org.geotools.tile

Class TileFactory

Object

TileFactory

Direct Known Subclasses:

WebMercatorTileFactory, WMTSTileFactory

public abstract class TileFactory
extends Object

A TileFactory is responsible for finding and/or creating tiles for a given TileService and area. Here we make no distinction whereas a requested tile is created or retrieved form an internal cache.

When creating/finding a tile, the factory must know the zoom level for which the tile is required. Also, a geographic position or, alternatively a reference tile, must be passed.

Since:

12

Author:

Tobias Sauerwein, Ugo Taddei

Constructor Summary

Constructors

Constructor and Description
TileFactory()

Method Summary

Modifier and Type	Method and Description
abstract Tile	findLowerNeighbour(Tile tile, TileService service) Finds the tile for a service at the given position and zoom level, which is immediately below the the passed tile.
abstract Tile	findRightNeighbour(Tile tile, TileService service) Finds the tile for a service at the given position and zoom level, which is immediately to the right of the passed tile.
abstract Tile	findTileAtCoordinate(double lon, double lat, ZoomLevel zoomLevel, TileService service) Finds the tile for a service at the given position and zoom level.
abstract ZoomLevel	getZoomLevel(int zoomLevel, TileService service) Gets the ZoomLevel (object) for a given zoom level integer.
static double	normalizeDegreeValue(double value, int maxValue) Some clients, e.g. uDig, may produce numbers like -210° for the longitude, but we need a number in the range -180 to 180, so instead of -210 we want 150.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TileFactory

public TileFactory()

Method Detail

findTileAtCoordinate

public abstract Tile findTileAtCoordinate(double lon,
                                          double lat,
                                          ZoomLevel zoomLevel,
                                          TileService service)

Finds the tile for a service at the given position and zoom level.

Parameters:

lon - the longitude

lat - the latitude

zoomLevel - the zoom level

service - the service

Returns:

a tile

getZoomLevel

public abstract ZoomLevel getZoomLevel(int zoomLevel,
                                       TileService service)

Gets the ZoomLevel (object) for a given zoom level integer.

Parameters:

zoomLevel - the zoom level

service - the service

Returns:

a zoom level

findRightNeighbour

public abstract Tile findRightNeighbour(Tile tile,
                                        TileService service)

Finds the tile for a service at the given position and zoom level, which is immediately to the right of the passed tile.

Parameters:

tile - the reference tile

service -

Returns:

findLowerNeighbour

public abstract Tile findLowerNeighbour(Tile tile,
                                        TileService service)

Finds the tile for a service at the given position and zoom level, which is immediately below the the passed tile.

Parameters:

tile - the reference tile

service -

Returns:

normalizeDegreeValue

public static double normalizeDegreeValue(double value,
                                          int maxValue)

Some clients, e.g. uDig, may produce numbers like -210° for the longitude, but we need a number in the range -180 to 180, so instead of -210 we want 150.

Parameters:

value - the number to normalize (e.g. -210)

maxValue - the maximum value (e.g. 180 -> the range is: -180..180)

Returns:

a number between (-maxvalue) and maxvalue