[OSM-talk] Wrong scale in slippy map
pchilds at bcs.org
Fri Apr 24 10:31:39 BST 2009
2009/4/24 Juan Lucas Dominguez Rubio <jldominguez at prodevelop.es>:
> At the deep zoom levels (zoom=6 and higher numbers), Sweden and
> Finland don't look "large", because you don't see other countries
> on the same screen. At these deep zoom levels, the difference in
> scale between the top and bottom of the screen is also small.
They don't look large, but they do looked stretched, ie the wrong
shape. 100 Pixels East West is NOT the same distance as 100 pixels
North South. It also makes the scale pointless as you need one for
North-South and a different for East-West.
I think we ought to be able to do a projection where we turn the globe
into a symmetrical regular polyhedra. In effect at zoom level zoom
level 1 the world is a tetrahedron, as you go up you add more
equilateral triangles. while keeping your angles the same.
At each higher zoom level each triangular faces is split into 3
triangles. creating what gets closer and closer to a globe. Same way
as some footballs are made up of hexagons......
Just a thought.
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