Mapping with Drupal

Appendix B. Map Projections

This appendix describes some common and uncommon map projections. Introduced in Projections and Coordinate Systems, map projections are the many different ways of translating the shape of the Earth, which is like sphere, onto a flat surface.

Note

For a much more in-depth look at the many different kinds of projections there are and what benefits and disadvantages they possess, with pictures, Map Thematics has an amazing list of projections.

WGS 84 (Latitude and Longitude)

The World Geodetic System (19)84 projection is a variant of the Mercator projection, but without the assumption that the Earth is a sphere (actually an ellipsoid). This is the projection that GPS systems use. It has the same limitations of the Spherical Mercator that were discussed in Projections and Coordinate Systems. When you get to the local level of detail on a map, you will find slight differences in position from the spherical Mercator.

Note

The WGS 84 projection has the EPSG:4316 identifier.