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Add MercatorTiledImageLayer support.
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+296
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7 files changed

+296
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‎worldwind/src/main/java/gov/nasa/worldwind/layer/mercator/MercatorImageTile.java

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package gov.nasa.worldwind.layer.mercator;
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import android.graphics.Bitmap;
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import java.util.Collection;
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import gov.nasa.worldwind.render.ImageTile;
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import gov.nasa.worldwind.util.DownloadPostprocessor;
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import gov.nasa.worldwind.util.Level;
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import gov.nasa.worldwind.util.LevelSet;
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import gov.nasa.worldwind.util.Logger;
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import gov.nasa.worldwind.util.Tile;
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import gov.nasa.worldwind.util.TileFactory;
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class MercatorImageTile extends ImageTile implements DownloadPostprocessor<Bitmap> {
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/**
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* Constructs a tile with a specified sector, level, row and column.
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*
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* @param sector the sector spanned by the tile
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* @param level the tile's level in a {@link LevelSet}
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* @param row the tile's row within the specified level
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* @param column the tile's column within the specified level
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*/
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MercatorImageTile(MercatorSector sector, Level level, int row, int column) {
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super(sector, level, row, column);
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}
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/**
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* Creates all Mercator tiles for a specified level within a {@link LevelSet}.
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*
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* @param level the level to create the tiles for
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* @param tileFactory the tile factory to use for creating tiles.
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* @param result an pre-allocated Collection in which to store the results
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*/
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static void assembleMercatorTilesForLevel(Level level, TileFactory tileFactory, Collection<Tile> result) {
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if (level == null) {
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throw new IllegalArgumentException(
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Logger.logMessage(Logger.ERROR, "Tile", "assembleTilesForLevel", "missingLevel"));
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}
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if (tileFactory == null) {
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throw new IllegalArgumentException(
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Logger.logMessage(Logger.ERROR, "Tile", "assembleTilesForLevel", "missingTileFactory"));
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}
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if (result == null) {
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throw new IllegalArgumentException(
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Logger.logMessage(Logger.ERROR, "Tile", "assembleTilesForLevel", "missingResult"));
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}
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// NOTE LevelSet.sector is final Sector attribute and thus can not be cast to MercatorSector!
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MercatorSector sector = MercatorSector.fromSector(level.parent.sector);
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double dLat = level.tileDelta / 2;
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double dLon = level.tileDelta;
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int firstRow = Tile.computeRow(dLat, sector.minLatitude());
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int lastRow = Tile.computeLastRow(dLat, sector.maxLatitude());
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int firstCol = Tile.computeColumn(dLon, sector.minLongitude());
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int lastCol = Tile.computeLastColumn(dLon, sector.maxLongitude());
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double deltaLat = dLat / 90;
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double d1 = sector.minLatPercent() + deltaLat * firstRow;
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for (int row = firstRow; row <= lastRow; row++) {
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double d2 = d1 + deltaLat;
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double t1 = sector.minLongitude() + (firstCol * dLon);
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for (int col = firstCol; col <= lastCol; col++) {
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double t2;
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t2 = t1 + dLon;
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result.add(tileFactory.createTile(MercatorSector.fromDegrees(d1, d2, t1, t2), level, row, col));
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t1 = t2;
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}
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d1 = d2;
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}
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}
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/**
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* Returns the four children formed by subdividing this tile. This tile's sector is subdivided into four quadrants
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* as follows: Southwest; Southeast; Northwest; Northeast. A new tile is then constructed for each quadrant and
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* configured with the next level within this tile's LevelSet and its corresponding row and column within that
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* level. This returns null if this tile's level is the last level within its {@link LevelSet}.
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*
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* @param tileFactory the tile factory to use to create the children
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*
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* @return an array containing the four child tiles, or null if this tile's level is the last level
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*/
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@Override
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public Tile[] subdivide(TileFactory tileFactory) {
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if (tileFactory == null) {
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throw new IllegalArgumentException(
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Logger.logMessage(Logger.ERROR, "Tile", "subdivide", "missingTileFactory"));
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}
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Level childLevel = this.level.nextLevel();
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if (childLevel == null) {
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return null;
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}
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MercatorSector sector = (MercatorSector) this.sector;
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double d0 = sector.minLatPercent();
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double d2 = sector.maxLatPercent();
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double d1 = d0 + (d2 - d0) / 2.0;
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double t0 = sector.minLongitude();
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double t2 = sector.maxLongitude();
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double t1 = 0.5 * (t0 + t2);
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int northRow = 2 * this.row;
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int southRow = northRow + 1;
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int westCol = 2 * this.column;
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int eastCol = westCol + 1;
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Tile[] children = new Tile[4];
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children[0] = tileFactory.createTile(MercatorSector.fromDegrees(d0, d1, t0, t1), childLevel, northRow, westCol);
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children[1] = tileFactory.createTile(MercatorSector.fromDegrees(d0, d1, t1, t2), childLevel, northRow, eastCol);
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children[2] = tileFactory.createTile(MercatorSector.fromDegrees(d1, d2, t0, t1), childLevel, southRow, westCol);
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children[3] = tileFactory.createTile(MercatorSector.fromDegrees(d1, d2, t1, t2), childLevel, southRow, eastCol);
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return children;
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}
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@Override
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public Bitmap process(Bitmap resource) {
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// Re-project mercator tile to equirectangular
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int[] pixels = new int[resource.getWidth() * resource.getHeight()];
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int[] result = new int[resource.getWidth() * resource.getHeight()];
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resource.getPixels(pixels, 0, resource.getWidth(), 0, 0, resource.getWidth(), resource.getHeight());
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double miny = ((MercatorSector) sector).minLatPercent();
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double maxy = ((MercatorSector) sector).maxLatPercent();
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for (int y = 0; y < resource.getHeight(); y++) {
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double sy = 1.0 - y / (double) (resource.getHeight() - 1);
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double lat = sy * (sector.maxLatitude() - sector.minLatitude()) + sector.minLatitude();
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double dy = 1.0 - (MercatorSector.gudermannianInverse(lat) - miny) / (maxy - miny);
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dy = Math.max(0.0, Math.min(1.0, dy));
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int iy = (int) (dy * (resource.getHeight() - 1));
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for (int x = 0; x < resource.getWidth(); x++) {
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result[x + y * resource.getWidth()] = pixels[x + iy * resource.getWidth()];
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}
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}
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return Bitmap.createBitmap(result, resource.getWidth(), resource.getHeight(), resource.getConfig());
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}
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}

