X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=altoslib%2FAltosMapTransform.java;h=3f8f290c9f87faa419358de317a3210ea879d583;hb=3ed101d634968666cd3ee2d8c49737970caf406b;hp=266557b60b94ad96aaa43fe67529ac6f2b4a40e5;hpb=1085ec5d57e0ed5d132f2bbdac1a0b6a32c0ab4a;p=fw%2Faltos

diff --git a/altoslib/AltosMapTransform.java b/altoslib/AltosMapTransform.java
index 266557b6..3f8f290c 100644
--- a/altoslib/AltosMapTransform.java
+++ b/altoslib/AltosMapTransform.java
@@ -16,7 +16,7 @@
  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  */
 
-package org.altusmetrum.altoslib_11;
+package org.altusmetrum.altoslib_14;
 
 import java.io.*;
 import java.lang.Math;
@@ -29,6 +29,8 @@ public class AltosMapTransform {
 
 	double	offset_x, offset_y;
 
+	int	width, height;
+
 	public AltosLatLon lat_lon (AltosPointDouble point) {
 		double lat, lon;
 		double rads;
@@ -67,13 +69,13 @@ public class AltosMapTransform {
 		return lat_lon(screen_point(screen));
 	}
 
-	public AltosPointDouble point(AltosLatLon lat_lon) {
+	public  AltosPointDouble point(double lat, double lon) {
 		double x, y;
 		double e;
 
-		x = lat_lon.lon * scale_x;
+		x = lon * scale_x;
 
-		e = Math.sin(Math.toRadians(lat_lon.lat));
+		e = Math.sin(Math.toRadians(lat));
 		e = Math.max(e,-(1-1.0E-15));
 		e = Math.min(e,  1-1.0E-15 );
 
@@ -82,6 +84,10 @@ public class AltosMapTransform {
 		return new AltosPointDouble(x, y);
 	}
 
+	public AltosPointDouble point(AltosLatLon lat_lon) {
+		return point(lat_lon.lat, lat_lon.lon);
+	}
+
 	public AltosPointDouble screen(AltosPointDouble point) {
 		return new AltosPointDouble(point.x - offset_x, point.y - offset_y);
 	}
@@ -102,6 +108,43 @@ public class AltosMapTransform {
 		return screen(point(lat_lon));
 	}
 
+	public AltosPointDouble screen(double lat, double lon) {
+		return screen(point(lat, lon));
+	}
+
+	/* Return first longitude value which ends up on-screen */
+	public double first_lon(double lon) {
+		/* Find a longitude left of the screen */
+		for (;;) {
+			double x = lon * scale_x - offset_x;
+			if (x < 0)
+				break;
+			lon -= 360.0;
+		}
+		/* Find the first longitude on the screen */
+		for (;;) {
+			double x = lon * scale_x - offset_x;
+			if (x >= 0)
+				break;
+			lon += 360.0;
+		}
+		return lon;
+	}
+
+	/* Return last longitude value which ends up on-screen */
+	public double last_lon(double lon) {
+		lon = first_lon(lon);
+
+		for(;;) {
+			double next_lon = lon + 360.0;
+			double next_x = next_lon * scale_x - offset_x;
+			if (next_x >= width)
+				break;
+			lon = next_lon;
+		}
+		return lon;
+	}
+
 	private boolean has_location;
 
 	public boolean has_location() {
@@ -112,6 +155,9 @@ public class AltosMapTransform {
 		scale_x = 256/360.0 * Math.pow(2, zoom);
 		scale_y = 256/(2.0*Math.PI) * Math.pow(2, zoom);
 
+		this.width = width;
+		this.height = height;
+
 		AltosPointDouble centre_pt = point(centre_lat_lon);
 
 		has_location = (centre_lat_lon.lat != 0 || centre_lat_lon.lon != 0);