I have been racking my brains for a little while to figure out a way of computing the area of a concave polygon. I already have code that copes with convex (by splitting into triangles) but obviously this will not work.
So far I have tried the following approaches:
- Project Lat Lon values via ESPG 3395. Use these values in cross product or alternatively use methodology explained here.
I have found several related stack overflow articles with answers but I don’t truely understand which is the most appropriate way.
To validate the answers, I’ve been using google my maps, with the coordinates added and a polygon drawn giving me the area in km^2.
Here are the related articles I’ve found:
Is projecting them and then using vector maths the most appropriate or am I required to use spherical maths?