Update README.md

README.md

@@ -145,7 +145,7 @@ widget gallery (`cargo run --example gallery`):
 
 In the long term, I'd like to move [Audulus](http://audulus.com/) over to Rust. After looking at other available UI options, it seemed best to implement something resembling the existing immediate mode UI system I already have working in Audulus, but better.
 
-I had been enjoying the ergonomics of SwiftUI, but SwiftUI simply can't handle big node graphs very well ([we have tried]( https://github.com/audiokit/flow) and had to fall back to manual layout and render with the Canvas node, so we couldn't put custom UI within each node). What you find with SwiftUI (particularly when profiling) is that there's a lot of machinery dealing with the caching aspects of things. It's opaque, scary (crashes on occasion, parts are implemented in C++ not Swift!), and can be rather slow. Often, it seems to be caching things thare are trivial to recompute in the first place.
+I had been enjoying the ergonomics of SwiftUI, but SwiftUI simply can't handle big node graphs very well ([we have tried]( https://github.com/audiokit/flow) and had to fall back to manual layout and render with [Canvas](https://developer.apple.com/documentation/swiftui/canvas), so we couldn't put custom Views within each node). What you find with SwiftUI (particularly when profiling) is that there's a lot of machinery dealing with the caching aspects of things. It's opaque, scary (crashes on occasion, parts are implemented in C++ not Swift!), and can be rather slow. Often, it seems to be caching things thare are trivial to recompute in the first place.
 
 Not so long ago, before programmable shaders, it was necessary to cache parts of a UI in textures (CoreAnimation for example does this) to get good performance. Now we have extremely fast GPUs and such caching is not necessary to achieve good performance. In fact if enough is animating, lots of texture caching can hinder performance, since the caches need to be updated so often. Plus, the textures consume a fair amount of memory, and when you have an unbounded node-graph like Audulus, that memory usage would be unbounded. And what resolution do you pick for those textures?