I think CAMetalLayer.nextDrawable() shouldn't be very time-consuming, it should be less than 1ms. But occasionally, it will take more than 5ms, just 7ms~13ms, which is a very long time. How can we optimize this? Since this will cause rendering junk.....

When set metalLayer.presentsWithTransaction = true, and we call drawable.present() in bg thread (our rendering thread is not main thread), the app sometimes will crash with: *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Modifications to the layout engine must not be performed from a background thread after it has been accessed from the main thread.' Any solution?

On iOS 18 we can see there is a colorful wave around screen when using siri, I want to implement one in my app. But I tried many ways but not succeed. Any idea?

I'm using AVFoundation to make a multi-track editor app, which can insert multiple track and clip, including scale some clip to change the speed of the clip, (also I'm not sure whether AVFoundation the best choice for me) but after making the scale with scaleTimeRange API, there is some short noise sound in play back. Also, sometimes it's fine when play AVMutableCompostion using AVPlayer with AVPlayerItem, but after exporting with AVAssetReader, will catch some short noise sounds in result file.... Not sure why. Here is the example project, which can build and run directly. https://github.com/luckysmg/daily_images/raw/refs/heads/main/TestDemo.zip