FreeGLUT windows don't open

[deephack1982]

Hello!

Just experienced this myself on hyprland 0.51, NixOS 25.05 on x86_64.

I was trying to test viture_virtual_display but the software always errors out with

freeglut (./result/bin/v4l2_gl): failed to open display ''

So I reported the issue here

Other case of FreeGLUT not working on Hyprland is reported here
Regards,

[vaxerski]

and why is this a hyprland issue? Just looks like an X app ran under no_xwayland. Does kde work?

[deephack1982]

I don't know if it is a Hyprland issue for sure. This isn't an X app though.

Not sure about KDE but a Wayland Gnome session on the same machine works. I've also tried turning XWayland back on in Hyprland and the app still fails with the same error. viture_virtual_display is a Wayland app as I understand it but I'll see if I can make a minimal freeGLUT app to reproduce what is going on here.

[ItsOhen]

Hate that you made me go look.
It's starting freeglut as x11 for sure.
https://github.com/freeglut/freeglut/blob/3ffa8cb27c47487d2be43b90fce7f888987f0ea9/src/x11/fg_init_x11.c#L172

If it used wl, you would see:
https://github.com/freeglut/freeglut/blob/3ffa8cb27c47487d2be43b90fce7f888987f0ea9/src/wayland/fg_init_wl.c#L78

And the error message would be:
"failed to connect to a Wayland compositor"

[Zebra2711]

try set env GDK_BACKEND=x11

[deephack1982]

I must have misunderstood the docs for this app in that case, apologies. Tried setting GDK_BACKEND but get the same error.

I'm confused then as to why the app works in Gnome and not Hyprland. I'll continue testing and try to figure it out.

[deephack1982]

Okay very embarrassing but while I had the home-manager option xwayland.enable set to true I had somehow slipped xwayland = { enabled = false; }; into my actual settings file template. With this corrected everything works as expected. Very sorry for wasting peoples time.