Vehicle movement using bearing

Question

Currently working on vehicle tracking App where I will have to show the movement of the car on the polyline which is set from current location to destination and on the movement of the car I will have have to erase the coordinates like Uber/Ola.

I am facing two problems now i.e.

a>the car is moving perfectly on the polylines but sometimes the car is spinning by itself at few coordinates may be due to the wrong bearing.How can I handle this issue?

b>Not able to understand how can I remove the coordinates that the car has traversed.

I have got this link below to update the polylines while moving but not able to understand where I will put the code to make it work.

update polyline according to the user moving android googleMaps v2

the code I have tried.

https://github.com/avik1990/PolylineUpdater

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {

    private GoogleMap mMap;
    List<LatLng> list_coordianates = new ArrayList();
    PolylineOptions polyLineOptions = null;
    private TimerTask NoticeTimerTask;
    private final Handler handler = new Handler();
    Timer timer = new Timer();
    int index = 0, start_flag = 0;
    boolean forward = false;
    boolean isMarkerRotating;
    Marker mMarker;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);

    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        LatLng sydney = new LatLng(22.573764, 88.359109);
        mMarker = mMap.addMarker(new MarkerOptions().position(sydney).icon(BitmapDescriptorFactory.fromResource(R.drawable.ic_car)).anchor(0.5f, 0.5f));
        mMarker.setAnchor(0.5f, 0.5f);
        mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));
        mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(sydney, 18.0f));
        fillpath();
    }

    ///hardcoded coordinated collected from google map
    private void fillpath() {
        list_coordianates.clear();
        list_coordianates.add(new LatLng(22.573764, 88.359109));
        list_coordianates.add(new LatLng(22.573947, 88.359174));
        list_coordianates.add(new LatLng(22.574145, 88.359244));
        list_coordianates.add(new LatLng(22.574328, 88.359313));
        list_coordianates.add(new LatLng(22.574526, 88.359372));
        list_coordianates.add(new LatLng(22.574720, 88.359469));
        list_coordianates.add(new LatLng(22.574918, 88.359506));
        list_coordianates.add(new LatLng(22.575111, 88.359571));
        list_coordianates.add(new LatLng(22.575299, 88.359624));
        list_coordianates.add(new LatLng(22.575365, 88.359370));
        list_coordianates.add(new LatLng(22.575380, 88.359329));
        list_coordianates.add(new LatLng(22.575390, 88.359276));
        list_coordianates.add(new LatLng(22.575407, 88.359230));
        list_coordianates.add(new LatLng(22.575432, 88.359134));
        list_coordianates.add(new LatLng(22.575457, 88.359083));
        list_coordianates.add(new LatLng(22.575472, 88.359024));
        list_coordianates.add(new LatLng(22.575459, 88.358966));
        list_coordianates.add(new LatLng(22.575511, 88.358903));
        list_coordianates.add(new LatLng(22.575516, 88.358871));
        list_coordianates.add(new LatLng(22.575541, 88.358820));
        list_coordianates.add(new LatLng(22.575546, 88.358755));
        list_coordianates.add(new LatLng(22.575556, 88.358710));
        list_coordianates.add(new LatLng(22.575596, 88.358629));
        list_coordianates.add(new LatLng(22.575620, 88.358576));
        list_coordianates.add(new LatLng(22.575591, 88.358512));
        list_coordianates.add(new LatLng(22.575626, 88.358481));
        list_coordianates.add(new LatLng(22.575634, 88.358443));
        list_coordianates.add(new LatLng(22.575642, 88.358415));
        list_coordianates.add(new LatLng(22.575660, 88.358388));
        list_coordianates.add(new LatLng(22.575663, 88.358355));
        list_coordianates.add(new LatLng(22.575684, 88.358316));
        list_coordianates.add(new LatLng(22.575637, 88.358343));
        list_coordianates.add(new LatLng(22.575613, 88.358355));
        list_coordianates.add(new LatLng(22.575588, 88.358357));
        list_coordianates.add(new LatLng(22.575577, 88.358329));
        list_coordianates.add(new LatLng(22.575551, 88.358336));
        list_coordianates.add(new LatLng(22.575531, 88.358341));
        list_coordianates.add(new LatLng(22.575507, 88.358349));
        list_coordianates.add(new LatLng(22.575480, 88.358355));
        list_coordianates.add(new LatLng(22.575463, 88.358359));
        list_coordianates.add(new LatLng(22.575439, 88.358361));
        list_coordianates.add(new LatLng(22.575422, 88.358363));
        list_coordianates.add(new LatLng(22.575401, 88.358365));
        list_coordianates.add(new LatLng(22.575381, 88.358364));
        list_coordianates.add(new LatLng(22.575367, 88.358352));
        list_coordianates.add(new LatLng(22.575287, 88.358345));
        list_coordianates.add(new LatLng(22.575223, 88.358323));
        list_coordianates.add(new LatLng(22.575144, 88.358323));
        list_coordianates.add(new LatLng(22.575094, 88.358355));
        list_coordianates.add(new LatLng(22.575005, 88.358339));
        list_coordianates.add(new LatLng(22.574881, 88.358414));
        list_coordianates.add(new LatLng(22.574861, 88.358506));
        list_coordianates.add(new LatLng(22.574866, 88.358613));
        list_coordianates.add(new LatLng(22.574836, 88.358677));
        list_coordianates.add(new LatLng(22.574836, 88.358784));
        list_coordianates.add(new LatLng(22.574817, 88.358843));
        list_coordianates.add(new LatLng(22.574827, 88.359010));
        list_coordianates.add(new LatLng(22.574846, 88.359144));
        list_coordianates.add(new LatLng(22.574802, 88.359273));
        list_coordianates.add(new LatLng(22.574802, 88.359337));
        list_coordianates.add(new LatLng(22.574777, 88.359417));
        list_coordianates.add(new LatLng(22.574861, 88.359487));
        list_coordianates.add(new LatLng(22.574945, 88.359535));
        list_coordianates.add(new LatLng(22.575049, 88.359552));
        list_coordianates.add(new LatLng(22.575248, 88.359605));

