not the revised one.  This I understand, it's simply a browser cache issue.  If I shift+F5 the page is refreshed from your server and I now see the revised route.

Back up a stage to the point where the route has been revised, saved, closed and reopened but the browser has not been refreshed.  If I ask for a GPS file at that point which route would you expect me to get?  I expected the GPS file to match the saved revised route but it does not, I get a GPS file for the original route.  My expectation of getting the revised route was because the GPS file isn't cached, this is my first request for it so it has to be coming from your server not my cache.

The only explanation I can think of relates to you mentioning in discussions about waypoint limits that the waypoints and hence the route are embedded in the URL my browser requests.  When I request a GPS file does the browser send over 'give me the GPS file for a route from A to F with waypoints BCD and E'? This would be the route I am seeing and could be out of date due to browser cacheing.  Or does my browser say 'give me the GPS file for route number 12345678'?  That should always return the saved route.

I was expecting the latter behaviour and that was because I (wrongly) thought you have to save a route to get the GPS of it just as you have to save before you can print maps to pdf.  In writing this and checking my facts I find I am wrong in believing I must save to get a GPS file.

So now I've realised the mistake is mine why am I not cancelling my post?  If I create a route in the manner described above and download maps, GPS file and turn by turn instructions will all three match?  I think they might not.  The GPS comes from my cached URL I now believe.  The route has to be saved to create maps so logically the maps are created from the saved route, this would lead to the map not matching the GPS in my scenario.  Printing turn by turn does not prompt to save the route so I would expect that to match the GPS.

Am I making any sense at all?

Julian

Double chevrons = one way streets?

I think they must be?

Some are showing the wrong direction, eg Church Road and Lower Church Street in Chepstow.  These are 18954933 and 18954931 in OSM.  The OSM map shows the arrows in the correct direction and C.T uses the roads in the correct direction.  It's just the chevrons that are drawn the wrong way round. 

At a guess it is because for those roads the OneWay tag is -1, other nearby one way roads that get marked correctly have OneWay=yes.  It seems oneway=yes is used when the road was drawn in the direction of traffic flow and -1 is used when the node list of the way is opposite to traffic flow.  Seems the routing understands both OneWay tag variants but the chevrons are drawn according to the direction of the node list.

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