The update steps for the heading indicator are typically small, so animations tend to pile up and cause performance issues. Disabling actions is a slight regression when it comes to large steps (they're not animated now, where they previously were) and this should eventually be addressed.
Also consistently use provided API for disabling CATransaction actions.
* [ios] Don't animate zoom-induced accuracy ring size changes
Improves perceived and actual performance by eliminating the implicit animation that occurred when the accuracy ring changed size during zooms. This previously would pile up animations as the zoom changed, causing an unsightly wobbling effect.
* [ios] Pre-calculate shadow paths for user dot and puck
Performance enhancement suggested by https://developer.apple.com/library/ios/documentation/Cocoa/Conceptual/CoreAnimation_guide/ImprovingAnimationPerformance/ImprovingAnimationPerformance.html
* [ios] Rasterize pulsating inner dot of user location annotation
Supposed performance enhancement and also improves edge smoothness.
A new class, `MGLUserLocationAnnotationView`, has been added that inherits from `MGLAnnotationView`.
Use a subclass of `MGLUserLocationAnnotationView` to customize the appearance of the user location annotation. Use your custom view with the `MGLMapView.userLocation` annotation via the `-mapView:viewForAnnotation:` delegate method.
