3
votes
0answers
622 views

Bearing/Course/Heading in WGS84 ellipsoid model

There is a common formula for computing the initial bearing for a course from lat1, lon1 to lat2, lon2. (And yes, I'm aware that the course will change when traveling). atan2( sin(lon2-lon1) * ...
0
votes
1answer
499 views

Convert Lat/Lon to Pixel-XY on cropped map

I've got a little problem. I have a GPX-Track containing LatLon coordinates based on WGS84. The track should be drawn on a cropped map, and for this, I need the pixel coordinates. The map tiles are ...
2
votes
2answers
1k views

ST_Distance versus ST_Distance_Spheroid?

As my client software uses lat/lon coordinates when communicating with my (spherical mercator) postgis database i decided to ST_Transform every geometry to WGS-84. However i noticed that ST_Distance ...