How to convert straight lines to great circles
You can use the ST_Segmentize
PostGIS function to emulate flight routes or great circles.
SELECT ST_Transform(
ST_Segmentize(
the_geom::geography,
10000
)::geometry,
3785
) as the_geom_webmercator,
cartodb_id
FROM table_name
Notice that when any of these routes crosses the dateline, some horizontal lines will appear. To solve this issue, you can check this blog post and apply it’s workaround.