[Gdal-dev] Projected vs Geographic Coordinate Systems

Simon Perkins sy at perkins.net
Tue Mar 20 00:43:31 EDT 2007

> Here I go responding out of order.

I'm just grateful anyone's responding at all at this time of the night!

> I just assume if folks are displaying things in a geographic coordinate
> system that they don't care about the distortion.  Likewise, if they
> display things in a projected coordinate system I don't try to analyse
> whether it is locally appropriate or not.   Projections are all distorted
> too after all, just presumably not in harmful ways locally.

So, just to clarify, if OpenEV is displaying a vector layer, it displays 
the coordinates isotropically? i.e. horizontal screen distances relate 
to longitude in the same ratio as vertical screen pixels relate to 
latitude? Is this pretty common practice in the GIS world?

I guess I've just been spoiled by playing with Google Earth too much... :)


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