On: Rust 2021: GUI

[int_19h]

Define "all the way through"? I mean, on Windows, for example, you're always going to have some C or C++ code from Win32 DLLs on the stack in any GUI app, because you'll need a top-level window even if you're rendering everything else yourself, and it will have a Win32 message loop etc. But if that's acceptable, what's wrong with using the system libraries for text rendering, or even complete widgets?

[shmerl → int_19h]

Since it's a UI library, I'd say deep enough to take care of the actual UI. Whether it depends on system libc and the like is less about that.

I.e. imagine being able to use this library on something like RedoxOS, not just on Linux. That would fit the idea.

[int_19h → shmerl]

But what constitutes "actual UI"? You have to link to way more than system libc to make a GUI app on Windows.

And it's kinda orthogonal to using it on OSes that don't have their own UI layer, because that can be implemented as another backend. For example, wxWidgets wraps native widgets on Win32/macOS/X11 (with Gtk considered "native" for the latter) - but it also has wxUniversal, that renders by itself, and is the backend normally used on platforms like DirectFB.