geodesic

Creating a Geodesic Circle in OpenLayers

I recently asked a question on GIS Stack Exchange on how to create a  buffer around a point that took into account the curvature of the earth. OpenLayers has support for geodesic measurements, but not creating geodesic polygons. Drawing a standard polygon on a Mercator projected map can produce features with very different measurements from […]



Watch out for OpenLayer Distances

I had the fortune on my most recent project, a MapFish mapping system, of having someone else do some thorough testing. One thing that had escaped me, was both the measure tool and area tool were returning incorrect results. The distance as-the-crow flies between Dublin and Cork is 219 kilometres (136.08 miles in old money) […]