X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=blobdiff_plain;f=altoslib%2FAltosMapTransform.java;h=b8901127366a7dc38930e9f173bd00c64bbd7cc0;hp=30994ecb60bc2dc826f50f6fffbc546b07882e24;hb=f078235803a80403014b3e54039fd2d0e0704367;hpb=3882e358b6f2970cb1afebcf2a71da34a57002df

diff --git a/altoslib/AltosMapTransform.java b/altoslib/AltosMapTransform.java
index 30994ecb..b8901127 100644
--- a/altoslib/AltosMapTransform.java
+++ b/altoslib/AltosMapTransform.java
@@ -15,7 +15,7 @@
  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  */
 
-package org.altusmetrum.altoslib_7;
+package org.altusmetrum.altoslib_10;
 
 import java.io.*;
 import java.lang.Math;
@@ -51,6 +51,13 @@ public class AltosMapTransform {
 		return new AltosPointDouble(screen.x + offset_x, screen.y + offset_y);
 	}
 
+	public double hypot(AltosLatLon a, AltosLatLon b) {
+		AltosPointDouble	a_pt = point(a);
+		AltosPointDouble	b_pt = point(b);
+
+		return Math.hypot(a_pt.x - b_pt.x, a_pt.y - b_pt.y);
+	}
+
 	public AltosLatLon screen_lat_lon(AltosPointInt screen) {
 		return lat_lon(screen_point(screen));
 	}
@@ -110,4 +117,12 @@ public class AltosMapTransform {
 		offset_x = centre_pt.x - width / 2.0;
 		offset_y = centre_pt.y - height / 2.0;
 	}
+
+	public static double lon_from_distance(double lat, double distance) {
+		double c = AltosGreatCircle.earth_radius * Math.cos(lat * Math.PI / 180) * 2 * Math.PI;
+
+		if (c < 10)
+			return 0;
+		return distance/c * 360.0;
+	}
 }