I can't understand the results of ST_Project:
- I use geography-type here, but the results are the same for geometry.
- I use a rather long distance, because I need, at least in one direction, for my application a large distance. Because of this I found the problem in the first place.
I just want to project a point towards North, East, South and West. With the direction north, everything is as I expect it:
SELECT ST_AsText(ST_Project('POINT(-30 -0.5)'::geography, 1e7, radians(0)));
st_astext
-----------------------------
POINT(-30 89.4874128664049)
But in the other directions, here for example East, I get this:
SELECT ST_AsText(ST_Project('POINT(-30 -0.5)'::geography, 1e7, radians(90)));
st_astext
---------------------------------------------
POINT(59.8315233716443 0.00116689648502556)
I think this should be POINT(59.8315233716443 -0.5)
This behaviour occurs in all directions save north.
I'm new to whole earth coordinate systems so maybe I missed something, but I thought that when one walks directly west (or south) one would, by definition, not leave the current longitude (or latitude)-line but only change the other.