Re: [OSM-talk] OSM maps of Denmark for download to Garmin devices
Splitter tries to automatically determine the maximum tile size for a specific area but the data in that area is giving Splitter false clues. This might be caused by e.g. a combination of many POI's but few roads. One way of working around those problem areas is to force Splitter to dimension the tiles so that they fewer nodes using the --max-nodes option. This is what I've done and now most of the world is rendered by Mkgmap without problems, except the ones in Denmark. Carsten Nielsen wrote: Very nice, but what is the reason for exactly those maps not beeing generated yet ? Carsten Nielsen Lambertus skrev: I plan to have those missing tiles for Denmark on http://garmin.na1400.info/routable.php fixed with the next update which is within a week. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] OSM maps of Denmark for download to Garmin devices
Lambertus wrote: Splitter tries to automatically determine the maximum tile size for a specific area but the data in that area is giving Splitter false clues. This might be caused by e.g. a combination of many POI's but few roads. 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. 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. Regards, Maarten ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] OSM maps of Denmark for download to Garmin devices
Lambertus wrote: Maarten Deen wrote: Lambertus wrote: Splitter tries to automatically determine the maximum tile size for a specific area but the data in that area is giving Splitter false clues. This might be caused by e.g. a combination of many POI's but few roads. 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 Nüvi and not a TomTom. 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. 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? Maarten inline: OSMmapsource.png___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] OSM maps of Denmark for download to Garmin devices
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 Nüvi 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
Re: [OSM-talk] OSM maps of Denmark for download to Garmin devices
On Wed, Apr 29, 2009 at 5:31 AM, Lambertus o...@na1400.info wrote: 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 Nüvi 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.listhttp://planetosm.oxilion.nl/%7Elambertus/america.list - http://planetosm.oxilion.nl/~lambertus/eurasia.listhttp://planetosm.oxilion.nl/%7Elambertus/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. Probably the reason for the overlap is nodes shared on a polyline which crosses a tile boundary, to prevent gaps. These shared nodes would extend the boundaries of each tile somewhat into the space of the neighboring tile. Otherwise, each tile would have to have a node exactly on the border, and the map resolution might not allow that. Shared nodes are required in routable maps (the shared nodes are marked as external to allow routing across tiles). Another reason I just thought of, which may explain why the overlap looks so large (larger than could be explained by shared nodes) is possibly the map projection used by MapSource. The projection might distort the map boundaries from a rectangle into something warped, but for simplicity MapSource only draws a straight line (not great circle) between the map boundary segments. Karl ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] OSM maps of Denmark for download to Garmin devices
Carsten Nielsen list_reply at toensberg.dk writes: Why is there nolonger any OSM based Garmin maps (img), available for download ? Have you tried http://downloads.cloudmade.com/europe/denmark/denmark.img.zip? -- Ed Avis e...@waniasset.com ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] OSM maps of Denmark for download to Garmin devices
I plan to have those missing tiles for Denmark on http://garmin.na1400.info/routable.php fixed with the next update which is within a week. Carsten Nielsen wrote: Why is there nolonger any OSM based Garmin maps (img), available for download ? I am just wondering why all the usual places for download of maps nolonger are providing files for Denmark ? http://www.osm4you.com/Europe/Denmark/denmark_gmapsupp_img.zip Only 330 bytes and useless file http://garmin.na1400.info/routable.php As the only place in europa no files area vailable for Denmark http://emexes.powweb.com/osm/ Is totally gone This is not a big problem for me because I can create my own maps with mkgmap, but it made wonder about som problems I have had. I have made my own garmin map files for some time (I want a bit more than just denmark) without problems, but after someone made a major import of public address information I was unable to create maps with mkgmap (even when using the splitter). I have made a little program that remove all the address nodes from my downloaded osm files, and now I can create garmin maps again. Is it the same problem that hit me which tis causing problems at themap sites aswell ? Are there anybody else out there that can make garmin maps of denmark with mkgmap ? ablansinger / Carsten Nielsen ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
