GMSGroundOverlay animating - should I be using a CATiledLayer?

Question

I am experimenting with the Google Maps for iOS SDK latest version 1.2.1.2944 to animate a GMSGroundOverlay. The user has control over the image sequence, so using an animated UIImage isn't a possibility sadly, so i'm loading in the UIImage on the fly. The GMSGroundOverlay.icon is set to the UIImage that is being updated.

Aside from high memory usage, I seem to have struck a limitation in that whenever I try to overlay a UIImage using GMSGroundOverlay.icon that is more than 1000px x 1000px, it crashes. Referencing a UIImage of 1000px x 1000px gets around the crash.

It strikes me though that maybe I should utilise CATiledLayer for handling the image to only load into memory and subsequently into the icon property of GMSGroundOverlay, but has anyone had any experience of using CATiledLayer with Google Maps for iOS SDK and sequencing images as an animated GMSGroundOverlay?

Answer 1

I got this answer from pressinganswer.com, i think it may helps you.

As currently I cannot use the "position" keypath for animating, I ended up animating it using the "latitude" and "longitude" keypaths separately.

First calculate the points and add them to 2 separate arrays, one for latitude value (y) and one for longitude (x) and then use the values property in CAKeyFrameAnimation to animate. Create 2 CAKeyFrameAnimation objects (1 for each axis) and group them together using CAAnimationGroup and animate them together to form a circle.

In my equation I vary the length of the radius on each axis so that I can also generate an oval path.

NSMutableArray *latitudes = [NSMutableArray arrayWithCapacity:21];
    NSMutableArray *longitudes = [NSMutableArray arrayWithCapacity:21];
    for (int i = 0; i <= 20; i++) {
        CGFloat radians = (float)i * ((2.0f * M_PI) / 20.0f);

        // Calculate the x,y coordinate using the angle
        CGFloat x = hDist * cosf(radians);
        CGFloat y = vDist * sinf(radians);

        // Calculate the real lat and lon using the
        // current lat and lon as center points.
        y = marker.position.latitude + y;
        x = marker.position.longitude + x;


        [longitudes addObject:[NSNumber numberWithFloat:x]];
        [latitudes addObject:[NSNumber numberWithFloat:y]];
    }

    CAKeyframeAnimation *horizontalAnimation = [CAKeyframeAnimation animationWithKeyPath:@"longitude"];
    horizontalAnimation.values = longitudes;
    horizontalAnimation.duration = duration;

    CAKeyframeAnimation *verticleAnimation = [CAKeyframeAnimation animationWithKeyPath:@"latitude"];
    verticleAnimation.values = latitudes;
    verticleAnimation.duration = duration;

    CAAnimationGroup *group = [[CAAnimationGroup alloc] init];
    group.animations = @[horizontalAnimation, verticleAnimation];
    group.duration = duration;
    group.repeatCount = HUGE_VALF;
    [marker.layer addAnimation:group forKey:[NSString stringWithFormat:@"circular-%@",marker.description]];