XR# —WebXR with .NET, C# & XAML

An SDK to build WebXR-powered 3D, VR & AR apps using .NET, C# & XAML. Created by Userware (@OpenSilverTeam). Powered by @ThreeJS & @AFrameVR. Now in Pre-Alpha.

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

Steady progress on our next-gen UI framework.

Now supports iOS/Android too, and the 3D TextBox is shaping up.

Check out this browser demo powered by #threejs: https://t.co/FHJgHETweV

[XAML.io — Online .NET IDE @xaml_io]

We believe
app development should feel INSTANT.

Meet https://t.co/9enTyWD0I1.
VB6 feel. Built for today.

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

It seems that we've been working on basically the same thing. Our tech XRSharp is a XAML wrapper around Three.js (and it's powered by OpenSilver, which compiles C# to WebAssembly). While currently positioned around XR, it also works on flat displays and could be used as a 3D engine. Maybe we can join forces someday. https://t.co/tx0Q29cTk2

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

@felixturner I just realized that the effect looks similar to the macOS background of the just-announced MacBook Neo:

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

Gorgeous!

[Felix Turner @felixturner]

Gradient pills effect in threejs. Live demo and source below👇 #threejs #webgpu #tsl

[XAML.io — Online .NET IDE @xaml_io]

Big update to https://t.co/9enTyWD0I1 today:
C# IntelliSense/autocomplete is now live.

You can now design, build, and run .NET (C# + XAML) entirely in the browser, with a visual designer and WebAssembly compilation.

No install. No signup.

[OpenSilver - Web-native WPF @OpenSilverTeam]

https://t.co/LyIsIa7PN9

[OpenSilver - Web-native WPF @OpenSilverTeam]

OpenSilver is not an emulator, a wrapper, or an Electron-style bundled browser. It is a complete reimplementation of the WPF/Silverlight API from scratch, using modern .NET, WebAssembly, and the browser's DOM.

On the Web, your C# code compiles to WebAssembly. Unlike canvas-based rendering approaches, XAML is rendered at runtime using real HTML elements: TextBox becomes <textarea>, MediaElement becomes <video>, PasswordBox becomes <input type="password">, Image becomes <img>, and so on. This unlocks native browser behaviors like Ctrl+F search, text selection (to copy text), screen readers, SEO indexing, browser translation, mobile long-press, UI automated testing, and accessibility compliance. The compiled app is a set of static files (WebAssembly, JS, index.html...) that can be hosted anywhere: Azure, AWS, GitHub Pages, or any basic web server. No special server technology is required.

On desktop and mobile (via MAUI-OpenSilver Hybrid or Photino), the UI is still rendered as HTML/CSS, but C# runs as native .NET instead of WebAssembly. This preserves full compatibility with JS libraries and Blazor components (because the UI is still HTML/CSS), while adding native performance and direct access to platform APIs (because the runtime is native .NET).

[OpenSilver - Web-native WPF @OpenSilverTeam]

Blazor components inside XAML. One codebase, six platforms. OpenSilver 3.3 is out.

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

@OpenSilverTeam 🤩

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

photo to 3D model

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

Stunning work.
Would love to see a creative coder try an interactive, real-time @threejs version of this masterpiece.

[Jose_L_Molfino @Jose_Molfino]

Testing mpm solver for mixing color paint strokes
#houdini #mpm

[OpenSilver - Web-native WPF @OpenSilverTeam]

Many people still think OpenSilver is an emulator or wrapper around Silverlight.

It is not.

We did not inherit any Silverlight code. Silverlight was closed source.
We reimplemented the Silverlight/WPF public API from scratch, using modern .NET, WebAssembly, and the browser’s DOM.

Why does this matter to WPF developers?
Because Silverlight was a backward-compatible subset of WPF. Same namespaces, same XAML, same patterns.

This means what began as a Silverlight migration path has naturally evolved into a realistic way to bring WPF-style applications to the web using C#, XAML, and MVVM, without rewriting everything in JavaScript.

And here is what most people do not know:

OpenSilver does not render everything in a canvas. We render XAML using real HTML elements:

• TextBox → <div contenteditable="true">
• MediaElement → <video>
• Hyperlink → <a href>
• WebBrowser control → <iframe>

Why is that a big deal?

Because rendering to the DOM unlocks native browser behaviors:
Ctrl+F, text selection, screen readers, right click on links, SEO, browser translation, copy and paste, mobile long-press, browser extensions, and regulatory accessibility compliance.

You cannot get any of that in a giant canvas rendering model.

This is not just “bringing Silverlight to the web”.
This is bringing WPF-style architecture to the web, in a truly web-native way.

That is why many enterprise teams are migrating, not rewriting.

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

@mrdoob @threejs Nice!

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

I just verified that this other SSGINode example below runs great (and very smoothly) on iOS 18.7.1, even though WebGPU isn’t officially supported on that version: https://t.co/o0gFsQdOYR
Maybe Apple quietly added some support for it. I double-checked that the experimental WebGPU flags are off. Weird…
(BTW, it doesn’t seem to work on Firefox for Windows, where it fails with "this.cNode.getNodeType is not a function")

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

@mxyws @threejs @claudeai I've noticed that this SSGINode demo works properly on iOS 18.7.1 (which, as far as I know, doesn't support WebGPU): https://t.co/Igy4OVGhm3

Is it because SSGINode now supports WebGL as well? Really curious to know. Thanks a lot!

[ycw @ycwhk]

195. sheer wheel 📦 #tsl #threejs
https://t.co/SuugI0dDuF

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

We really want UIs to go in this direction! Check out this amazing interactive real-time app by @reczko_konrad and @cerpow 👏👏👏

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

The new Screen-Space Global Illumination (SSGI) effect in the latest #threejs is out of this world🤯👏. We cannot wait to test it inside XR#

[☄︎ @0xca0a]

going through some models to see the difference that ssr + ssgi makes. it still doesn't seem to handle roughness correctly (or at all), but even in its current form it's pretty amazing. 🥲

sandbox/link below this post ↓

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

@0xca0a omg

[XR# —WebXR with .NET, C# & XAML @xr_sharp]

@jimmy6DOF 🙏

[OpenSilver - Web-native WPF @OpenSilverTeam]

Most browser IDEs fake it: the build actually happens on a remote server.
https://t.co/hS3Vp2sLmD is different: it compiles .NET GUI apps right in your browser via WebAssembly.
No backend at all (except for saving to the cloud or optional AI), which makes it ridiculously scalable.