Ribir VS rui

Given the rather bad (still!) error messages you get with SwiftUI that seem to be a result of function builders, I'd say it wasn't worth it. At least I get fewer of the "couldn't produce a diagnostic, please file a bug" errors than I used to.

Then there are property wrappers, which wrap struct/class fields with get/set code (IIRC Lattner didn't like the property wrappers). They've been partially replaced in SwiftUI by macros. The @Observable macro (probably the most widely used one) decorates your class with code that notifies listeners (almost always SwiftUI) of changes. I'd be curious to see what SwiftUI would look like without property wrappers (or macros).

I think they had a missed opportunity to really add robust updating of views in response state changes. Currently it's still relatively easy to not have your SwiftUI views update because your data model uses some object that isn't @Observable.

I wrote a UI library inspired by SwiftUI, but in Rust [1], and of course I couldn't add anything to the language, and more experienced Rust programmers discouraged me from using macros. So it can be done without all the extra stuff Swift added.

[1] https://github.com/audulus/rui

Inspired by Xilem, Leptos and rui, Floem aims to be a high performance declarative UI library with minimal effort from the user.

My rui library can render UIs at 120fps, uses similar SDF techniques (though uses a single shader for all rendering): https://github.com/audulus/rui

Is their GPUI library open source?

I think the jury is still out on whether rust is good or bad for UI. Once rust UI libraries are more mature we'll get a sense of it. There are some advantages of static typing, even for UI (see SwiftUI for example). I'll grant the pickiness of rust can be a challenge. Anyway give us some time to work on stuff.

Here's my effort: https://github.com/audulus/rui

rui

Depending on the scale of your project, I could suggest rui library which is cross platform though it's not related to gtk, https://github.com/audulus/rui, It's inspired by swiftUI

I've done a library for vector graphics on the GPU which works pretty well for my uses:

https://github.com/audulus/vger

and a rust version:

https://github.com/audulus/vger-rs

(which powers my rust GUI library: https://github.com/audulus/rui)

Here's the approach for rendering path fills. From the readme:

> The bezier path fill case is somewhat original. To avoid having to solve quadratic equations (which has numerical issues), the fragment function uses a sort-of reverse Loop-Blinn. To determine if a point is inside or outside, vger tests against the lines formed between the endpoints of each bezier curve, flipping inside/outside for each intersection with a +x ray from the point. Then vger tests the point against the area between the bezier segment and the line, flipping inside/outside again if inside. This avoids the pre-computation of Loop-Blinn, and the AA issues of Kokojima.

It works pretty well, and doesn't require as much preprocessing as the code in the article. Also doesn't require any GPU compute (though I do use GPU compute for some things). I think ultimately the approach in the article (essentially Piet-metal, aka tessellating and binning into tiles) will deliver better performance, and support more primitives, but at greater implementation complexity. I've tried the Piet-metal approach myself and it's tricky! I like the simpler Shadertoy/SDF inspired approach :)

You should look into rui, https://github.com/audulus/rui It is an amazing ui Library for rust