| pe_loxodrome_coordinate | |
Finds the point at some distance and azimuth from a point along a loxodrome
void pe_loxodrome_coordinate (double a, double e2, double lam1, double phi1, double distance, double az12, double *lam2, double *phi2);
| a | Semimajor axis of the spheroid |
| e2 | Eccentricity squared of the spheroid |
| lam1 | Longitude value of the first point |
| phi1 | Latitude value of the first point |
| distance | Distance |
| az12 | Azimuth from from the first to the second point |
| lam2 | Longitude value of the new point |
| phi2 | Latitude value of the new point |
The pe_loxodrome_coordinate function takes a spheroid, point, distance, and azimuth and calculates the target point. A loxodrome, or rhumb line, is the path of equal bearing between two points on a spheroid. The Mercator projection has the special property that straight lines are loxodromes. This property makes the Mercator projection useful when navigating a course. Set e2 to zero to calculate distances on a sphere. The geographic coordinates and the azimuth are in radians. The azimuth value range is -π ≤ azimuth ≤ +π. An azimuth is measured positive clockwise with North equal to a zero azimuth. The semimajor axis (a) and the distance are usually given in meters. You can use any linear unit of measure as long as both values use the same unit of measure.
Longitude and latitude (in radians) of the new point