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skyebook/gist:3152659

Created July 20, 2012 19:13
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Mercator Meters Per Pixel
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gistfile1.java
public static final double EARTH_CIRCUMFERENCE = 637279.82;
public double getMetersPerPixelAt(LatLon latLon, int zoomLevel){
//S=C*cos(y)/2^(z+8)
double latCos = Math.cos(Math.toDegrees(latLon.getLat()));
System.out.println("latCos " + latCos);
double result = EARTH_CIRCUMFERENCE*latCos;
return result/Math.pow(2, zoomLevel+8);
}
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This has a bug where the result is always negative

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Converting the latitude from radians to degrees first fixes this

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Nope, this isn't fixed... still a bug </3

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