Google Maps API Direction, out of route

Question

I use the Direction API to plot and save a route between A and B. My application receives a coordinated car gps, I would like to identify if the car is off course previously traced. Anyone have any idea how to do this?

Answer 1

You may create a polyline based on the route and use google.maps.geometry.poly.isLocationOnEdge to check if the current coordinate is placed on/near the polyline.

For an approximate result create the polyline using the overview_path of the route, for higher accuracy use the lat_lngs of the steps of the route