My app (a flight tracker) needs to draw a line between two points (cities say) on a sphere (earth) along the surface (i.e. the great circle route) using Three.js. I can think of 2 ways - (a) creating Three.js 'Line' with a set of (enough) points that I calculate manually and (b) writing the lines into the texture I use for the sphere after it's loaded but before I apply it as a texture. I can see problems with both (not even sure if (b) is possible in Three.js yet) - anyone think of a better way or have an opinion? Thanks in advance.