Hi I have been having a play with your route and am wondering if the lack of speed limits tags on part of Redbanks Road is part of the problem?
Also 60% for unpaved roads seems way too high, I would expect something more like walking pace unless you are driving a rally car. Phil (trigpoint) -- Sent from my Nokia N9 On 17/04/2013 8:07 Samuel Longiaru wrote: Hello Everyone, New to the list, having only discovered your project yesterday. Looks like a great effort. Congratulations. So being new, I'm a little reluctant to barge in. But I have been a long-term contributor to OSM and being recently transplanted from Canada to Australia, am curious about some rather bizarre routing that pops up on your demo website for this part of the world. So I started looking into it. http://osrm.at/2Vl shows a good example of what I'm talking about. While routing along the the M20 from Adelaide towards the Roseworthy Campus, the route leaves the M20 and continues on dirt roads. I think most would agree that continuing along the M20 to the next exit and following the paved Redbanks Road would be the more logical routing choice. This is only one example I've found of where dirt roads are suggested over much more logical choices. I've looked into the archives of this list as far back as I can go (only to January unfortunately) and didn't see these kinds of routing issues discussed. But I did find a feature request discussed in #389 and #497 on GitHub. In that discussion, there was a request for a default speed penalty of 0.6 for unpaved roads. From what I could gather, the issue was closed stating that while a penalty for bicycles might be appropriate, such a penalty was probably not appropriate for cars. In South Australia the default statutory speed limit on rural roads (paved or unpaved) is 100 kph, and some mappers have included the maxspeed=100 tag. That's correct... but crazy. I haven't checked, but some of those unpaved roads may in fact be "access=dry_weather" only, turning to red gumbo in the rainy season. Speed=0. I'm sure that in many places, the assumption that the travelling speed on unpaved roads is only 0.6 of the statutory limit is quite reasonable. If not that, then the "desirability factor" of driving on unpaved over paved may be 0.6. :) If my faint understanding of the project is correct, such speed rules can be set up in a customized LUA(?) and so may be resolvable. But I guess my point is, in the demo site, such adjustments should probably be made already. If the demo, set up for "Car (fastest)", routes off of M-roads and onto dirt, the routing engine has the "appearance" of not working correctly. I think the demo site should be adjusted to downgrade dirt roads at least, to better showcase the power and abilities of your project. The ultimate check of a routing engine is whether it gives results that are expected in a familiar area. In many cases around here, I'm left going "whuh?" Anyway, like I said, a fantastic effort. Something I definitely want to learn more about. Thanks, Samuel Longiaru Kamloops, BC... temporarily in South Australia _______________________________________________ OSRM-talk mailing list OSRM-talk@openstreetmap.org http://osrm.at/2Vl
_______________________________________________ OSRM-talk mailing list OSRM-talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/osrm-talk
