MGLMapView.camera.heading goes negative when rotating to face northwest

[1ec5]

When you rotate an MGLMapView so that it faces anywhere between due north and due west, exclusive, its direction property is wrapped to between 0° and 360°, but its camera’s heading goes negative, indicating an invalid direction according to CLLocationDirection semantics. Therefore, if you then set the camera property of any map view to that MGLMapCamera, you wind up facing the wrong direction.

This regression was introduced in #4790 but was not addressed by df0d118.

/cc @incanus @friedbunny

[1ec5]

-[MGLMapCamera isEqual:] (correctly) accounts for the heading without wrapping, and methods like -[MGLMapView setCamera:withDuration:animationTimingFunction:completionHandler:] bail if the current and new MGLMapCamera objects are identical. Therefore, I believe this regression could be a minor contributing factor to #7236 and #7723.

I say minor because the main code path that would be affected, through -didUpdateLocationSignificantlyAnimated:, would normally require the center coordinate to change significantly. So if there are any redundant calls to this method, this issue would indeed contribute to the problem, but the root cause still lies elsewhere.

[1ec5]

Fixed in #7724 on the release-ios-v3.4.0 branch.