----- James Ewen <ve6...@gmail.com> wrote: > On Mon, Apr 22, 2013 at 3:33 PM, Samuel Longiaru <longi...@shaw.ca> wrote: > > > It seems to me that the OSRM routing could benefit greatly by a 0.6 penalty > > for > > unpaved roads as had been suggested a few time before, but they don't seem > > to > > want to go that way. > > Why incur a penalty just because the roadway is unpaved? A better > solution would be to have the ability to request paved roads only when > routing. That way the user could decide whether an unpaved roadway > should be selected or not. I suppose the best solution would be to > allow the user to select whether unpaved roads can be used for > routing, and also allow the user to select the "penalty" to apply for > unpaved. > > I fight with my GPS all the time. I tell it to never use unpaved > roads, but it will put me onto them quite often. Then on the other > hand it can try and send me on long detours some times when I know I > want to take that 2 mile shortcut on gravel to save 40 miles on > pavement. > > It's pretty tough to teach a computer to be as wishy-washy as a human! > > -- > James > VE6SRV > > _______________________________________________ > Talk-ca mailing list > Talk-ca@openstreetmap.org > http://lists.openstreetmap.org/listinfo/talk-ca
Paved roads only option? Yes, that's one way. Essentially giving unpaved roads a penalty value (factor) of 0. Then unpaved roads wouldn't be routed on. But consider the case where you are on an unpaved road and wish to route somewhere using the 'avoid unpaved roads' option. It would seem to me that in that case, the engine will need to assess a reasonable penalty for unpaved roads and minimize that penalty by getting you to paved roads by the quickest or shortest means. So either way you stack it, at some point, you need to assign a penalty. Right now, on the OSRM site, you can neither assign a penalty nor elect a paved-roads only option. All roads are reated equally. The yournavigation site must be doing something different, as it yields different (and more logical) results. I'd love to see a routing engine with a "desireability factor" that could be adjustable. If you really loathe unpaved roads, you could set the unpaved roads desirability factor low (i.e., apply a greater penalty for unpaved roads). And if you don't really care all that much whether you take paved or unpaved, then set the factor high. If your GPS had that, then maybe you wouldn't be fighting with it so much. :) Sam _______________________________________________ Talk-ca mailing list Talk-ca@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-ca
