title: Is there a Flutter package to calculate and draw the shortest path in a map that uses Mercator projection?
body: <p>I am trying to draw the shortest path between two cities inside the flutter_map plugin. flutter_map uses OpenStreetMaps which displays the map in Mercator projection and has a functionality called <code>polyline</code>, which allows to draw a line between a path of points. Now if I draw a line from one city to another city this shows up as a straight line on the map, which of course is not the shortest path, because of the projection.</p>
  <p>After some googling I found stuff like <a href="https://planetcalc.com/713/?license=1" rel="nofollow noreferrer">this</a> that looks quite math heavy and rather difficult to implement. Therefore I am wondering if there is a library that provides methods to calculate the shortest path in a Mercator projection or if there is another way to do that, that I am not aware of.</p>