        ///for drawing the polyline
        drawpolyline();
    }

    private void drawpolyline() {
        polyLineOptions = new PolylineOptions();
        polyLineOptions.addAll(list_coordianates);
        polyLineOptions.width(10);
        polyLineOptions.color(Color.RED);
        mMap.addPolyline(polyLineOptions);

        ///for car movement
        movecaronpath();
    }

    ///used timer to dalay the index
    private void movecaronpath() {
        timer = new Timer();
        NoticeTimerTask = new TimerTask() {

            public void run() {
                handler.post(new Runnable() {

                    public void run() {
                        /////////////////////////////////////////
                        makeAni2(list_coordianates.get(index));
                        /////////////////////////////////////////
                        if (forward) {
                            index++;
                        } else {
                            index--;
                            Log.d("Uber..... ", index + "");
                            if (index < 0) {
                                forward = true;
                                index = 0;
                            }
                        }
                        if (index == list_coordianates.size() && forward) {
                            index--;
                            forward = false;
                        } else {
//                            forward=true;
                        }
                    }
                });
            }
        };
        timer.schedule(NoticeTimerTask, 0, 5000); 
    }

    private void makeAni2(final LatLng latlngg) {
        final LatLng startPosition = mMarker.getPosition();
        final LatLng finalPosition = latlngg;
        final Handler handler = new Handler();
        final long start = SystemClock.uptimeMillis();
        final Interpolator interpolator = new AccelerateDecelerateInterpolator();
        final float durationInMs = 4000;
        final boolean hideMarker = false;

        ///////for rotation of the marker
        rotateMarker(mMarker, startPosition, finalPosition);

        handler.post(new Runnable() {
            long elapsed;
            float t;
            float v;

            @Override
            public void run() {
                // Calculate progress using interpolator
                elapsed = SystemClock.uptimeMillis() - start;
                t = elapsed / durationInMs;

                LatLng currentPosition = new LatLng(
                        startPosition.latitude * (1 - t) + finalPosition.latitude * t,
                        startPosition.longitude * (1 - t) + finalPosition.longitude * t);

                mMarker.setPosition(currentPosition);
                //mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(currentPosition, 18));
                // Repeat till progress is complete.
                if (t < 1) {
                    // Post again 16ms later.
                    handler.postDelayed(this, 16);
                } else {
                    if (hideMarker) {
                        mMarker.setVisible(false);
                    } else {
                        mMarker.setVisible(true);
                    }
                }
            }
        });
    }

    private void rotateMarker(final Marker marker, LatLng startPos, LatLng stopPos) {
        final double toRotation = bearingBetweenLocations(startPos, stopPos);
        DecimalFormat decimalFormat = new DecimalFormat("#");
        System.out.println(decimalFormat.format(toRotation));

        if (!isMarkerRotating) {
            final Handler handler = new Handler();
            final long start = SystemClock.uptimeMillis();
            final float startRotation = marker.getRotation();
            final long duration = 2000;

            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 * (float) 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;
                    }
                }
            });
        }
    }

    ////for calculating of the bearing
    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;
    }

}

score 0 · Answer 1 · answered Apr 09 '18 at 12:42

0

you can get bearing from two Location like below method

public float getBearing(Location begin, Location end) {
    float bearing = 0;
    if (begin != null && end != null) {
        bearing = begin.bearingTo(end);
    }
    AppLog.Log("BEARING", String.valueOf(bearing));

    return bearing;
}

answered Apr 09 '18 at 12:42

KuLdip PaTel

1,069
7
19

no this didn't work.The car stopped rotating now, the vehicle is now dragging. along the polyline – androholic Apr 09 '18 at 12:56

score 0 · Answer 2 · answered Apr 12 '18 at 15:34

a>the car is moving perfectly on the polylines but sometimes the car is spinning by itself at few coordinates may be due to the wrong bearing.How can I handle this issue?

You are probably using MockLocations or some similar mock GPS app to test it, right? Because, at least for Mock Locations, it does that when it is stopped. Try it on a real setting.

b>Not able to understand how can I remove the coordinates that the car has traversed.

Find the point in your list that is the closest to the car's position.
Loop through all the elements on the list up to that closest point and delete them. Just "break" the for loop once you find it. Note that you can't delete elements from a list while you are iterating through its elements. You have to create a new list (something like obsoletePoints) and add them to that list as you iterate through it.
Then simply .removeAll(obsoletePoints) from your original list.

Like so:

for (LatLng currentLatLng : list_coordianate) {
    if (currentLatLng.equals(closestLatLng)) {
        break;
    }
    obsoletePoints.add(currentLatLng);
}
list_coordinate.removeAll(obsoletePoints);

Hope it helps.

Let me know how it worked out or if you have any questions.

Vehicle movement using bearing

2 Answers2