Crs.Wgs84MercatorWeb Property
Gets a Crs using WGS84 and a MercatorProjection using sphere formulas.
Syntax
public static Crs Wgs84MercatorWeb { get; }Property Value
Remarks
The EPSG name for this Crs is "WGS 84 / Pseudo-Mercator", with code 3857.
When using WGS84 with a MercatorProjection, there are now two major alternatives:
this Crs, which assumes a spherical shape of the Earth.
the Wgs84MercatorEllipsoid, which assumes an ellipsoid shape of the Earth.
The ellipsoid choice is more traditional (at least since the 1800s) for large scale maps, and it is the only choice that gives a truly conformal map.
The spherical choice is more popular in web applications (Google Maps, Microsoft Virtual Earth, etc.), even though it is only approximately conformal.
For a world map, the differences are not visible to the naked eye, so for display purposes, you may as well choose the spherical formulas to improve efficiency. But if geodata are stored in Mercator coordinates, it is important to respect the choice of the data provider, since the difference can be up to about 20 km.
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Platforms
Windows, Linux, Android