1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
|
package tim.prune.data;
public abstract class Bearing
{
/**
* Calculate the initial bearing from one point to another
* @param inFromPoint starting point
* @param inToPoint finishing point
* @return initial angle in degrees clockwise from North
*/
public static double calculateDegrees(DataPoint inFromPoint, DataPoint inToPoint)
{
double deltaLong = Math.toRadians(inToPoint.getLongitude().getDouble()
- inFromPoint.getLongitude().getDouble());
double sinDeltaLong = Math.sin(deltaLong);
double cosDeltaLong = Math.cos(deltaLong);
double lat1 = Math.toRadians(inFromPoint.getLatitude().getDouble());
double lat2 = Math.toRadians(inToPoint.getLatitude().getDouble());
double angleRadians = Math.atan2(sinDeltaLong * Math.cos(lat2),
Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1) * Math.cos(lat2) * cosDeltaLong);
return Math.toDegrees(angleRadians);
}
public static double calculateDegreeChange(DataPoint inFromPoint, DataPoint inMidPoint, DataPoint inToPoint)
{
if (inFromPoint == null || inMidPoint == null || inToPoint == null) {
return 180.0; // cannot calculate
}
final double firstAngle = calculateDegrees(inFromPoint, inMidPoint);
final double secondAngle = calculateDegrees(inMidPoint, inToPoint);
return angleDifferenceDegrees(firstAngle, secondAngle);
}
public static double angleDifferenceDegrees(double inFirstDeg, double inSecondDeg)
{
double angleDiff = Math.abs(inFirstDeg - inSecondDeg) % 360.0;
return angleDiff > 180.0 ? (360.0 - angleDiff) : angleDiff;
}
}
|
