Christian SeligFeb 17, 2023

Reading about @dimillian's issues with SwiftUI and scroll performance in his Ice Cubes app compared to UIKit, and if I were Apple I'd be flying him down to profile his app and see where SwiftUI could be optimized more/what's going on.

Such a great app and showcase of SwiftUI, and even though complex, media-rich timelines with lots of elements can be complex to get right in UIKit, I think instilling community/developer confidence that "Yeah, SwiftUI can do this too" is really important.

Show threadWilliam VabrinskasFeb 17, 2023
@christianselig @dimillian SO I'm also building an app in SwiftUI and scroll performance is definitely an issue. It seems to be related to loading images. I had to scale them all down =(
Show threadThomas RicouardFeb 17, 2023
@wvabrinskas @christianselig we can brainstorm on it, let me know :). I’m at the part where I’m really at the bottom of the barrel. You feel like SwiftUI Image is the bottleneck?
Show threadWilliam VabrinskasFeb 17, 2023
@dimillian @christianselig That's what was hindering my scroll performance. ESPECIALLY if you're loading images from Data. I built a cache to cache the rendered resized image in an NSCache. I look up each image based on an ID and a requested size. I hade to make them like 400px wide, respecting the aspect ration.
Show threadShantara

@wvabrinskas @dimillian @christianselig TIL about NSCache. Somehow I never heard about it before…

After spending half an hour on quickly prototyping a cache for my project, I can already see significant improvements. Thank you!

Feb 17, 2023 at 8:34pmIvory for iOS
Show threadWilliam VabrinskasFeb 17, 2023
@shantara @dimillian @christianselig Glad I could help!