00:44 <yshui`> hmm, eglgears_wayland ACKs configure event a bit weirdly. it sends ack_configure, then attaches a buffer with the wrong size, then commits.

00:44 <yshui`> the subsequent buffers it attaches are of the right size.

00:45 <yshui`> i think the client sending ack_configure means it understands what the buffer's size have to be? is eglgears' behavior correct?

00:52 <kennylevinsen> It means it acknowledged the configure, not that it cared. It is ultimately the only authority on its own window size, and is free to ignore compositor suggestions. However, reacting on the second commit after ack does seem a little buggy.

00:57 <yshui`> so if the client does care, what the response sequence should be like? `(receives configure event) -> set_window_geometry -> ack -> commit`?

00:58 <yshui`> the clients I've looked at all seems to ack immediately before doing anything else.

01:11 <kennylevinsen> React, then ack, although as compositor suggestions are just that it cannot be strongly enforced.

01:12 <kennylevinsen> That way, compositors can know that the last commit is in acknowledgement and can e.g. perform synchronized tile resizing like sway does

12:03 <wlb> wayland.freedesktop.org/main: José Expósito * libinput 1.22.0 release https://gitlab.freedesktop.org/wayland/wayland.freedesktop.org/commit/b4fe9394d974 libinput/doc/ 1.22.0/.buildinfo 1.22.0/_images/button-debouncing-wave-diagram.svg 1.22.0/_images/button-scrolling.svg 1.22.0/_images/clickfinger-distance.svg 1.22.0/_images/clickfinger.svg 1.22.0/_images/edge-scrolling.svg 1.22.0/_images/gesture-2fg-ambigu

14:45 <yshui`> kennylevinsen: hmm, i see. seems less useful if that can't be enforced.

14:59 <kennylevinsen> ah, sorry - it is actually defined to be ack before commit: https://wayland.app/protocols/xdg-shell#xdg_surface:request:ack_configure

15:00 <kennylevinsen> It does specify "if a client commits in response to a configure, it should...", so the spec does dictate expected behavior here

15:08 <kennylevinsen> So it's valid to file a bug with the client when it does something different, like acking in one commit and reacting in another. But the client is allowed to resize itself at will, so we can't really enforce a certain size...

20:06 <DemiMarie> kennylevinsen: what about e.g. tiling compositors that need to force a certain window size?

20:14 <kennylevinsen> DemiMarie: the xdg_toplevel state "maximized" says that a client must obey the configured dimension

20:16 <kennylevinsen> but sway implements clipping of tiling containers in case the client renders too big, and centering in case it is too small

20:22 <kennylevinsen> (clipping happens when a container dimension shrinks past the clients minimum render size, which is sometimes surprisingly large)