4
votes
1answer
48 views

Should geometries be drawn using rhumb-line or great-circle paths?

I work with WGS-84 coordinates and, most of the time, my map display (luciadmap) is in Mercator projection. My client is surprised to see that, for a rectangular geometry: the line between the 2 ...
1
vote
1answer
28 views

Does PostGIS have a Vincenty Distance calculation?

I have compared some distance calculations between geopy and PostGIS ST_Distance_Sphere, and it seems that PostGIS ST_Distance uses a calculation that is similar to the great circle distance rather ...
6
votes
2answers
390 views

Find points of interest near a path?

Imagine a table of points of interest along with lat/long. The user identifies two of these points. I want to do the following: Calculate a great-circle path between these points Find all POIs that ...
5
votes
3answers
1k views

Is there a way to get ST_ClosestPoint for Geography type?

Using PostGIS 2.0.0 I'd like to find the point on a LINESTRING that is closest to a given point. The LINESTRING represents a great circle line (ie. geography type). ST_ClosestPoint appears to do ...