Processing Digital Maps - Programming GPS and OpenStreetMap Applications with Java - page 101

the details of the map, and it is a good idea to test with a limited number
of zoom levels.
A small area like RGB can produce a lot of data:

Tiles folder:
1,069 Folders
235,923 Files
2,700,925,950 Bytes ~ 2.5 gig

The time consumption for eighteen layers can be significant:

level 0-15: 0:56 - 1:19 = 23 minutes !
level 16: 1:19 - 2:30 = 1h 11
level 17: 2:30 - 7:30 = 5h 00
---------------------------------
total: 0h56min - 7h30min = 6 and one half hours !!

After some experimenting, all osm files and the Tiles folder can be
removed again and now createRGB.bat can run all the way. In the con-
text of a map compiler, the creation of products like createRGB.bat and
createRGB-NW.bat can be run in parallel, if the hardware allows this.

TileMapViewer . We now go back to the two applications MapViewer and
MovingObjects described on page 76, and enable the viewer to display the
tiles 12 created above.
The packaging of roaf.book.ro.MovingObjects.java , roafx.swingmap
.MapViewer.java , and roaf.book.map.osm.TileMapViewer.java is important
in the larger project context:

ˆ MovingObjects is real-object specific;

ˆ the MapViewer is an external observer to real objects;

ˆ the TileMapViewer is an OSM-specific add-on.

The implementation of the TileMapServer is straightforward:

1. The menuTileManger() instantiates a newTileMapServer(tilesDir)
to read the tile directory.

2. The TileMapServer goes through the zoomlevels 0 to 17 to createTiled
Maps for each existing directory.

3. The constructor of each TiledMap iterates through all subdirectories
to allocate the images according to the vertical and horizontal matrix.

4. Since all tiles have the same pixel size only the very first image is
loaded to get the horizontal and vertical pixel lengths.

12 Find the tiles in ../resources/gps/RGB-BUELL/Tiles .