Predefined Ellipsoids
The maps package contains a list of predefined ellipsoids. A predefined ellipsoid is referenced by its name. To access a predefined ellipsoid, use the static method GetRegisteredEllipsoid of the class IlvEllipsoid.
For example:
|
const IlvEllipsoid* ellipsoid = IlvEllipsoid::GetRegisteredEllipsoid("clrk66"); IlvProjection* projection = new IlvMercatorProjection(); projection->setEllipsoid(*ellipsoid); |
The following table provides a list of the predefined ellipsoids that are available.
|
Name |
Comment |
Semi-Major Axis |
Eccentricity |
|
sphere |
Sphere of 6370997 m | 6370997.0 | 0.0 |
| MERIT | MERIT 1983 | 6378137.0 | 0.0818192 |
| SGS85 | Soviet Geodetic System 85 | 6378136.0 | 0.0818192 |
| GRS80 | GRS 1980(IUGG, 1980) | 6378137.0 | 0.0818192 |
| IAU76 | IAU 1976 | 6378140.0 | 0.0818192 |
| airy | Airy 1830 | 6377563.396 | 0.0816734 |
| APL4.9 | Appl. Physics. 1965 | 6378137.0 | 0.0818202 |
| NWL9D | Naval Weapons Lab., 1965 | 6378145.0 | 0.0818202 |
| mod_airy | Modified Airy | 6377340.189 | 0.0816734 |
| andrae | Andrae 1876 (Den., Iclnd.) | 6377104.43 | 0.0815816 |
| aust_SA | Australian Natl & S. Amer. 1969 | 6378160.0 | 0.0818202 |
| GRS67 | GRS 67(IUGG 1967) | 6378160.0 | 0.0818206 |
| bessel | Bessel 1841 | 6377397.155 | 0.0816968 |
| bess_nam | Bessel 1841 (Namibia) | 6377483.865 | 0.0816968 |
| clrk66 | Clarke 1866 | 6378206.4 | 0.0822719 |
| clrk80 | Clarke 1880 mod. | 6378249.145 | 0.0824832 |
| CPM | Commission des Poids et Mesures (1799) | 6375738.7 | 0.0772909 |
| delmbr | Delambre 1810 (Belgium) | 6376428.0 | 0.080064 |
| engelis | Engelis 1985 | 6378136.05 | 0.0818193 |
| evrst30 | Everest 1830 | 6377276.345 | 0.081473 |
| evrst48 | Everest 1948 | 6377304.063 | 0.081473 |
| evrst56 | Everest 1956 | 6377301.243 | 0.081473 |
| evrst69 | Everest 1969 | 6377295.664 | 0.081473 |
| evrstSS | Everest (Sabah & Sarawak) | 6377298.556 | 0.081473 |
| fschr60 | Fischer (Mercury Datum) 1960 | 6378166.0 | 0.0818133 |
| fschr60m | Modified Fischer 1960 | 6378155.0 | 0.0818133 |
| fschr68 | Fischer 1968 | 6378150.0 | 0.0818133 |
| helmert | Helmert 1906 | 6378200.0 | 0.0818133 |
| hough | Hough | 6378270.0 | 0.0819919 |
| intl | International 1909 (Hayford) | 6378388.0 | 0.0819919 |
| krass | Krassovsky, 1942 | 6378245.0 | 0.0818133 |
| kaula | Kaula 1961 | 6378163.0 | 0.0818215 |
| lerch | Lerch 1979 | 6378139.0 | 0.0818192 |
| mprts | Maupertius 1738 | 6397300.0 | 0.1021949 |
| new_intl | New International 1967 | 6378157.5 | 0.0818202 |
| plessis | Plessis 1817 (France) | 6376523.0 | 0.0804333 |
| SEasia | Southeast Asia | 6378155.0 | 0.0818133 |
| walbeck | Walbeck | 6376896.0 | 0.0812068 |
| WGS60 | WGS 60 | 6378165.0 | 0.0818133 |
| WGS66 | WGS 66 | 6378145.0 | 0.0818202 |
| WGS72 | WGS 72 | 6378135.0 | 0.0818188 |
| WGS84 | WGS 84 | 6378137.0 | 0.0818192 |
