1.worldwindjava新增谷歌衛星圖層

/*
 * Copyright (C) 2017 United States Government as represented by the Administrator of the
 * National Aeronautics and Space Administration.
 * All Rights Reserved.
 */

package gov.nasa.worldwind.layers.Earth;
 
import java.net.MalformedURLException;
import java.net.URL;
 
import gov.nasa.worldwind.avlist.AVKey;
import gov.nasa.worldwind.avlist.AVList;
import gov.nasa.worldwind.avlist.AVListImpl;
import gov.nasa.worldwind.geom.Angle;
import gov.nasa.worldwind.geom.LatLon;
import gov.nasa.worldwind.layers.mercator.BasicMercatorTiledImageLayer;
import gov.nasa.worldwind.layers.mercator.MercatorSector;
import gov.nasa.worldwind.util.LevelSet;
import gov.nasa.worldwind.util.Tile;
import gov.nasa.worldwind.util.TileUrlBuilder;
 
public class GoogleLayer extends BasicMercatorTiledImageLayer{
 
    public GoogleLayer() {
        super(makeLevels());
        // TODO Auto-generated constructor stub
    }
 
    private static LevelSet makeLevels() {
        // TODO Auto-generated method stub
        AVList params = new AVListImpl();
 
        params.setValue(AVKey.TILE_WIDTH, 256);
        params.setValue(AVKey.TILE_HEIGHT, 256);
        params.setValue(AVKey.DATA_CACHE_NAME, "Earth/GoogleMap");
        params.setValue(AVKey.DATASET_NAME, "*");
        params.setValue(AVKey.FORMAT_SUFFIX, ".jpg");
        params.setValue(AVKey.NUM_LEVELS, 16);
        params.setValue(AVKey.NUM_EMPTY_LEVELS, 0);
        params.setValue(AVKey.LEVEL_ZERO_TILE_DELTA, new LatLon(Angle
                .fromDegrees(22.5d), Angle.fromDegrees(45d)));
        params.setValue(AVKey.SECTOR, new MercatorSector(-1.0, 1.0,
                Angle.NEG180, Angle.POS180));
        params.setValue(AVKey.TILE_URL_BUILDER, new URLBuilder());
 
        return new LevelSet(params);
    }
    private static class URLBuilder implements TileUrlBuilder
    {
        public URL getURL(Tile tile, String imageFormat)
                throws MalformedURLException
        {
            String url=String.format(
                    "http://www.google.cn/maps/
 
[email protected]&gl=cn&x=%s&y=%s&z=%s",
                    tile.getColumn(),
                    (1 << (tile.getLevelNumber()) + 3) - 1 - tile.getRow(),
                    (tile.getLevelNumber() + 3) 
                    );
            System.out.println(url);
            return new URL(url);
        }
    }

    @Override
    public String toString()
    {
        return "谷歌地圖影像";
    }
}
 

修改computeTextureTransform函式

注意，這裡是臨時改法，只是作為驗證，至於具體應用中程式碼肯定不是這麼亂寫，因為還要考慮其他不需要偏移的圖層，還有這個偏移好像只有在層級比較高的時候發生

在層級低的地方，即遠看地球的時候是不用偏移，這裡都沒有作判斷處理

protected void computeTextureTransform(DrawContext dc, SurfaceTile tile, Transform t)
    {
        Sector st1 = tile.getSector();
        Sector st = new Sector(st1.getMinLatitude().addDegrees(0.0029), st1.getMaxLatitude().addDegrees(0.0029), st1.getMinLongitude().addDegrees(-0.0045), st1.getMaxLongitude().addDegrees(-0.0045));
 

 protected Iterable<SurfaceTile> getIntersectingTiles(DrawContext dc, SectorGeometry sg,
        Iterable<? extends SurfaceTile> tiles)
    {
        ArrayList<SurfaceTile> intersectingTiles = null;

        for (SurfaceTile tile : tiles)
        {
            Sector st1 = tile.getSector();
            Sector st = new Sector(st1.getMinLatitude().addDegrees(0.0029), st1.getMaxLatitude().addDegrees(0.0029), st1.getMinLongitude().addDegrees(-0.0045), st1.getMaxLongitude().addDegrees(-0.0045));

private boolean isTileVisibleEx(DrawContext dc, MercatorTextureTile tile)
    {
        //        if (!(tile.getExtent(dc).intersects(dc.getView().getFrustumInModelCoordinates())
        //            && (dc.getVisibleSector() == null || dc.getVisibleSector().intersects(tile.getSector()))))
        //            return false;
        //
        //        Position eyePos = dc.getView().getEyePosition();
        //        LatLon centroid = tile.getSector().getCentroid();
        //        Angle d = LatLon.greatCircleDistance(eyePos.getLatLon(), centroid);
        //        if ((!tile.getLevelName().equals("0")) && d.compareTo(tile.getSector().getDeltaLat().multiply(2.5)) == 1)
        //            return false;
        //
        //        return true;
        //
        Sector st1 = tile.getSector();
        Sector st = new Sector(st1.getMinLatitude().addDegrees(0.0029).getDegrees() > 90.0 ? Angle.fromDegrees(90.0) : st1.getMinLatitude().addDegrees(0.0029),
            st1.getMaxLatitude().addDegrees(0.0029),
            st1.getMinLongitude().addDegrees(-0.0045).getDegrees() < -180.0 ? Angle.fromDegrees(-180.0) : st1.getMinLongitude().addDegrees(-0.0045),
            st1.getMaxLongitude().addDegrees(-0.0045));



        Extent et = Sector.computeBoundingBox(dc.getGlobe(), dc.getVerticalExaggeration(), /*this.getSector()*/st);

        return /*tile.getExtent(dc)*/et.intersects(
            dc.getView().getFrustumInModelCoordinates())
            && (dc.getVisibleSector() == null || dc.getVisibleSector()
            .intersects(/*tile.getSector()*/st));
    }