Map Projections
- 2 minutes to read
This topic describes map projections, lists their supported types, and explains how to create specializations of various projections in the Map Control.
Map projections provide numerous methods of representing a sphere surface, or any other three-dimensional body, on a plane. Each map projection distorts the surface in some manner. For instance, the distortion of the Mercator projection increases away from the equator, and is extreme in the polar regions. Thus, it is difficult to say which projection is superior. The best solution is to choose a projection that meets your specific requirements. For more information, refer to the “Map projection” online article at https://en.wikipedia.org/wiki/Map_projection.
The Map Control supports the following projections:
| Projection | Projection Preview |
|---|---|
| Braun stereographic |  |
| Elliptical Mercator |  |
| EPSG:4326 (also known as WGS 84 or WGS 1984) |  |
| Equal-area |  |
| Equirectangular |  |
| Kavrayskiy VII |  |
| Lambert cylindrical equal-area |  |
| Miller cylindrical |  |
| Sinusoidal |  |
| Spherical Mercator |  |
All layer types use the spherical Mercator projection by default. For the Item layers and Item File layers, you can switch from the default projection to any other supported projection using a map layer’s Projection, ProjectionClass, or ProjectionClassName property.
To make a map projection, specify the width and height for the projection using a map layer’s InitialMapSize property. The width/height aspect ratio corresponds to a certain specialization. For instance, you can learn about specializations and find their width/height aspect ratio values for the cylindrical equal-area projection in the “Cylindrical equal-area projection” online article at https://en.wikipedia.org/wiki/Cylindrical_equal-area_projection.