[PATCH weston] compositor: fix sub-surface view stacking order

[Kristian Høgsberg]

On Tue, Nov 19, 2013 at 02:03:35PM +0200, ppaalanen at gmail.com wrote:
> From: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
> 
> If you opened a window with sub-surfaces, and then raised another window
> on top of that, the underlaying window's main surface was stacked
> properly, but the sub-surfaces remained on top of the raised window.
> IOW, the raised window was in between the other window and its
> sub-surfaces.

I saw this just the other day when I ran the subsurface test case.
Thanks for the fix Pekka.

Kristian

> This got broken in a7af70436b7dccfacd736626d6719b3e751fd985, "Split the
> geometry information from weston_surface out into weston_view".
> 
> Fix the issues:
> 
> In view_list_add_subsurface_view(), the views need to be added to the
> end of the list, not to the head. This alone fixes the above problem,
> but causes the sub-surface views to be stacked irrespective of their
> surface stacking order. The stacking order in this test case is fixed by
> the changes to view_list_add(), but for sub-sub-surfaces a similar
> change is needed in view_list_add_subsurface_view() too.
> 
> In view_list_add(), build the view list in the sub-surface stacking
> order, instead of pulling the parent surface always on top. Also handle
> the case, when the subsurface_list is completely empty: the parent
> surface's view must still be added.
> 
> Reported-by: Julien Isorce <julien.isorce at collabora.com>
> Signed-off-by: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
> Cc: Jason Ekstrand <jason at jlekstrand.net>
> ---
>  src/compositor.c | 26 ++++++++++++++++++++------
>  1 file changed, 20 insertions(+), 6 deletions(-)
> 
> diff --git a/src/compositor.c b/src/compositor.c
> index b8e0c6e..7c688ef 100644
> --- a/src/compositor.c
> +++ b/src/compositor.c
> @@ -1612,11 +1612,18 @@ view_list_add_subsurface_view(struct weston_compositor *compositor,
>  	}
>  
>  	weston_view_update_transform(view);
> -	wl_list_insert(compositor->view_list.next, &view->link);
>  
> -	wl_list_for_each(child, &sub->surface->subsurface_list, parent_link)
> -		if (child->surface != sub->surface)
> +	if (wl_list_empty(&sub->surface->subsurface_list)) {
> +		wl_list_insert(compositor->view_list.prev, &view->link);
> +		return;
> +	}
> +
> +	wl_list_for_each(child, &sub->surface->subsurface_list, parent_link) {
> +		if (child->surface == sub->surface)
> +			wl_list_insert(compositor->view_list.prev, &view->link);
> +		else
>  			view_list_add_subsurface_view(compositor, child, view);
> +	}
>  }
>  
>  static void
> @@ -1626,11 +1633,18 @@ view_list_add(struct weston_compositor *compositor,
>  	struct weston_subsurface *sub;
>  
>  	weston_view_update_transform(view);
> -	wl_list_insert(compositor->view_list.prev, &view->link);
>  
> -	wl_list_for_each(sub, &view->surface->subsurface_list, parent_link)
> -		if (sub->surface != view->surface)
> +	if (wl_list_empty(&view->surface->subsurface_list)) {
> +		wl_list_insert(compositor->view_list.prev, &view->link);
> +		return;
> +	}
> +
> +	wl_list_for_each(sub, &view->surface->subsurface_list, parent_link) {
> +		if (sub->surface == view->surface)
> +			wl_list_insert(compositor->view_list.prev, &view->link);
> +		else
>  			view_list_add_subsurface_view(compositor, sub, view);
> +	}
>  }
>  
>  static void
> -- 
> 1.8.1.5
>