I'd like to draw an animated (geodesic) polyline in google maps, a bit like this: http://planefinder.net/route/SFO/
I found many tutorials on how to animate a symbol along a polyline, but nothing about animating the polyline itself from the source to the destination.
Any hints ? Where should I start ?
Any help is really appreciated.
I've had some success with the following:
var departure = new google.maps.LatLng(dept_lat, dept_lng); //Set to whatever lat/lng you need for your departure location
var arrival = new google.maps.LatLng(arr_lat, arr_lng); //Set to whatever lat/lng you need for your arrival location
var line = new google.maps.Polyline({
path: [departure, departure],
strokeColor: "#FF0000",
strokeOpacity: 1,
strokeWeight: 1,
geodesic: true, //set to false if you want straight line instead of arc
map: map,
});
var step = 0;
var numSteps = 250; //Change this to set animation resolution
var timePerStep = 5; //Change this to alter animation speed
var interval = setInterval(function() {
step += 1;
if (step > numSteps) {
clearInterval(interval);
} else {
var are_we_there_yet = google.maps.geometry.spherical.interpolate(departure,arrival,step/numSteps);
line.setPath([departure, are_we_there_yet]);
}
}, timePerStep);
This is basically using an interval to redraw the path. At each step, the visible, animated path makes up a larger percentage of the total path from departure to arrival until finally the arrival location is reached.