On Sun, Mar 6, 2011 at 5:20 AM, Stewart C. Russell <scr...@gmail.com> wrote:
> If it's any consolation, Garmin's maps will suggest u-turns in the > middle of highways too. Every time I want to go to Point Edward, the > Garmin tells me to pull a U-ey in the middle of the 402. That's not a u-turn... it's a sharp left! I think every routing engine figures that a u-turn can only take place on a non-divided highway. As soon as you have a dual carriageway, then "rippin' a 180" is fair game. Even so, where that dual carriage way ends and forms a Y with a single carriageway, my GPS navigator thinks that's a good place to spin around. Looking at it from a computer coding point of view, how do you determine when that little bit of road between the opposing lanes is no longer a cut in the median, but a street on it's own? To be fair, most humans these days can't figure out what a cut in the median is... There are so many idiots out there that think it is legal to pull across a set of lanes, and stop in the median waiting for a break in the traffic traveling in the opposite direction. Or even better boneheads that are signalling for a left hand turn while you are doing the same facing them that try to go around you to their right in the middle of the intersection before completing the left hand turn. Both of these maneuvers are not only dangerous, but completely illegal. I've taken to sitting at dual carriageway intersections waiting to make a left turn until there are no more oncoming vehicles facing me with left turn signals on. If I try to drive properly there's a good chance for a collision or at the very least a bunch of finger action from the bozo that is breaking the law. Even the "experts" who design the roadways aren't in the clear... we have a dual carriageway in Edmonton with a fairly wide median. The traffic planning experts put an extra set of lights in the middle of the intersection as well. When making a left hand turn, you have to stop for the set of lights to cross what used to be the oncoming lanes. There's room for about 2 passenger cars to make the turn on each change of lights. A large semi ends up blocking the intersection because the trailer hasn't cleared the roadway by the time the steering axle hits the stop line. Put two B-trains opposing each other and that intersection is done... I can't recall where that intersection was... I haven't been by it for years. Had a quick look at the map, but it's not coming to me. Maybe it has been removed and corrected now. The traffic planners have resorted to putting in long left hand turn lanes which put the opposing drivers to the left of the oncoming vehicles in an effort to keep people from attempting to interlock the vehicles while making left turns... http://www.openstreetmap.org/?lat=53.46537&lon=-113.466058&zoom=18&layers=M The days of the Uniform Traffic Act are long gone. James VE6SRV _______________________________________________ Talk-ca mailing list Talk-ca@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-ca