[julik]

The animations were there, but they were frame-based with the number of frames carefully calculated to show UI state changes that were relevant. For example, when you would open a folder, there would be an animation showing a window rect animating from the folder icon into the window shape, but it would be very subtle - I remember it being 1 or 2 intermediate frames at most. It was enough to show how you get from "there" to "here" but not dizziingly egregious the way it became in Aqua.

Truth be told, I do have a suspicion that some folks (possibly - some folks close to Avie or other former NeXT seniors post-acquisition) have noticed that with dynamic loading, hard drive speed, and ubiquitous dynamic dispatch of ObjC OSX would just be extremely, extremely slow. So they probably conjured a scheme to show fancy animations to people and wooing everyone with visual effects to conceal that a bit. Looney town theory, I know, but I do wonder. Rhapsody was also perceptually very slow, and probably not for animations.

There were also quite a few tricks used all the way from the dithering/blitting optimizations on the early Macs. For example, if you can blit a dotted rect for a window being dragged instead of buffering the entire window, everything underneath, the shadow mask - and then doing the shadow compositing and the window compositing on every redraw - you can save a ton of cycles.

You could very well have do-wait-do-wait loops when custom text compositing or layout was involved and not thoroughly optimized - like in early versions of InDesign, for instance - but it was the exception rather than the rule.

[mosura]

> Truth be told, I do have a suspicion that some folks (possibly - some folks close to Avie or other former NeXT seniors post-acquisition) have noticed that with dynamic loading, hard drive speed, and ubiquitous dynamic dispatch of ObjC OSX would just be extremely, extremely slow. So they probably conjured a scheme to show fancy animations to people and wooing everyone with visual effects to conceal that a bit. Looney town theory, I know, but I do wonder. Rhapsody was also perceptually very slow, and probably not for animations.

Done exactly this myself to conceal ugly inconsistent lags - I don’t think it is that uncommon an idea.

[prewett]

I'm think that ObjC's dynamic dispatch is reasonably fast. I remember reading something about being able to do millions of dynamic dispatch calls per second (so less 1 us per) a long time ago (2018-ish?), but I can't think how to find it. The best I could come up with is [1], which benchmarks it as 2.8 times faster than a Python call, and something like 20% slower than Swift's static calling. In the Aqua time-frame I think that it would not have been slow enough to need animations to cover for it.

[1] https://forums.swift.org/t/performance-of-swift/26911