On Sun, 2010-05-02 at 22:37 +1000, Steve Bennett wrote: > On Fri, Apr 30, 2010 at 2:46 PM, David Murn <da...@incanberra.com.au> wrote: > > While I agree that its useful to represent curves and bends properly in > > the traffic flow, this seems a bit excessive. Youre going from having 9 > > roundabouts with 36 nodes, to having 9 roundabouts using 162 nodes, for > > no reason other than so it renders a little bit nicer? > > It's not just "rendering" - it also affects how it appears on a GPS. > Presumably more accurate circles mean more accurate distance > calculations, too.
The distance difference between a diamond and a circle is about the same as using the inside/outside lane, ie. unless you were looking at the distance over a road with a high number of round-abouts in a very short distance, I dont think youd really notice a couple of meters here or there. > > One question I do have though, is why put the roundabouts in, and not > > split up the entry/exit ways? > > Individual lanes mapped as separate ways considered harmful. Aussie tagging guidelines say (and Ive checked, no wikifiddling of this part for over 12 months): # Roundabouts should be drawn out in full, make the way go clockwise, # and the correct direction of movement is then shown on the map. Mark # it junction=roundabout # # Please read the following page as well. Tag:junction=roundabout # # Note: each entry and exit way should join the roundabout at a separate # node. Where is there discussion about the 'harmful' effect of tagging each entry/exit way? Ive had a quick look but only came across that comment. David _______________________________________________ Talk-au mailing list Talk-au@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-au