‎worldwind/src/main/java/gov/nasa/worldwind/layer/mercator/MercatorSector.java

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package gov.nasa.worldwind.layer.mercator;
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import gov.nasa.worldwind.geom.Sector;
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public class MercatorSector extends Sector {
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private final double minLatPercent, maxLatPercent;
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private MercatorSector(double minLatPercent, double maxLatPercent,
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double minLongitude, double maxLongitude) {
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this.minLatPercent = minLatPercent;
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this.maxLatPercent = maxLatPercent;
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this.minLatitude = gudermannian(minLatPercent);
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this.maxLatitude = gudermannian(maxLatPercent);
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this.minLongitude = minLongitude;
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this.maxLongitude = maxLongitude;
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}
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public static MercatorSector fromDegrees(double minLatPercent, double maxLatPercent,
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double minLongitude, double maxLongitude) {
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return new MercatorSector(minLatPercent, maxLatPercent, minLongitude, maxLongitude);
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}
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static MercatorSector fromSector(Sector sector) {
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return new MercatorSector(gudermannianInverse(sector.minLatitude()),
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gudermannianInverse(sector.maxLatitude()),
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sector.minLongitude(), sector.maxLongitude());
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}
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static double gudermannianInverse(double latitude) {
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return Math.log(Math.tan(Math.PI / 4.0 + Math.toRadians(latitude) / 2.0)) / Math.PI;
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}
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private static double gudermannian(double percent) {
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return Math.toDegrees(Math.atan(Math.sinh(percent * Math.PI)));
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}
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double minLatPercent() {
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return minLatPercent;
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}
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double maxLatPercent()
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{
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return maxLatPercent;
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}
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}

‎worldwind/src/main/java/gov/nasa/worldwind/layer/mercator/MercatorTiledImageLayer.java

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package gov.nasa.worldwind.layer.mercator;
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import gov.nasa.worldwind.WorldWind;
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import gov.nasa.worldwind.geom.Sector;
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import gov.nasa.worldwind.layer.RenderableLayer;
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import gov.nasa.worldwind.render.ImageOptions;
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import gov.nasa.worldwind.render.ImageSource;
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import gov.nasa.worldwind.util.Level;
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import gov.nasa.worldwind.util.LevelSet;
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import gov.nasa.worldwind.util.Tile;
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import gov.nasa.worldwind.util.TileFactory;
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public abstract class MercatorTiledImageLayer extends RenderableLayer implements TileFactory {
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private static final double FULL_SPHERE = 360;
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private final int firstLevelOffset;
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public MercatorTiledImageLayer(String name, int numLevels, int firstLevelOffset, int tileSize, boolean overlay) {
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super(name);
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this.setPickEnabled(false);
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this.firstLevelOffset = firstLevelOffset;
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MercatorTiledSurfaceImage surfaceImage = new MercatorTiledSurfaceImage();
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surfaceImage.setLevelSet(new LevelSet(
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MercatorSector.fromDegrees(-1.0, 1.0, - FULL_SPHERE / 2, FULL_SPHERE / 2),
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FULL_SPHERE / (1 << firstLevelOffset), numLevels - firstLevelOffset, tileSize, tileSize));
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surfaceImage.setTileFactory(this);
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if(!overlay) {
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surfaceImage.setImageOptions(new ImageOptions(WorldWind.RGB_565)); // reduce memory usage by using a 16-bit configuration with no alpha
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}
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this.addRenderable(surfaceImage);
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}
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@Override
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public Tile createTile(Sector sector, Level level, int row, int column) {
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MercatorImageTile tile = new MercatorImageTile((MercatorSector) sector, level, row, column);
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tile.setImageSource(ImageSource.fromUrl(getImageSourceUrl(column, (1 << (level.levelNumber + firstLevelOffset)) - 1 - row, level.levelNumber + firstLevelOffset), tile));
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return tile;
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}
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protected abstract String getImageSourceUrl(int x, int y, int z);
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}

