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class WebMercator

(Niantic.Lightship.Maps.Core.Coordinates.WebMercator)

Overview​

A utility class for coordinate conversion to and from the Web Mercator projection, which represents a location on the surface of the Earth.

class WebMercator {
	public:
		// fields
	
		 static const double MIN_LATITUDE_DEGREES = Mercator.MIN_LATITUDE_DEGREES;
		 static const double MAX_LATITUDE_DEGREES = Mercator.MAX_LATITUDE_DEGREES;
		 static const long MIN_TILE_COORD = 0;

		// methods
	
		static int MaxTileCoord(int zoomLevel);
		static double WrapLongitudeDegrees(double longitudeDegrees);
		static double WrapLongitudeCoord(double longitude, int zoomLevel);
		static double ClampLatitudeDegrees(double latitudeDegrees);
		static double ClampLatitudeCoord(double latitude, int zoomLevel);
		static double FromLongitude(double longitudeDegrees, int zoomLevel);
		static double ToWrappedLongitude(double longitudeCoord, int zoomLevel);
		static double ToLongitude(double longitudeCoord, int zoomLevel);
		static double FromLatitude(double latitudeDegrees, int zoomLevel);
		static double ToClampedLatitude(double latitudeCoord, int zoomLevel);
		static double ToLatitude(double latitudeCoord, int zoomLevel);
		static long TileIndex(double pixels, double tileSize);
		static double ToZoomLevel(double metersPerPixel, double latitude);
		static double GetMetersPerUnit(double latitude, double zoomLevel);
	};

Detailed Documentation​

A utility class for coordinate conversion to and from the Web Mercator projection, which represents a location on the surface of the Earth.

Fields​

MIN_LATITUDE_DEGREES​

static const double MIN_LATITUDE_DEGREES = Mercator.MIN_LATITUDE_DEGREES

The minimum latitude supported by the projection, in degrees

MAX_LATITUDE_DEGREES​

static const double MAX_LATITUDE_DEGREES = Mercator.MAX_LATITUDE_DEGREES

The maximum latitude supported by the projection, in degrees

MIN_TILE_COORD​

static const long MIN_TILE_COORD = 0

The minimum tile coordinate at all zoom levels

Methods​

MaxTileCoord​

static int MaxTileCoord(int zoomLevel)

The maximum tile coordinate at a given zoom level

    Parameters:

    zoomLevel -

WrapLongitudeDegrees​

static double WrapLongitudeDegrees(double longitudeDegrees)

Wraps a longitude (in degrees) if it's outside of the range defined by LatLng.MIN_LONGITUDE_DEGREES and LatLng.MAX_LONGITUDE_DEGREES.

    Parameters:

    longitudeDegrees - The longitude to wrap

    Returns:

    A longitude wrapped around the globe such that it fits within the valid range of longitudes.

WrapLongitudeCoord​

static double WrapLongitudeCoord(double longitude, int zoomLevel)

Wraps a longitude (in tile coordinates) if it's outside of the range defined by MIN_TILE_COORD and the maximum tile coordinate value for a given zoom level.

    Parameters:

    longitude - The longitude to wrap

    zoomLevel - The coordinate's zoom level

    Returns:

    A longitude wrapped around the globe such that it fits within the valid range of longitudes.

ClampLatitudeDegrees​

static double ClampLatitudeDegrees(double latitudeDegrees)

Clamps a latitude (in degrees) to MIN_LATITUDE_DEGREES if it's less than the minimum value, or to MAX_LATITUDE_DEGREES if it's greater than the maximum value.

    Parameters:

    latitudeDegrees - The latitude to clamp

    Returns:

    A latitude clamped to within the min and max

ClampLatitudeCoord​

static double ClampLatitudeCoord(double latitude, int zoomLevel)

Clamps a latitude (in tile coordinates) to MIN_TILE_COORD if it's less than the minimum value, or to MaxTileCoord(int) if it's greater than the maximum value for a given zoom level.

    Parameters:

    latitude - The latitude to clamp

    zoomLevel - The coordinate's zoom level

    Returns:

    A latitude clamped to within the min and max

FromLongitude​

static double FromLongitude(double longitudeDegrees, int zoomLevel)

Converts a longitude from degrees to tile coordinates

    Parameters:

    longitudeDegrees -

    zoomLevel -

    Returns:

    

ToWrappedLongitude​

static double ToWrappedLongitude(double longitudeCoord, int zoomLevel)

Converts a longitude from tile coordinates to degrees, and wraps the value if necessary.

    Parameters:

    longitudeCoord - The longitude to convert

    zoomLevel - The coordinate's zoom level

    Returns:

    A longitude wrapped around the globe such that it fits within the valid range of longitudes.

ToLongitude​

static double ToLongitude(double longitudeCoord, int zoomLevel)

Converts a longitude from tile coordinates to degrees

    Parameters:

    longitudeCoord - The longitude to convert

    zoomLevel - The coordinate's zoom level

    Returns:

    

FromLatitude​

static double FromLatitude(double latitudeDegrees, int zoomLevel)

Converts a latitude from degrees to tile coordinates

    Parameters:

    latitudeDegrees - The latitude to convert

    zoomLevel - The coordinate's zoom level

    Returns:

    

ToClampedLatitude​

static double ToClampedLatitude(double latitudeCoord, int zoomLevel)

Converts a latitude from tile coordinates to degrees, and clamps the value if necessary

    Parameters:

    latitudeCoord - The latitude to convert

    zoomLevel - The coordinate's zoom level

    Returns:

    

ToLatitude​

static double ToLatitude(double latitudeCoord, int zoomLevel)

Converts a latitude from tile coordinates to degrees

    Parameters:

    latitudeCoord - The latitude to convert

    zoomLevel - The coordinate's zoom level

    Returns:

    

TileIndex​

static long TileIndex(double pixels, double tileSize)

Converts a coordinate in tile space into a tile index.

    Parameters:

    pixels -

    tileSize -

    Returns:

    

ToZoomLevel​

static double ToZoomLevel(double metersPerPixel, double latitude)

Converts a distance in meters represented by a pixel to a zoom level and back.

    Parameters:

    metersPerPixel -

    latitude -

    Returns:

    

GetMetersPerUnit​

static double GetMetersPerUnit(double latitude, double zoomLevel)

Returns ratio of meters to web mercator units (distances in web mercator are stretched towards the poles)

    Parameters:

    latitude -

    zoomLevel -

    Returns: