On Sat, Jul 17, 2010 at 10:52 PM, Alan Millar <[email protected]> wrote:
> Am I really asking something unreasonable of a router that when an > xxxx_link way meets an xxxx way at a very low angle, the router should > know to go forward and not almost reverse? > I don't know. It sounds like a reasonable rule, but 1) is it necessarily *illegal* to make these turns, or is it just generally discouraged? and 2) Is it always the case? Marcus says that "such intersections with very sharp angles exist in many cities and are valid". He didn't make it clear whether these are instances of xxxx_link meeting xxxx (as opposed to xxxx meeting xxxx or yyyy), but if so, I'd like to see examples, and I suppose that kills this solution. I think if you want this enacted the first step would be to go through the database and provide a list of all the situations where it happens. Then we can go through, take a random sample, and get an idea of how often this type of turn is legal or illegal. We also can get an answer as to how widespread it is. If the numbers are low, we should just fix them by hand. If it's high, then maybe a different solution is going to have to be made. I just found one near where I live ( http://www.openstreetmap.org/?lat=28.077361&lon=-82.570335&zoom=18&layers=B000FTFany route from Alloway Street to/via Ehrlich Road). And if you look at the aerial, it's definitely not a dual carriageway. I'm not 100% sure whether or not it's a legal turn, though. I suspect it might be legal, *if* it can be done safely and without blocking traffic (i.e. when traffic is low). In which case, what is a router even supposed to do?
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