[OSM-dev] projection for calculating distances in PostGIS

John Smith deltafoxtrot256 at gmail.com
Wed May 19 22:04:32 BST 2010


to make an area you would do something like this.

mid point = S25, E45
radius = 5km

>From there you can easily approximate small bounding box by doing
something like this:

top lat = midpoint - (radius / 100)
left lon = midpoint - (radius / 100)
bottom lat = midpoint + (radius / 100)
right lon = midpoint + (radius / 100)




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