001package org.openstreetmap.gui.jmapviewer.tilesources;
002
003import java.util.Random;
004
005import org.openstreetmap.gui.jmapviewer.OsmMercator;
006
007public class ScanexTileSource extends AbstractTMSTileSource {
008    private static String API_KEY = "4018C5A9AECAD8868ED5DEB2E41D09F7";
009
010    private enum ScanexLayer {
011        IRS("irs", "/TileSender.ashx?ModeKey=tile&MapName=F7B8CF651682420FA1749D894C8AD0F6&LayerName=BAC78D764F0443BD9AF93E7A998C9F5B"),
012        SPOT("spot", "/TileSender.ashx?ModeKey=tile&MapName=F7B8CF651682420FA1749D894C8AD0F6&LayerName=F51CE95441284AF6B2FC319B609C7DEC");
013
014        private String name;
015        private String uri;
016
017        ScanexLayer(String name, String uri) {
018            this.name = name;
019            this.uri = uri;
020        }
021        public String getName() {
022            return name;
023        }
024        public String getUri() {
025            return uri;
026        }
027    }
028
029    /* IRS by default */
030    private ScanexLayer Layer = ScanexLayer.IRS;
031
032    public ScanexTileSource(String url) {
033        super("Scanex " + url, "http://maps.kosmosnimki.ru");
034
035        for (ScanexLayer layer : ScanexLayer.values()) {
036            if (url.equalsIgnoreCase(layer.getName())) {
037                this.Layer = layer;
038                break;
039            }
040        }
041    }
042
043    @Override
044    public int getMaxZoom() {
045        return 14;
046    }
047
048    @Override
049    public String getExtension() {
050        return("jpeg");
051    }
052
053    @Override
054    public String getTilePath(int zoom, int tilex, int tiley) {
055        int tmp = (int)Math.pow(2.0, zoom - 1);
056
057        tilex = tilex - tmp;
058        tiley = tmp - tiley - 1;
059
060        return this.Layer.getUri() + "&apikey=" + API_KEY + "&x=" + tilex + "&y=" + tiley + "&z=" + zoom;
061    }
062
063    public TileUpdate getTileUpdate() {
064        return TileUpdate.IfNoneMatch;
065    }
066
067    private static double RADIUS_E = 6378137;   /* radius of Earth at equator, m */
068    private static double EQUATOR = 40075016.68557849; /* equator length, m */
069    private static double E = 0.0818191908426;  /* eccentricity of Earth's ellipsoid */
070
071    @Override
072    public double latToTileY(double lat, int zoom) {
073        double tmp = Math.tan(Math.PI/4 * (1 + lat/90));
074        double pow = Math.pow(Math.tan(Math.PI/4 + Math.asin(E * Math.sin(Math.toRadians(lat)))/2), E);
075
076        return (EQUATOR/2 - (RADIUS_E * Math.log(tmp/pow))) * Math.pow(2.0, zoom) / EQUATOR;
077    }
078
079    @Override
080    public double lonToTileX(double lon, int zoom) {
081        return (RADIUS_E * lon * Math.PI / (90*EQUATOR) + 1) * Math.pow(2.0, zoom - 1);
082    }
083
084    /*
085     * To solve inverse formula latitude = f(y) we use
086     * Newton's method. We cache previous calculated latitude,
087     * because new one is usually close to the old one. In case
088     * if solution gets out of bounds, we reset to a new random
089     * value.
090     */
091    private double cached_lat = 0;
092
093    @Override
094    public double tileYToLat(int y, int zoom) {
095    Random r= new Random();
096        double lat0, lat;
097
098    lat = cached_lat;
099    do {
100        lat0 = lat;
101            lat = lat - Math.toDegrees(NextTerm(Math.toRadians(lat), y, zoom));
102            if (lat > OsmMercator.MAX_LAT || lat < OsmMercator.MIN_LAT) {
103                lat = OsmMercator.MIN_LAT +
104                    (double )r.nextInt((int )(OsmMercator.MAX_LAT -
105                    OsmMercator.MIN_LAT));
106            }
107    } while ((Math.abs(lat0 - lat) > 0.000001));
108
109    cached_lat = lat;
110
111        return (lat);
112    }
113
114    /* Next term in Newton's polynomial */
115    private double NextTerm(double lat, double y, int zoom) {
116        double sinl=Math.sin(lat);
117        double cosl=Math.cos(lat);
118    double ec, f, df;
119
120        zoom = (int )Math.pow(2.0, zoom - 1);
121    ec = Math.exp((1 - y/zoom)*Math.PI);
122
123    f = (Math.tan(Math.PI/4+lat/2) -
124        ec * Math.pow(Math.tan(Math.PI/4 + Math.asin(E * sinl)/2), E));
125        df = 1/(1 - sinl) - ec * E * cosl/((1 - E * sinl) *
126            (Math.sqrt (1 - E * E * sinl * sinl)));
127
128        return (f/df);
129    }
130
131    @Override
132    public double tileXToLon(int x, int zoom) {
133        return (x / Math.pow(2.0, zoom - 1) - 1) * (90*EQUATOR) / RADIUS_E / Math.PI;
134    }
135}