> On Mon, 28 Dec 2009, Roy Wallace wrote: >> Also, incline=* is still mathematically valid for nodes to indicate >> the instantaneous incline at that point, so I don't see a problem with >> that. > > I might be old, I might have gone to school in the Dark Ages, but a point > cannot have an incline.
But the point is part of a way, and the way *does* have a gradient at that point, which is what Roy meant by "instantaneous incline at that point" (assuming that a road's altitude is differentiable, a fairly safe assumption). Most places I've ever seen where the road is very steep usually have a sign telling you how steep In the UK they look like this one I came across in Leek in Staffordshire (which I stupidly decided to cycle in both directions) http://www.flickr.com/photos/19863...@n00/4224573437/ In the UK, older signs are often found with the gradient expressed as a ratio e.g. 1:5 Might be worth using incline = 20%, (or if the way is reversed incline = -20%), instead of just steep if the information is available (i.e. as a sign). Presumably the gradient on the sign is the maximum gradient along the way in question, so might be some sense in marking the point where the gradient is a maximum as a node. Having said that, if you are driving a laden truck, or indeed cycling etc., you might be interested about knowing that a length of way was steep, rather than just that the gradient at a point further up is x%. You may be able to turn off before reaching the steep section of road, but you won't know where it starts unless someone uses a way to tag the incline. _______________________________________________ Tagging mailing list [email protected] http://lists.openstreetmap.org/listinfo/tagging
