Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
Animating Markers
/* Copyright 2013 Google Inc.
Licensed under Apache 2.0: http://www.apache.org/licenses/LICENSE-2.0.html */
package com.example.latlnginterpolation;
import android.animation.ObjectAnimator;
import android.animation.TypeEvaluator;
import android.animation.ValueAnimator;
import android.annotation.TargetApi;
import android.os.Build;
import android.os.Handler;
import android.os.SystemClock;
import android.util.Property;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.view.animation.Interpolator;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
public class MarkerAnimation {
static void animateMarkerToGB(final Marker marker, final LatLng finalPosition, final LatLngInterpolator latLngInterpolator) {
final LatLng startPosition = marker.getPosition();
final Handler handler = new Handler();
final long start = SystemClock.uptimeMillis();
final Interpolator interpolator = new AccelerateDecelerateInterpolator();
final float durationInMs = 3000;
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;
v = interpolator.getInterpolation(t);
marker.setPosition(latLngInterpolator.interpolate(v, startPosition, finalPosition));
// Repeat till progress is complete.
if (t < 1) {
// Post again 16ms later.
handler.postDelayed(this, 16);
}
}
});
}
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
static void animateMarkerToHC(final Marker marker, final LatLng finalPosition, final LatLngInterpolator latLngInterpolator) {
final LatLng startPosition = marker.getPosition();
ValueAnimator valueAnimator = new ValueAnimator();
valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
float v = animation.getAnimatedFraction();
LatLng newPosition = latLngInterpolator.interpolate(v, startPosition, finalPosition);
marker.setPosition(newPosition);
}
});
valueAnimator.setFloatValues(0, 1); // Ignored.
valueAnimator.setDuration(3000);
valueAnimator.start();
}
@TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
static void animateMarkerToICS(Marker marker, LatLng finalPosition, final LatLngInterpolator latLngInterpolator) {
TypeEvaluator<LatLng> typeEvaluator = new TypeEvaluator<LatLng>() {
@Override
public LatLng evaluate(float fraction, LatLng startValue, LatLng endValue) {
return latLngInterpolator.interpolate(fraction, startValue, endValue);
}
};
Property<Marker, LatLng> property = Property.of(Marker.class, LatLng.class, "position");
ObjectAnimator animator = ObjectAnimator.ofObject(marker, property, typeEvaluator, finalPosition);
animator.setDuration(3000);
animator.start();
}
}
/* Copyright 2013 Google Inc.
Licensed under Apache 2.0: http://www.apache.org/licenses/LICENSE-2.0.html */
package com.example.latlnginterpolation;
import com.google.android.gms.maps.model.LatLng;
import static java.lang.Math.asin;
import static java.lang.Math.atan2;
import static java.lang.Math.cos;
import static java.lang.Math.pow;
import static java.lang.Math.sin;
import static java.lang.Math.sqrt;
import static java.lang.Math.toDegrees;
import static java.lang.Math.toRadians;
public interface LatLngInterpolator {
public LatLng interpolate(float fraction, LatLng a, LatLng b);
public class Linear implements LatLngInterpolator {
@Override
public LatLng interpolate(float fraction, LatLng a, LatLng b) {
double lat = (b.latitude - a.latitude) * fraction + a.latitude;
double lng = (b.longitude - a.longitude) * fraction + a.longitude;
return new LatLng(lat, lng);
}
}
public class LinearFixed implements LatLngInterpolator {
@Override
public LatLng interpolate(float fraction, LatLng a, LatLng b) {
double lat = (b.latitude - a.latitude) * fraction + a.latitude;
double lngDelta = b.longitude - a.longitude;
// Take the shortest path across the 180th meridian.
if (Math.abs(lngDelta) > 180) {
lngDelta -= Math.signum(lngDelta) * 360;
}
double lng = lngDelta * fraction + a.longitude;
return new LatLng(lat, lng);
}
}
public class Spherical implements LatLngInterpolator {
/* From github.com/googlemaps/android-maps-utils */
@Override
public LatLng interpolate(float fraction, LatLng from, LatLng to) {
// http://en.wikipedia.org/wiki/Slerp
double fromLat = toRadians(from.latitude);
double fromLng = toRadians(from.longitude);
double toLat = toRadians(to.latitude);
double toLng = toRadians(to.longitude);
double cosFromLat = cos(fromLat);
double cosToLat = cos(toLat);
// Computes Spherical interpolation coefficients.
double angle = computeAngleBetween(fromLat, fromLng, toLat, toLng);
double sinAngle = sin(angle);
if (sinAngle < 1E-6) {
return from;
}
double a = sin((1 - fraction) * angle) / sinAngle;
double b = sin(fraction * angle) / sinAngle;
// Converts from polar to vector and interpolate.
double x = a * cosFromLat * cos(fromLng) + b * cosToLat * cos(toLng);
double y = a * cosFromLat * sin(fromLng) + b * cosToLat * sin(toLng);
double z = a * sin(fromLat) + b * sin(toLat);
// Converts interpolated vector back to polar.
double lat = atan2(z, sqrt(x * x + y * y));
double lng = atan2(y, x);
return new LatLng(toDegrees(lat), toDegrees(lng));
}
private double computeAngleBetween(double fromLat, double fromLng, double toLat, double toLng) {
// Haversine's formula
double dLat = fromLat - toLat;
double dLng = fromLng - toLng;
return 2 * asin(sqrt(pow(sin(dLat / 2), 2) +
cos(fromLat) * cos(toLat) * pow(sin(dLng / 2), 2)));
}
}
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment