Re: [OSM-talk] OSM maps of Denmark for download to Garmin devices

[Maarten Deen]

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
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