‎worldwind/src/main/java/gov/nasa/worldwind/layer/mercator/MercatorTiledSurfaceImage.java

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package gov.nasa.worldwind.layer.mercator;
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import gov.nasa.worldwind.shape.TiledSurfaceImage;
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import gov.nasa.worldwind.util.Level;
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public class MercatorTiledSurfaceImage extends TiledSurfaceImage {
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@Override
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protected void createTopLevelTiles() {
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Level firstLevel = this.levelSet.firstLevel();
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if (firstLevel != null) {
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MercatorImageTile.assembleMercatorTilesForLevel(firstLevel, this.tileFactory, this.topLevelTiles);
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}
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}
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}

‎worldwind/src/main/java/gov/nasa/worldwind/render/ImageRetriever.java

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import java.net.URLConnection;
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import gov.nasa.worldwind.WorldWind;
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import gov.nasa.worldwind.util.DownloadPostprocessor;
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import gov.nasa.worldwind.util.Logger;
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import gov.nasa.worldwind.util.Retriever;
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import gov.nasa.worldwind.util.WWUtil;
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}
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7475
if (imageSource.isUrl()) {
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return this.decodeUrl(imageSource.asUrl(), imageOptions);
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return this.decodeUrl(imageSource.asUrl(), imageOptions, imageSource.postprocessor);
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}
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return this.decodeUnrecognized(imageSource);
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return BitmapFactory.decodeFile(pathName, factoryOptions);
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}
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protected Bitmap decodeUrl(String urlString, ImageOptions imageOptions) throws IOException {
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protected Bitmap decodeUrl(String urlString, ImageOptions imageOptions, DownloadPostprocessor<Bitmap> postprocessor) throws IOException {
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// TODO establish a file caching service for remote resources
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// TODO retry absent resources, they are currently handled but suppressed entirely after the first failure
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// TODO configurable connect and read timeouts
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stream = new BufferedInputStream(conn.getInputStream());
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BitmapFactory.Options factoryOptions = this.bitmapFactoryOptions(imageOptions);
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return BitmapFactory.decodeStream(stream, null, factoryOptions);
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Bitmap bitmap = BitmapFactory.decodeStream(stream, null, factoryOptions);
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// Apply bitmap transformation if required
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if (postprocessor != null && bitmap != null) {
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bitmap = postprocessor.process(bitmap);
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}
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return bitmap;
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} finally {
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WWUtil.closeSilently(stream);
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}

‎worldwind/src/main/java/gov/nasa/worldwind/render/ImageSource.java

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import java.util.Arrays;
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import java.util.HashMap;
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import gov.nasa.worldwind.util.DownloadPostprocessor;
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import gov.nasa.worldwind.util.Logger;
1617
import gov.nasa.worldwind.util.WWUtil;
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protected Object source;
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protected DownloadPostprocessor<Bitmap> postprocessor;
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protected ImageSource() {
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}
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return imageSource;
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}
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/**
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* Constructs an image source with a URL string. The image's dimensions should be no greater than 2048 x 2048. The
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* application's manifest must include the permissions that allow network connections.
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*
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* @param urlString complete URL string
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* @param postprocessor implementation of image post-transformation routine
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*
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* @return the new image source
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*
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* @throws IllegalArgumentException If the URL string is null
189+
*/
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public static ImageSource fromUrl(String urlString, DownloadPostprocessor<Bitmap> postprocessor) {
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ImageSource imageSource = fromUrl(urlString);
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imageSource.postprocessor = postprocessor;
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return imageSource;
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}
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/**
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* Constructs a bitmap image source with a line stipple pattern. The result is a one-dimensional bitmap with pixels
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* representing the specified stipple factor and stipple pattern. Line stipple images can be used for displaying

‎worldwind/src/main/java/gov/nasa/worldwind/util/DownloadPostprocessor.java

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package gov.nasa.worldwind.util;
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/**
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* Interface for resource download post-processing
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*/
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public interface DownloadPostprocessor<T> {
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/**
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* Process resource according to specified algorithm implementation
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*
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* @param resource original resource
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* @return processed resource
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*/
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T process(T resource);
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}

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