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package tim.prune.gui.map;
/**
* Class to manage coordinate conversions for maps
*/
public abstract class MapUtils
{
/**
* Transform a longitude into an x coordinate
* @param inLon longitude in degrees
* @return scaled X value from 0 to 1
*/
public static double getXFromLongitude(double inLon)
{
return (inLon + 180.0) / 360.0;
}
/**
* Transform a latitude into a y coordinate
* @param inLat latitude in degrees
* @return scaled Y value from 0 to 1
*/
public static double getYFromLatitude(double inLat)
{
return (1 - Math.log(Math.tan(inLat * Math.PI / 180) + 1 / Math.cos(inLat * Math.PI / 180)) / Math.PI) / 2;
}
/**
* Transform an x coordinate into a longitude
* @param inX scaled X value from 0 to 1
* @return longitude in degrees
*/
public static double getLongitudeFromX(double inX)
{
return inX * 360.0 - 180.0;
}
/**
* Transform a y coordinate into a latitude
* @param inY scaled Y value from 0 to 1
* @return latitude in degrees
*/
public static double getLatitudeFromY(double inY)
{
double n = Math.PI * (1 - 2 * inY);
return 180 / Math.PI * Math.atan(0.5 * (Math.exp(n) - Math.exp(-n)));
}
}
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