Near-sided perspective¶
The near-sided perspective projection simulates a view from a height \(h\) similar to how a satellite in orbit would see it.
Classification |
Azimuthal. Neither conformal nor equal area. |
Available forms |
Forward and inverse spherical projection |
Defined area |
Global, although for one hemisphere at a time. |
Alias |
nsper |
Domain |
2D |
Input type |
Geodetic coordinates |
Output type |
Projected coordinates |
proj-string: +proj=nsper +h=3000000 +lat_0=-20 +lon_0=145¶
Parameters¶
Required¶
- +h=<value>¶
Height of the view point above the Earth and must be in the same units as the radius of the sphere or semimajor axis of the ellipsoid.
Optional¶
- +lon_0=<value>¶
Central meridian/longitude of natural origin, longitude of origin or longitude of false origin (naming and meaning depend on the projection method).
Defaults to 0.0.
Note
The default convention is to interpret this value as decimal degrees. To specify radians instead, follow the value with the "r" character.
Example: +lon_0=1.570796r
See Projection Units for more information.
- +lat_0=<value>¶
Latitude of natural origin, latitude of false origin or latitude of projection centre (naming and meaning depend on the projection method).
Defaults to 0.0.
Note
The default convention is to interpret this value as decimal degrees. To specify radians instead, follow the value with the "r" character.
Example: +lat_0=1.570796r
See Projection Units for more information.
- +R=<value>¶
Radius of the sphere, given in meters. If used in conjunction with
+ellps,+Rtakes precedence.See Ellipsoid size parameters for more information.
- +x_0=<value>¶
False easting, easting at false origin or easting at projection centre (naming and meaning depend on the projection method). Always in meters.
Defaults to 0.0.
- +y_0=<value>¶
False northing, northing at false origin or northing at projection centre (naming and meaning depend on the projection method). Always in meters.
Defaults to 0.0.