kwin/src/wayland/subsurface_interface_p.h
Vlad Zahorodnii c55de7b70b Emit the committed() signal after the state is applied
Currently, the committed signal is emitted after the client has called
wl_surface.commit. However, this breaks with synchronized subsurfaces.

Notably, Firefox splits a web page in a bunch of smaller layers, which
can be backed by wl_subsurface objects.

All the subsurfaces are in the sync mode. If a layer needs to be
repainted, Firefox will commit the corresponding subsurface with a frame
callback.

Since the committed signal is emitted when the wl_surface.commit request
is invoked, kwin will schedule a new frame immediately. Meaning, that it
is quite likely that firefox will have old contents.

The right thing to do would be to schedule a frame when all the ancestors
of the layer subsurface have been committed.

This change re-jitters the commit logic so the committed signal is
emitted when a new state is applied to the surface. It also slightly
cleans up how SubSurfaceInterface::parentCommit() is called.

It will be nice to cleanup the commit logic further by calling the
surface role's commit hook unconditionally, i.e. not check whether it's
a subsurface. But doing so may result in infinite recursions. How to
clean up that is still TBD.
2021-07-16 13:07:56 +03:00

64 lines
2.2 KiB
C++

/*
SPDX-FileCopyrightText: 2014 Martin Gräßlin <mgraesslin@kde.org>
SPDX-FileCopyrightText: 2020 Vlad Zahorodnii <vlad.zahorodnii@kde.org>
SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
*/
#pragma once
#include "subcompositor_interface.h"
#include "surfacerole_p.h"
#include <QPoint>
#include <QPointer>
#include "qwayland-server-wayland.h"
namespace KWaylandServer
{
class SubCompositorInterfacePrivate : public QtWaylandServer::wl_subcompositor
{
public:
SubCompositorInterfacePrivate(Display *display, SubCompositorInterface *q);
SubCompositorInterface *q;
protected:
void subcompositor_destroy(Resource *resource) override;
void subcompositor_get_subsurface(Resource *resource, uint32_t id,
struct ::wl_resource *surface_resource,
struct ::wl_resource *parent_resource) override;
};
class SubSurfaceInterfacePrivate : public SurfaceRole, public QtWaylandServer::wl_subsurface
{
public:
static SubSurfaceInterfacePrivate *get(SubSurfaceInterface *subsurface);
SubSurfaceInterfacePrivate(SubSurfaceInterface *q, SurfaceInterface *surface,
SurfaceInterface *parent, ::wl_resource *resource);
void commit() override;
void parentCommit();
SubSurfaceInterface *q;
QPoint position = QPoint(0, 0);
QPoint pendingPosition = QPoint(0, 0);
SubSurfaceInterface::Mode mode = SubSurfaceInterface::Mode::Synchronized;
QPointer<SurfaceInterface> surface;
QPointer<SurfaceInterface> parent;
bool hasPendingPosition = false;
protected:
void subsurface_destroy_resource(Resource *resource) override;
void subsurface_destroy(Resource *resource) override;
void subsurface_set_position(Resource *resource, int32_t x, int32_t y) override;
void subsurface_place_above(Resource *resource, struct ::wl_resource *sibling_resource) override;
void subsurface_place_below(Resource *resource, struct ::wl_resource *sibling_resource) override;
void subsurface_set_sync(Resource *resource) override;
void subsurface_set_desync(Resource *resource) override;
};
} // namespace KWaylandServer