Is it just me who experiences the whole scene freezing in ARKit on iOS 12? It usually happens when you use the app for too long in a space that generates too dense point cloud. After certain amount of time, the whole picture starts to lag and then would stop moving at all, until you cover the camera, or turn it away from your objects, or reset AR session.
Since I have updated to iOS 12, I started to experience this issue, but I searched a few forums to see if someone else got this problem and couldn’t find anyone. I wonder if it’s just me, or is it a common bug?
UPD: iOS 12 beta 2 - the issue still persists
Are you still having the problem? I faced a much worse problem today after upgrading to Xcode10 and iOS 12. I was so crushed when all my ARKit 1.5 projects faced freezing after the first frame was captured from the start.
I managed to solve it by changing project setting, the Deployment Target under General to 12.0. I restarted Xcode just to be sure. All my ARKit projects work now.
I hope this helps, if I find more issues with image recognition freezing on iOS 12 I will mark them here.
来源：https://stackoverflow.com/questions/50891444/arkit-2-freezes-a-bug-or-my-misfortune