GMSGroundOverlay animating - should I be using a CATiledLayer?
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
?
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]];