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This is more fun than a serious question, but I'd like to know if it's possible to display an OpenLayers map upside-down as per the uncommon, but interesting upside-down maps.

I guess it's mostly a matter of finding a source of the tiles and turning them 180 degrees, but I figure it's something someone has already thought through. I'm not the only one who's interested in the stories that are (or are not) being told through maps.

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    Like it. You could test it with vector data and a custom map projection (WGS84 rotated 180) maybe?
    – om_henners
    Commented Apr 13, 2012 at 3:42
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    How would you rotate a the tiles 180 degrees? Commented Apr 13, 2012 at 12:06
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    rotating the tiles won't give you what you're looking for. You'll have to rotate the original image the tiles where generated from then regenerate the tiles from that rotated image.
    – CaptDragon
    Commented Apr 13, 2012 at 12:43

1 Answer 1

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If you choose to store your data in PosGIS 2.0 you could make use of the new ST_FlipCoordinates function.

Example code snippet for a linestring:

SELECT ST_ASText( ST_FlipCoordinates(geom) ) as geom_flipped 
FROM ST_GeomFromText('LINESTRING(762091  2920414,762588 2920692,762676 2920779)‘,26986)  As geom;


--- geom_flipped -- 
LINESTRING(2920414 762091,2920692 762588,2920779  762676)

Thinking in polygons it would look somehow like that:

enter image description here

(Code and image source: PostGIS 2.0 the new stuff presentation by Regina Obe and Leo Hsu)

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  • That's neat, but is the step beyond what I was looking for. I'm curious about the tiles to start with. Commented Apr 13, 2012 at 11:58

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