在面向用户的方向上旋转GMSMarker

Question

我要求在我当前的位置显示一个视图.如果设备旋转或位置将改变它将旋转.我研究很多,但得到所有代码,在某些位置有固定位置或角度但我没有固定位置.任何人都可以朝正确的方向开车.

我还使用了GMSMarker的旋转属性,但它不起作用.

- (void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading
{
    if (newHeading.headingAccuracy < 0){
        NSLog(@"heading accuracy < 0");
        return;
    }

    // Convert Degree to Radian and move the needle
    float oldRad =  (- manager.heading.trueHeading) * M_PI / 180.0f;
    float newRad =  (- newHeading.trueHeading) * M_PI / 180.0f;

    // Compass animation
    CABasicAnimation *theAnimation;
    theAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation"];
    theAnimation.fromValue = [NSNumber numberWithFloat:oldRad];
    theAnimation.toValue   = [NSNumber numberWithFloat:newRad];
    theAnimation.duration  = 0.5f;
    [source.layer addAnimation:theAnimation forKey:@"animateMyRotation"];

//    source.transform =  CGAffineTransformMakeRotation(newRad)
//    GMSMarker *source = [googleMap selectedMarker];
//    source.rotation = newRad;
}

更新:我有旋转方法,但有没有办法旋转GMSMarker,因为没有转换方法.

如何在谷歌地图上旋转他们的车？

Answer 1

我们可以根据课程属性CLLocation Class旋转图像

    let marker:GMSMarker = GMSMarker.init(position: currentLocation!)
    let head = locationManager.location?.course ?? 0
    marker.rotation = head
    marker.icon = UIImage(named: "testyCar.png")
    marker.map = mapView 

Answer 2

你可以做类似的事情 -

-(void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading {

    CLLocationDirection direction = newHeading.trueHeading;
    lastDriverAngleFromNorth = direction;
    self.driverMarker.rotation = lastDriverAngleFromNorth - mapBearing;
}

#pragma mark - GMSMapViewDelegate

- (void)mapView:(GMSMapView *)mapView didChangeCameraPosition:(GMSCameraPosition *)position {

    mapBearing = position.bearing;
    self.driverMarker.rotation = lastDriverAngleFromNorth - mapBearing;
}

Answer 3

当前位置“ CLLocation”对象具有一个称为“ course”的属性

@property(readonly, nonatomic) CLLocationDirection course;

类型为CLLocationDirection（double的typedef），它是位置的角度。

为了使汽车旋转，您需要在后端，方向以及纬度和经度上有额外的字段。通过在UIView上应用变换来使用此信息来旋转汽车

CGAffineTransformMakeRotation(M_PI * (course_of_location) / 180.0);