Tom Hughes wrote: > Matthias Brandt wrote: >> Tom Hughes wrote: >>> Matthias Brandt wrote: >>> >>>> i've searched the archive of this mailinglist and the wiki about >>>> the magical y-boundary set to 85.05113° (respective 180° projected) >>>> in the Mercator Projection. >>> >>> Did you have an alternative value in mind? >> Not really. But I would like to know, if there is any reason for >> this. I'm writing my Bachelorthesis about OpenStreetMaps and I would >> like to explain this bound. > > If what you're asking is why it doesn't just go to 90 degrees then you > might want to consider what happens to the projection function in the > limit as the latitude approaches 90 degrees... Yes, I know the problem with values reaching 90°.
Iván Sánchez Ortega wrote: > Quadtiles, quadtiles, quadtiles. Having a big square allows you to > subdivide images in a fashion similar to quadtrees. Using rectangles would > mess things up. > Thank you! That's what I needed to know :-) Matthias _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
