QMetaObject crate for Rust VS Azul

You can use Rust with QML[1].

QML is actually pretty amazing. I've been building my block editor[2] view entirely in QML while the model is in C++. This separation of logic and presentation works great. And yes, there are some crashes sometimes (that I find quite easy to debug thanks to the built-in debugger), but take for example a similar app that's built with Rust and Dart[3], in my testing there were still memory leaks that caused my computer to hang. It's better to know you have a bug than for it to be hidden from you.

I agree with parent commenter, saying these cross-platform frameworks will end up supporting the least common denominator set of features. But I found with external open source libraries, the community is catching up very fast. For example, you want the awesome translucency macOS apps have for your Qt app? Here you go[4]. Many such cases. It's also pretty straightforward to add your own custom OS-dependent code, especially so, if someone already open sourced his approach. I recently wanted to move the traffic light buttons on macOS for my app, but couldn't figure the Objective-C code for that. I ended up looking at either Tauri or Electron source code and found my answer.

[1] https://github.com/woboq/qmetaobject-rs

[2] https://www.get-plume.com/

[3] https://www.appflowy.io/

[4] https://github.com/stdware/qwindowkit

I just used qmetaobject-rs and my experience with Qt/QML. There's the QML book from Qt if you're just starting, which is pretty nice https://www.qt.io/product/qt6/qml-book

qmetaobject is probably the most mature Qt Rust binding at the moment. It uses the cpp crate to embed C++ inline in Rust to create its bindings. There are some people using it and it does get some maintenance, but it's not under active development since the original author is now working on Slint.

The bindings currently use the git version of qttypes since I had to merge some upstream changes that are needed for these bindings. So they are not ready for prime time just yet.

There are a bunch of bindings with different language, but even the ones that are officially supported like PySide will still be second class citizen and awkward to use.

Automated binding generation will never give you idiomatic API in whatever language. And if you want an idiomatic library that wraps Qt, it's going to take a huge amount of work.

Which is why I think restricting to QML makes sense because that's a much smaller API surface. That was the ambition behind my previous crate that exposes QML to rust: https://github.com/woboq/qmetaobject-rs/

But now I've moved on to another GUI project: Slint https://github.com/slint-ui/slint

Whisperfish does this with Qt: https://github.com/woboq/qmetaobject-rs/issues/102

What do you want to know? It's pretty easy thanks to the amazing work of guys behind qmetaobject-rs.

This is probably the portion that I found the most difficult. The README of qmetaobject-rs gives us a basic idea of the build script, so I started with that. Here is my starting script

Not sure what you mean but WebRender powers Firefox which definitely works on the desktop.

You can use it to build desktop UI frameworks - see for example https://azul.rs/

I'd been wanting to see this, preferably with JS being optional, and just allowing direct DOM access.

I initially thought this was what Azul was, but it's only just using Servo's WebRender compositor, and rolls its own CSS parser, DOM, and layout engine, so it doesn't benefit from most of the work done on Servo, and supports less CSS features.

https://github.com/fschutt/azul

Both Servo and Fifefox make use of webrender, which is an awesome piece of tech and is well suited to render a web page. Some GUI projects attempted to use webrender directly as well, like Azul and moxie-native

> But no one is saying, "Hey I have a CSS 2.1 compliant rasterizer and compositor that you can use in your C++ or Rust environment!" are they?

There’s actually quite a lot of interesting work going on in that general space, has been in various forms for some years. A couple that immediately spring to mind:

• Azul <https://azul.rs/> builds on WebRender, as used in Firefox. I haven’t looked at it for a few years, but it looks to have grown quite interesting now.

• Blitz <https://github.com/DioxusLabs/blitz> is based on from-scratch implementations of CSS layout and rendering, and wgpu rendering. It’s not usable yet, but is a very interesting concept. If one happens to be familiar with React Native: it’s kinda like that, or React Native Web.

Azul[1] was my solution for that, it was based on WebRender. I didn't get around to finish it in 2019, but I will work on it this year, maybe I'll get it to be mature enough to post it here.

> wide portability (at least Windoze, Linux, MacOS, iOS, Android, embedded: Azul is Windows-Linux-Mac only, don't underestimate the effort to properly port something to a new platform

> "though a Vulkan-based renderer can be made to run pretty much anywhere": WebRender is OpenGL + using software rendering as a fallback

> a permissive open source license: MPL-2.0

> a C interface/wrap to allow a wide programming language binding support: yes

> and an easily extensible and themable set of basic widgets: also yes

[1] https://azul.rs/

There is Iced which is used by system76 in Pop!_OS, Druid [DISCONTINUED], GTK-rs, Relm, Azul and Tauri. Personally I would use Tauri for its speed using the OS's native web render, documentation of use with things such as Sveltekit and the ability to make UI's using JS, CSS and HTML. Tauri similarly to Electron whilst being far faster. But its up to personal preference really. There aren't any solid "go to" options at the moment.

Sounds like you may be interested in azul not exactly servo based but on projects that originate from servo. Also this is not a typical WebView, for example it does not use HTML but uses DOM to define it's UI, and there is no JS engine in there.

Azul uses webrender. But your "glue" program is like half the web browser. You also need a vector graphics library to render websites. Webrender only does boxes, but not complex SVG paths. Once the plan was to use pathfinder, but mozilla fired the dev and they still using an old version of chromium's skia for that.

One day I'll get around to finish my library Azul [1]. Hopefully.

[1] https://azul.rs/

azul