I recently came across the same use-case. Here is my solution on it.
First, I would like to thank @VipiN for sharing “The Smooth Moving Car Code”. It works smoothly.
The second part is to place car-marker in the right direction and rotate it according to turns. To achieve this I calculated the bearing or heading angle between two successive points(i.e. location updates you receive from device/server). This link will help you understand the maths behind it.
The following code will give you bearing between two locations:
private double bearingBetweenLocations(LatLng latLng1,LatLng latLng2) {
double PI = 3.14159;
double lat1 = latLng1.latitude * PI / 180;
double long1 = latLng1.longitude * PI / 180;
double lat2 = latLng2.latitude * PI / 180;
double long2 = latLng2.longitude * PI / 180;
double dLon = (long2 - long1);
double y = Math.sin(dLon) * Math.cos(lat2);
double x = Math.cos(lat1) * Math.sin(lat2) - Math.sin(lat1)
* Math.cos(lat2) * Math.cos(dLon);
double brng = Math.atan2(y, x);
brng = Math.toDegrees(brng);
brng = (brng + 360) % 360;
return brng;
}
Finally, we need to rotate the car-marker by the angle that we get from above method.
private void rotateMarker(final Marker marker, final float toRotation) {
if(!isMarkerRotating) {
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
final float startRotation = marker.getRotation();
final long duration = 1000;
final Interpolator interpolator = new LinearInterpolator();
handler.post(new Runnable() {
@Override
public void run() {
isMarkerRotating = true;
long elapsed = SystemClock.uptimeMillis() - start;
float t = interpolator.getInterpolation((float) elapsed / duration);
float rot = t * toRotation + (1 - t) * startRotation;
marker.setRotation(-rot > 180 ? rot / 2 : rot);
if (t < 1.0) {
// Post again 16ms later.
handler.postDelayed(this, 16);
} else {
isMarkerRotating = false;
}
}
});
}
}
Cheers!