Multi-map MapFileTileSource.setPriority (#1176)

docs/Changelog.md

@@ -2,6 +2,7 @@
 
 ## Next version
 
+- Multi-map `MapFileTileSource.setPriority` [#1176](https://github.com/mapsforge/vtm/pull/1176)
 - Color filter theme resources [#1175](https://github.com/mapsforge/vtm/pull/1175)
   - `ThemeCallback.getBitmap`
 - Update JTS, OkHttp dependencies [#1172](https://github.com/mapsforge/vtm/pull/1172) [#1173](https://github.com/mapsforge/vtm/pull/1173)

vtm-playground/src/org/oscim/test/MapsforgeTest.java

@@ -65,6 +65,8 @@ public void createLayers() {
         for (File mapFile : mapFiles) {
             MapFileTileSource mapFileTileSource = new MapFileTileSource();
             mapFileTileSource.setMapFile(mapFile.getAbsolutePath());
+            if ("world.map".equalsIgnoreCase(mapFile.getName()))
+                mapFileTileSource.setPriority(-1);
             tileSource.add(mapFileTileSource);
         }
         //tileSource.setDeduplicate(true);

vtm/src/org/oscim/core/BoundingBox.java

@@ -102,6 +102,26 @@ public BoundingBox(List<GeoPoint> geoPoints) {
         this.maxLongitudeE6 = maxLon;
     }
 
+    /**
+     * @param latitude  the latitude coordinate in degrees.
+     * @param longitude the longitude coordinate in degrees.
+     * @return true if this BoundingBox contains the given coordinates, false otherwise.
+     */
+    public boolean contains(double latitude, double longitude) {
+        return this.getMinLatitude() <= latitude && this.getMaxLatitude() >= latitude
+                && this.getMinLongitude() <= longitude && this.getMaxLongitude() >= longitude;
+    }
+
+    /**
+     * @param latitudeE6  the latitude coordinate in microdegrees (degrees * 10^6).
+     * @param longitudeE6 the longitude coordinate in microdegrees (degrees * 10^6).
+     * @return true if this BoundingBox contains the given coordinates, false otherwise.
+     */
+    public boolean contains(int latitudeE6, int longitudeE6) {
+        return this.minLatitudeE6 <= latitudeE6 && this.maxLatitudeE6 >= latitudeE6
+                && this.minLongitudeE6 <= longitudeE6 && this.maxLongitudeE6 >= longitudeE6;
+    }
+
     /**
      * @param geoPoint the point whose coordinates should be checked.
      * @return true if this BoundingBox contains the given GeoPoint, false

vtm/src/org/oscim/tiling/source/mapfile/MapDatabase.java

@@ -222,6 +222,14 @@ public class MapDatabase implements ITileDataSource {
 
     private boolean deduplicate;
 
+    /**
+     * Priority of this MapDatabase. A higher number means a higher priority. Negative numbers have a special
+     * meaning, they should only be used for so-called background maps. Data from background maps is only read
+     * if no other map has provided a (complete) map tile. The most famous example of a background map is a
+     * low-resolution world map. The default priority is 0.
+     */
+    private int priority = 0;
+
     public MapDatabase(MapFileTileSource tileSource) throws IOException {
         mTileSource = tileSource;
         try {
@@ -426,6 +434,31 @@ void setDeduplicate(boolean deduplicate) {
         this.deduplicate = deduplicate;
     }
 
