[mkgmap-dev] how to convert Coord.distanceInDegreesSquared() to MapUnits?

Wed Jan 30 07:58:02 GMT 2013

GerdP wrote
> Hi,
> 
> what is the correct way to convert the value
> returned by Coord.distanceInDegreesSquared() into map units?
> 
> A simple code like this seems not to work:
> double distSq = co1.distanceInDegreesSquared(co2);
> int mapUnits = Utils.toMapUnit(Math.sqrt(distSq));
> 
> Gerd

OK, I learned that I have to know the latitude to do the calculation.
In splitter, this (simplified) formula is used to calculate the width of a
bbox:
  factor = Math.cos(Math.toRadians(Utils.toDegrees(lat))); 
  double width = (maxLon-minLon) * factor

Gerd

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