[Mesa-dev] [PATCH v4 1/2] wayland/egl: initialize window surface size to window size

[Olivier Fourdan]

On Thu, Oct 25, 2018 at 12:05 PM Olivier Fourdan <ofourdan at redhat.com> wrote:
>
> Hi,
>
> On Tue, Aug 7, 2018 at 5:50 PM Juan A. Suarez Romero
> <jasuarez at igalia.com> wrote:
> >
> > When creating a windows surface with eglCreateWindowSurface(), the
> > width and height returned by eglQuerySurface(EGL_{WIDTH,HEIGHT}) is
> > invalid until buffers are updated (like calling glClear()).
> >
> > But according to EGL 1.5 spec, section 3.5.6 ("Surface Attributes"):
> >
> >   "Querying EGL_WIDTH and EGL_HEIGHT returns respectively the width and
> >    height, in pixels, of the surface. For a window or pixmap surface,
> >    these values are initially equal to the width and height of the
> >    native window or pixmap with respect to which the surface was
> >    created"
> >
> > This fixes dEQP-EGL.functional.color_clears.* CTS tests
> >
> > v2:
> > - Do not modify attached_{width,height} (Daniel)
> > - Do not update size on resizing window (Brendan)
> >
> > CC: Daniel Stone <daniel at fooishbar.org>
> > CC: Brendan King <brendan.king at imgtec.com>
> > CC: mesa-stable at lists.freedesktop.org
> > Tested-by: Eric Engestrom <eric at engestrom.ch>
> > ---
> >  src/egl/drivers/dri2/platform_wayland.c | 3 +++
> >  1 file changed, 3 insertions(+)
> >
> > diff --git a/src/egl/drivers/dri2/platform_wayland.c b/src/egl/drivers/dri2/platform_wayland.c
> > index dca099500a8..a5d43094cf3 100644
> > --- a/src/egl/drivers/dri2/platform_wayland.c
> > +++ b/src/egl/drivers/dri2/platform_wayland.c
> > @@ -258,6 +258,9 @@ dri2_wl_create_window_surface(_EGLDriver *drv, _EGLDisplay *disp,
> >        goto cleanup_surf;
> >     }
> >
> > +   dri2_surf->base.Width = window->width;
> > +   dri2_surf->base.Height = window->height;
> > +
> >     visual_idx = dri2_wl_visual_idx_from_config(dri2_dpy, config);
> >     assert(visual_idx != -1);
> >
> > --
> > 2.17.1
>
> Just a quick heads up, this patch is causing a regression with
> "swrast" which does not have DRI2flushExtension.
>
> Easiest way to demonstrate the issue is to use totem with "swrast" on
> mesa-18.2.x (e.g. Fedora 29) under Wayland:
>
>   $ LIBGL_ALWAYS_SOFTWARE=true CLUTTER_BACKEND=gdk totem
>
> Play a video and resize the totem toplevel window, the size of the EGL
> surface remains unchanged...
>
> Reverting that patch fixes the issue, as using a DRI driver which
> supports DRI2flushExtension. Nevertheless, that's a regression.

Sorry, wrong patch, the culprit is:

https://cgit.freedesktop.org/mesa/mesa/commit/src/egl/drivers/dri2/platform_wayland.c?id=a9fb331ea
(or https://cgit.freedesktop.org/mesa/mesa/commit/src/egl/drivers/dri2/platform_wayland.c?id=7af6be886
cherry-picked in 18.2)

And actually reverting just that part from the patch:

@@ -1635,8 +1646,8 @@ swrast_update_buffers(struct dri2_egl_surface *dri2_surf)
if (dri2_surf->back)
return 0;
- if (dri2_surf->base.Width != dri2_surf->wl_win->width ||
- dri2_surf->base.Height != dri2_surf->wl_win->height) {
+ if (dri2_surf->base.Width != dri2_surf->wl_win->attached_width ||
+ dri2_surf->base.Height != dri2_surf->wl_win->attached_height) {
dri2_wl_release_buffers(dri2_surf);

Fixes the issue.

Cheers,
Olivier