How to get latitude, longitude maximum and minimum from a center point

Question

I have a Geopoint that is the current position of the user. I know its latitude and longitude. I would like to get a square perimeter 50km around the user position so I need to know what are the min & max latitude and the min&max longitude around that given poin, in java. May someone helps me out with that ? Thanks in advance ?

Answer 1

Just found out the solution. If you have a given point P(lat, long). If you need to get 50 km around square perimeter for example, you need to take in consideration earth radius. Below how to do it:

double R = 6371; // earth radius in km
double radius = 50; // km
double latMin = lon - Math.toDegrees(radius/R/Math.cos(Math.toRadians(lat)));
double latMax = lon + Math.toDegrees(radius/R/Math.cos(Math.toRadians(lat)));
double longMax = lat + Math.toDegrees(radius/R);
double longMin = lat - Math.toDegrees(radius/R);

The real answer is here: credit to the real answerer