Platform support: Linux 🐧

[doceazedo]

WRY provides Linux support using WebKitGTK, and a base implementation has already been added to the Godot WRY codebase. However, this implementation does not work at all, because WebKitGTK requires a GTK window, whereas Godot creates its own window.

Possible solutions

I have come down to a few possible solutions:

1. Render the webview in a separate window as an overlay

   • ✅ Can selectively enable/disable inputs on the overlay
   • ⚠️ Only works for windowed and windowed fullscreen games
   • ⚠️ Would require handling input forwarding if interaction with the game needs to continue while the overlay is active
   • 🚨 Recording/sharing the game window would not include the webview (dealbreaker!)
   • 🔗 Overlayed's source code may come in clutch here

2. Render the webview offscreen and use it as a dynamic texture

   • ✅ Common solution for game webviews
   • ✅ Enables embedding webviews inside a 3D world
   • ⚠️ Should be doable, but is not supported out of the box (see Offscreen rendering feature  tauri-apps/wry#391)
   • ⚠️ Requires manual handling of input events
   • 🔗 Bevy Webview implemented this (Linux-only)

3. Bypass Godot’s window creation and provide a custom GTK window with Vulkan context

   • ✅ Would achieve the very same level of support we currently have for the other platforms
   • ✅ Could allow integration of other GTK widgets, not just webviews
     • This is definetly out of the scope of this project, but might lead to a very interesting separate extension
   • ⚠️ Might be very complex to implement
   • 🔗 Reference: Godot Forum Discussion

Next steps

Any further discussions, research, discoveries, or contributions toward implementation are highly appreciated.

[doceazedo]

Linux support is now implemented (#33). Currently only works with X11. Transparency currently does not work. I will now update docs accordingly.

[Squidgical]

Adding this here rather than a new issue as its to do with x11/WebKitGTK;

I get the following error on project startup;

ERROR: Can't open dynamic library: /.../addons/godot_wry/bin/x86_64-unknown-linux-gnu/libgodot_wry.so.
Error: libwebkit2gtk-4.1.so.0: cannot open shared object file: No such file or directory.

I tried installing the lib via sudo apt, which didn't solve the error, then using patchelf to change the link to a copy of the shared object placed in the bin/x86_64-unknown-linux-gnu/ folder, which also didn't work. The error message for that second one is basically the same, but perhaps I've misunderstood how the path is resolved;

ERROR: Can't open dynamic library: /.../addons/godot_wry/bin/x86_64-unknown-linux-gnu/libgodot_wry.so.
Error: ./libwebkit2gtk-4.1.so.0: cannot open shared object file: No such file or directory.

In any case, it leads to;

ERROR: Can't open GDExtension dynamic library: 'res://addons/godot_wry/WRY.gdextension'.
ERROR: Cannot get class 'WebView'.

and the whole extension fails.

This is definitely something going awry with this extension, as I can run tauri apps that use WRY just fine on this computer (even without a global WebKitGTK, as tauri downloads and links it automatically).

System info;

OS: Pop!_OS 22.04 LTS x86_64 
Kernel: 6.12.10-76061203-generic 
Shell: bash 5.1.16 
DE: Unity 
WM: Mutter

$ echo $XDG_SESSION_TYPE
x11

---

Edit:

After some digging, it seems that my distro is doing this cute little thing where they've stopped releasing updates to develop a new DE. I could work around it - tauri must do so - but I'm not interested in staring at .sos all weekend. I'll either use a VM or maybe hop distro (again).

[olivatooo]

Is there any idea when are we going to get transparency? Also somehow related, did people tried to run a game via proton, does the UI work?

[Yukitty]

ah...

godot_core::private::set_gdext_hook::{{closure}}: [panic /home/runner/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/webkit2gtk-2.0.1/src/auto/application_info.rs:21]  GTK has not been initialized. Call `gtk::init` first.
  <C++ Source>  /home/runner/.cargo/git/checkouts/gdext-067f4b88e7bd088f/d4fb159/godot-core/src/private.rs:262 @ godot_core::private::set_gdext_hook::{{closure}}()
godot_core::private::report_call_error: godot-rust function call failed: WebView::ready()
    Reason: GTK has not been initialized. Call `gtk::init` first.
  <C++ Source>  /home/runner/.cargo/git/checkouts/gdext-067f4b88e7bd088f/d4fb159/godot-core/src/private.rs:409 @ godot_core::private::report_call_error()

However, this implementation does not work at all, because WebKitGTK requires a GTK window, whereas Godot creates its own window.

I see. So that's how it is, then...