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struct WebMercator12

(Niantic.Lightship.Maps.Core.Coordinates.WebMercator12)

Overview​

A type specifying location on the surface of the Earth in Web Mercator coordinates at zoom level 12: https://en.wikipedia.org/wiki/Web_Mercator_projection

struct WebMercator12 {
        // fields
    
         static const int ZOOM_LEVEL = 12;
         static const int MIN_TILE_COORD = 0;
         static const int MAX_TILE_COORD =(1<<ZOOM_LEVEL) - 1;
         static const double MIN_LATITUDE_DEGREES = Mercator.MIN_LATITUDE_DEGREES;
         static const double MAX_LATITUDE_DEGREES = Mercator.MAX_LATITUDE_DEGREES;
         readonly double East;
         readonly double North;
         readonly double Elevation;

        // methods
    
        WebMercator12(in Vector3D vec3);
        WebMercator12(Vector3 vec3);
        WebMercator12(double east, double elevation, double north);
        Vector3D ToVector3D();
        LatLng ToLatLng();
        override string ToString();
        static double WrapLongitudeDegrees(double longitudeDegrees);
        static double ClampLatitudeDegrees(double latitudeDegrees);
        static double WrapLongitudeCoord(double longitudeCoord);
        static double ClampLatitudeCoord(double latitudeCoord);
        static int WrapLongitudeCoord(int longitudeCoord);
        static int ClampLatitudeCoord(int latitudeCoord);
        static double FromLongitude(double longitudeDegrees);
        static double FromLatitude(double latitudeDegrees);
        static double ToLatitude(double latitudeCoord);
        static double ToLongitude(double x);
        static double GetMetersPerUnit(double latitudeDegrees);
    };

Detailed Documentation​

A type specifying location on the surface of the Earth in Web Mercator coordinates at zoom level 12: https://en.wikipedia.org/wiki/Web_Mercator_projection

East: Longitude -180 maps to 0. Longitude 180 maps to 4095.

North: Latitude ~ -85 maps to 0. Longitude ~ 85 maps to 4095.

Fields​

ZOOM_LEVEL​

static const int ZOOM_LEVEL = 12

The zoom level of a WebMercator12 coordinate (which is 12)

MIN_TILE_COORD​

static const int MIN_TILE_COORD = 0

The minimum tile coordinate value

MAX_TILE_COORD​

static const int MAX_TILE_COORD =(1<<ZOOM_LEVEL) - 1

The maximum tile coordinate value

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

East​

readonly double East

positive going East

North​

readonly double North

positive going North

Elevation​

readonly double Elevation

meters, positive going up

Methods​

WebMercator12​

WebMercator12(in Vector3D vec3)

Create a WebMercator12 coordinate from a Vector3 (of doubles) where x -> east y -> north z -> up

    Parameters:

    vec3 -

WebMercator12​

WebMercator12(Vector3 vec3)

Create a WebMercator12 coordinate from a Vector3 (of floats) where x -> east y -> north z -> up

    Parameters:

    vec3 -

WebMercator12​

WebMercator12(double east, double elevation, double north)

Create a WebMercator12 coordinate from north, east, and elevation

    Parameters:

    east -

    elevation -

    north -

ToVector3D​

Vector3D ToVector3D()

Convert to a Vector3D where east -> x north -> y up -> z

    Returns:

ToLatLng​

LatLng ToLatLng()

Converts a location in WebMercator12 coordinates to LatLng

    Returns:

    The current location in WebMercator12

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.

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

WrapLongitudeCoord​

static double WrapLongitudeCoord(double longitudeCoord)

Wraps a longitude (in tile coordinates) if it's outside of the range defined by MIN_TILE_COORD and MAX_TILE_COORD.

    Parameters:

    longitudeCoord - The longitude to wrap

    Returns:

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

ClampLatitudeCoord​

static double ClampLatitudeCoord(double latitudeCoord)

Clamps a latitude (in tile coordinates) to MIN_TILE_COORD if it's less than the minimum value, or to MAX_TILE_COORD if it's greater than the maximum value.

    Parameters:

    latitudeCoord - The latitude to clamp

    Returns:

    A latitude clamped to within the min and max

WrapLongitudeCoord​

static int WrapLongitudeCoord(int longitudeCoord)

Wraps a longitude (in tile coordinates) if it's outside of the range defined by MIN_TILE_COORD and MAX_TILE_COORD.

    Parameters:

    longitudeCoord - The longitude to wrap

    Returns:

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

ClampLatitudeCoord​

static int ClampLatitudeCoord(int latitudeCoord)

Clamps a latitude (in tile coordinates) to MIN_TILE_COORD if it's less than the minimum value, or to MAX_TILE_COORD if it's greater than the maximum value.

    Parameters:

    latitudeCoord - The latitude to clamp

    Returns:

    A latitude clamped to within the min and max

FromLongitude​

static double FromLongitude(double longitudeDegrees)

Converts a longitude from degrees to tile coordinates

    Parameters:

    longitudeDegrees -

    Returns:

FromLatitude​

static double FromLatitude(double latitudeDegrees)

Converts a latitude from degrees to tile coordinates

    Parameters:

    latitudeDegrees -

    Returns:

ToLatitude​

static double ToLatitude(double latitudeCoord)

Converts a latitude from tile coordinates to degrees

    Parameters:

    latitudeCoord -

    Returns:

ToLongitude​

static double ToLongitude(double x)

Converts a longitude from tile coordinates to degrees

    Parameters:

    x -

    Returns:

GetMetersPerUnit​

static double GetMetersPerUnit(double latitudeDegrees)

Returns ratio of meters to web mercator 12 units (distances in web mercator are stretched towards the poles)

    Parameters:

    latitudeDegrees - Latitude, in degrees