Changeset 32759 in osm for applications/viewer/jmapviewer

Timestamp:

2016-08-02T22:18:57+02:00 (9 years ago)

Author:

glebius

Message:

Restore proper operation of ScanexTileSource, broken by donvip somewhere
around r31573. The revision made ScanexTileSource equal to TMSTileSource,
not overriding anything, while overriding Y to Latitude calculation and
vice versa is crucial in this layer.

My fix has two remarkable notes:

• The internal private methods of ScanexTileSource don't use getTileSize(). The size of 256 (2^{8) is hardcoded in to the formulae, and right now I'm too lazy and stupid to get back to understanding them and rewriting them in a pretty way, so that 2}8 isn't hardcoded in there.
• latLonToXY() and xyToLatLon() are implemented, but I don't see any real usage of them. They aren't tested. Are they important at all?

File:

• applications/viewer/jmapviewer/src/org/openstreetmap/gui/jmapviewer/tilesources/ScanexTileSource.java (modified) (3 diffs)

applications/viewer/jmapviewer/src/org/openstreetmap/gui/jmapviewer/tilesources/ScanexTileSource.java

@@ -2 +2 @@
 package org.openstreetmap.gui.jmapviewer.tilesources;
 
+import java.awt.Point;
 import java.util.Random;
 
+import org.openstreetmap.gui.jmapviewer.Coordinate;
 import org.openstreetmap.gui.jmapviewer.OsmMercator;
+import org.openstreetmap.gui.jmapviewer.TileXY;
+import org.openstreetmap.gui.jmapviewer.interfaces.ICoordinate;
 
 /**
@@ -21 +25 @@
     private static final int DEFAULT_MAXZOOM = 14;
     private static final String API_KEY = "4018C5A9AECAD8868ED5DEB2E41D09F7";
-
-    // Latitude to Y and back calculations.
-
-    /** eccentricity of Earth's ellipsoid */
-    private static double E = 0.0818191908426;
 
     private enum ScanexLayer {
@@ -89 +88 @@
     }
 
+    // Latitude to Y and back calculations.
+    private static double RADIUS_E = 6378137;   /* radius of Earth at equator, 
+m */
+    private static double EQUATOR = 40075016.68557849; /* equator length, m */
+    private static double E = 0.0818191908426;  /* eccentricity of Earth's ellipsoid */
+
+    @Override
+    public Point latLonToXY(double lat, double lon, int zoom) {
+        return new Point(
+                (int) osmMercator.lonToX(lon, zoom),
+                (int) latToTileY(lat, zoom)
+                );
+    }
+
+    @Override
+    public ICoordinate xyToLatLon(int x, int y, int zoom) {
+        return new Coordinate(
+                tileYToLat((double) y, zoom),
+                osmMercator.xToLon(x, zoom)
+                );
+    }
+
+    @Override
+    public TileXY latLonToTileXY(double lat, double lon, int zoom) {
+        return new TileXY(
+                osmMercator.lonToX(lon, zoom) / getTileSize(),
+                latToTileY(lat, zoom)
+                );
+    }
+
+    @Override
+    public ICoordinate tileXYToLatLon(int x, int y, int zoom) {
+        return new Coordinate(
+                tileYToLat((double) y, zoom),
+                osmMercator.xToLon(x * getTileSize(), zoom)
+                );
+    }
+
+    private double latToTileY(double lat, int zoom) {
+        double tmp = Math.tan(Math.PI/4 * (1 + lat/90));
+        double pow = Math.pow(Math.tan(Math.PI/4 + Math.asin(E * Math.sin(Math.toRadians(lat)))/2), E);
+
+        return (EQUATOR/2 - (RADIUS_E * Math.log(tmp/pow))) * Math.pow(2.0, zoom) / EQUATOR;
+    }
+
     /*
      * To solve inverse formula latitude = f(y) we use