Maarten Deen wrote: > Lambertus wrote: >> Maarten Deen wrote: >>> Not to diminish your work on that front, but I find the tilelayout on >>> your site very strange. Of course it is a work of the splitter, but I >>> would opt for a manual layout, guided by an initial automated process. >>> >> Please forgive me for relying on the automated Splitter layout >> mechanism as I have no intention to manually divide the world into 500 >> tiles (317 America + 182 Europe/Asia/Africa/Oceania currently). >> Optimizing the tiles would result in even more, so you'd be talking >> about e.g 750 tiles. > > I'm certainly not complaining about your work. It's the reason why I > bought a Garmin NĂ¼vi and not a TomTom. > See Garmin...this is why you need to publicize your map format :-)
>> Needless to say: patches welcome ofcourse. The definition files for >> Splitter are: >> - http://planetosm.oxilion.nl/~lambertus/america.list >> - http://planetosm.oxilion.nl/~lambertus/eurasia.list >> >>> IMHO the strategy that the Mapsource tiles use is much more logical. >>> Take one big tile, if that has too many nodes, split it in half >>> horizontally, if that has too many nodes split it in half >>> vertically... repeat until you have a sufficient small amount of nodes. >>> >> This strategy is afaik exactly what Splitter does. > > Then it does it in a strange way. I'm sure you've noticed that the edges > of the tiles don't line up by just a few 1/100th of a degree in a lot of > places. That is inconsistent with a strategy of dividing a tile in half > if it has too many nodes. > E.g. tiles 63240113 and 63240116. One has a north border of 51.679688, > the other 51.635742. And then two tiles further east, 63240120 has a > north border of 52.679688 again. > Well, maybe not exactly in half, but the idea is the same. Afaik, the reason why Splitter doesn't split exactly in half is that there is less chance that a polygon is present in too many tiles. > BTW: have you seen that Mapsource draws the maps as overlapping? I've > attached a screenshot of how Mapsource displays maps 63240105 (yellow), > 63240175 (blue, continuing to the top) and 63240179 (green). > They all overlap eachother. According to their definitions, they should > not overlap, but mapsource apparently disagrees. > Any idea why that is? > I've seen this with topo maps made with older versions of Mkgmap as well. This might be a bug in Mkgmap or a misunderstanding of the Garmin map format but I don't think it's harmful though. _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk