damage-regions doesn't show swapped regions from GTK 4 applications
Using Fedora 36 pre-beta with gnome-shell-42~beta-2.fc36.x86_64 I've been trying out the new paint flags (specifically PAINT_DAMAGE_REGION).
With GTK 2 and GTK 3 apps (using Cairo, of course) I get what appears to be the proper damage region displayed. With GTK 4 applications using the Cairo renderer (GSK_RENDERER=cairo
) I also see appropriate regions.
When using GTK 4 with the default OpenGL renderer, every frame shows fully in red. At first I thought it might be because GTK 4 wasn't handling KHR_swap_buffers_with_damage (only the EXT variant which is missing on NVDIA's Wayland EGL driver) but after fixing that, it's the same thing.
Is this just a limitation in the PAINT_DAMAGE_REGION
support or could there be something more sinister at play?