+    /**
+     * Returns the priority of this MapDatabase. A higher number means a higher priority. Negative numbers
+     * have a special meaning, they should only be used for so-called background maps. Data from background
+     * maps is only read if no other map has provided a (complete) map tile. The most famous example of a
+     * background map is a low-resolution world map.
+     *
+     * @return The priority of this MapDatabase. Default is 0.
+     */
+    public int getPriority() {
+        return priority;
+    }
+
+    /**
+     * Sets the priority of this MapDatabase. A higher number means a higher priority. Negative numbers have
+     * a special meaning, they should only be used for so-called background maps. Data from background maps is
+     * only read if no other map has provided a (complete) map tile. The most famous example of a background
+     * map is a low-resolution world map. The default priority is 0.
+     *
+     * @param priority Priority of this MapDatabase. Negative number means background map priority (see above
+     *                 for the description).
+     */
+    public void setPriority(int priority) {
+        this.priority = priority;
+    }
+
     private void setTileClipping(QueryParameters queryParameters, SubFileParameter subFileParameter,
                                  long currentRow, long currentCol) {
         long numRows = queryParameters.toBlockY - queryParameters.fromBlockY;
@@ -1239,8 +1272,48 @@ public void restrictToZoomRange(int minZoom, int maxZoom) {
      * @return true if tile is part of database.
      */
     public boolean supportsTile(Tile tile) {
-        return tile.getBoundingBox().intersects(mTileSource.getMapInfo().boundingBox)
-                && (tile.zoomLevel >= this.zoomLevelMin && tile.zoomLevel <= this.zoomLevelMax);
+        return supportsArea(tile.getBoundingBox(), tile.zoomLevel);
+    }
+
+    /**
+     * Returns true if MapDatabase contains a complete tile.
+     *
+     * @param tile tile to be rendered.
+     * @return true if complete tile is part of database.
+     */
+    public boolean supportsFullTile(Tile tile) {
+        return supportsFullArea(tile.getBoundingBox(), tile.zoomLevel);
+    }
+
+    /**
+     * Returns true if MapDatabase covers (even partially) certain area in required zoom level.
+     *
+     * @param boundingBox area we test
+     * @param zoomLevel   zoom level we test
+     * @return true if area is part of the database.
+     */
+    public boolean supportsArea(BoundingBox boundingBox, int zoomLevel) {
+        return boundingBox.intersects(mTileSource.getMapInfo().boundingBox)
+                && (zoomLevel >= this.zoomLevelMin && zoomLevel <= this.zoomLevelMax);
+    }
+
+    /**
+     * Returns true if MapDatabase covers certain area completely in required zoom level.
+     *
+     * @param boundingBox area we test
+     * @param zoomLevel   zoom level we test
+     * @return true if complete area is part of the database.
+     */
+    public boolean supportsFullArea(BoundingBox boundingBox, int zoomLevel) {
+        final BoundingBox bbox1 = mTileSource.getMapInfo().boundingBox;
+        final BoundingBox bbox2 = boundingBox;
+        return bbox1.intersects(bbox2)
+                && zoomLevel >= this.zoomLevelMin
+                && zoomLevel <= this.zoomLevelMax
+                && bbox1.contains(bbox2.maxLatitudeE6, bbox2.maxLongitudeE6)
+                && bbox1.contains(bbox2.minLatitudeE6, bbox2.minLongitudeE6)
+                && bbox1.contains(bbox2.maxLatitudeE6, bbox2.minLongitudeE6)
+                && bbox1.contains(bbox2.minLatitudeE6, bbox2.maxLongitudeE6);
     }
 
     /**

vtm/src/org/oscim/tiling/source/mapfile/MapFileTileSource.java

@@ -54,6 +54,14 @@ public class MapFileTileSource extends TileSource implements IMapFileTileSource
     private String preferredLanguage;
     private Callback callback;
 
+    /**
+     * Priority of this MapFileTileSource. A higher number means a higher priority. Negative numbers have a special
+     * meaning, they should only be used for so-called background maps. Data from background maps is only read
+     * if no other map has provided a (complete) map tile. The most famous example of a background map is a
+     * low-resolution world map. The default priority is 0.
+     */
+    private int priority = 0;
+
     public MapFileTileSource() {
         this(Viewport.MIN_ZOOM_LEVEL, Viewport.MAX_ZOOM_LEVEL);
     }
@@ -106,6 +114,31 @@ public void setPreferredLanguage(String preferredLanguage) {
         this.preferredLanguage = preferredLanguage;
     }
 
+    /**
+     * Returns the priority of this MapFileTileSource. A higher number means a higher priority. Negative numbers
+     * have a special meaning, they should only be used for so-called background maps. Data from background
+     * maps is only read if no other map has provided a (complete) map tile. The most famous example of a
+     * background map is a low-resolution world map.
+     *
+     * @return The priority of this MapFileTileSource. Default is 0.
+     */
+    public int getPriority() {
+        return priority;
+    }
+
+    /**
+     * Sets the priority of this MapFileTileSource. A higher number means a higher priority. Negative numbers have
+     * a special meaning, they should only be used for so-called background maps. Data from background maps is
+     * only read if no other map has provided a (complete) map tile. The most famous example of a background
+     * map is a low-resolution world map. The default priority is 0.
+     *
+     * @param priority Priority of this MapFileTileSource. Negative number means background map priority (see above
+     *                 for the description).
+     */
+    public void setPriority(int priority) {
+        this.priority = priority;
+    }
+
     @Override
     public OpenResult open() {
         if (mapFileInputStream == null && !options.containsKey("file"))