Annotations and clusters get removed randomly when using MKMapTypeHybridFlyover

[nnhubbard]

I am using MKMapTypeHybridFlyover and am getting my annotations and clusters removed at randomly times leaving a blank map. I can reproduce this using the demo project.

Demo video:

https://youtu.be/y0JfE8FiuXE

This seems to happen when the map is skewed.

Any ideas on what could be going on?

[choefele]

Does this only happen if the map type is MKMapTypeHybrid and you change the camera angle? Or does it happen in other ways as well?

Not sure what's the problem – perhaps you have time to create a PR?

[nnhubbard]

It doesn't seem to happen other mapTypes. I don't know what is wrong either...

[nnhubbard]

I have also gotten this to happen when the map isn't skewed. The really strange thing I am seeing is when turning on debug mode and seeing the blue grids. In other mapTypes the grids move along with the map when you pan it. But, in Flyover mode the grids redraw in strange ways. I leads me to think that the methods for calculation are not taking into account some strange changes that Flyover mode introduces.

Flyover grids example (strange issues): https://youtu.be/K-UxfTABKJM

Hybrid grids example (no issues): https://youtu.be/ZxYls4oV4i4

Any ides on what could be causing this?

[nnhubbard]

Correction to my original bug, I had intended to say that this was happening in MKMapTypeHybridFlyover mode. Flyover seems to be the issue. I had mistakenly just said MKMapTypeHybrid which was incorrect.

[choefele]

About the issue in https://youtu.be/y0JfE8FiuXE – how did you get the camera to show the map at a pitched angle? From the documentation:

If the map type is MKMapTypeSatellite or MKMapTypeHybrid, the pitch value is clamped to 0.

I tried both MKMapTypeSatelliteFlyover and MKMapTypeHybridFlyover and I couldn't get the camera to pitch (neither manually via Option-Shift-Mouse nor via updating the pitch property programatically).

As for the issue in https://youtu.be/K-UxfTABKJM – this seems to be similar to #133. The rect alignment somehow changed on iOS 10 and I don't yet have a way to work around this. I'm happy to accept PRs for this

[nnhubbard]

To get the camera to pitch use a physical device and put two fingers on the screen and slide them up. Make sure to be zoomed in fairly close to earth.

[choefele]

It turns out that pitching only works on a device – not in the simulator.

It looks to me that the problem is related to the pitching angle: the further you pitch, the bigger the size of the rectangles used for clustering until they are huge and the annotations vanish. It appears that map types related to flyover can be pitched further than other map types so that this problem only appears with these types.

At the moment, the only workaround I can offer is to restrict the pitch angles when enabling flyover mode