> The Factor UI is a GUI toolkit together with a set of developer tools, written entirely in Factor, implemented on top of a combination of OpenGL and native platform APIs: X11, Win32 and Cocoa.
> UI gadgets are rendered using the cross-platform OpenGL API, while native platform APIs are used to create windows and receive events. The platform bindings can be also used independently; X11 binding has also been used in a Factor window manager, Factory, which is no longer maintained. The Cocoa binding is used directly by the webkit-demo vocabulary in Factor.
Fascinating. Probably dead and no mention of Wayland, but fascinating.
The cross-platform UI that Factor has works on macOS, Windows, and Linux. On Linux, it unfortunately still uses a GTK2-GLext project for the OpenGL widget that we render into, but modern GTK3/4 has a Gtk.GlArea that we need to switch to using which will improve the compatibility on Wayland. However, it works fine with even the latest Ubuntu 25.10 release.
And of course, you could use other libraries easily, such as Raylib:
https://concatenative.org/wiki/view/Factor/UI
> The Factor UI is a GUI toolkit together with a set of developer tools, written entirely in Factor, implemented on top of a combination of OpenGL and native platform APIs: X11, Win32 and Cocoa.
> UI gadgets are rendered using the cross-platform OpenGL API, while native platform APIs are used to create windows and receive events. The platform bindings can be also used independently; X11 binding has also been used in a Factor window manager, Factory, which is no longer maintained. The Cocoa binding is used directly by the webkit-demo vocabulary in Factor.
Fascinating. Probably dead and no mention of Wayland, but fascinating.