OutputManagement fractional scaling

Summary:
In order to have fractional scaling in kwin, we need to communicate it with
kscreen, which means changing the data type in our config protocols.

This introduces a new method on outputdevice and outputconfiguration
to set/request scale as a float.

wl_output is and should remain unchanged as an int

No urgent rush for reviewing/merging this as it's useless without other changes.

Test Plan: Attached unit tests

Reviewers: #kwin, romangg

Subscribers: romangg, zzag, kde-frameworks-devel

Tags: #frameworks

Differential Revision: https://phabricator.kde.org/D13601

src/wayland/autotests/client/test_wayland_outputdevice.cpp

@@ -44,6 +44,7 @@ private Q_SLOTS:
 
     void testRegistry();
     void testModeChanges();
+    void testScaleChange_legacy();
     void testScaleChange();
 
     void testSubPixel_data();
@@ -310,7 +311,7 @@ void TestWaylandOutputDevice::testModeChanges()
     QCOMPARE(output.pixelSize(), QSize(1280, 1024));
 }
 
-void TestWaylandOutputDevice::testScaleChange()
+void TestWaylandOutputDevice::testScaleChange_legacy()
 {
     KWayland::Client::Registry registry;
     QSignalSpy interfacesAnnouncedSpy(&registry, &KWayland::Client::Registry::interfacesAnnounced);
@@ -336,12 +337,51 @@ void TestWaylandOutputDevice::testScaleChange()
     m_serverOutputDevice->setScale(2);
     QVERIFY(outputChanged.wait());
     QCOMPARE(output.scale(), 2);
+    QCOMPARE(output.scaleF(), 2.0); //check we're forward compatiable
+
 
     // change once more
     outputChanged.clear();
     m_serverOutputDevice->setScale(4);
     QVERIFY(outputChanged.wait());
     QCOMPARE(output.scale(), 4);
+    QCOMPARE(output.scaleF(), 4.0);
+}
+
+void TestWaylandOutputDevice::testScaleChange()
+{
+    KWayland::Client::Registry registry;
+    QSignalSpy interfacesAnnouncedSpy(&registry, &KWayland::Client::Registry::interfacesAnnounced);
+    QVERIFY(interfacesAnnouncedSpy.isValid());
+    QSignalSpy announced(&registry, &KWayland::Client::Registry::outputDeviceAnnounced);
+    registry.setEventQueue(m_queue);
+    registry.create(m_connection->display());
+    QVERIFY(registry.isValid());
+    registry.setup();
+    wl_display_flush(m_connection->display());
+    QVERIFY(interfacesAnnouncedSpy.wait());
+
+    KWayland::Client::OutputDevice output;
+    QSignalSpy outputChanged(&output, &KWayland::Client::OutputDevice::done);
+    QVERIFY(outputChanged.isValid());
+    output.setup(registry.bindOutputDevice(announced.first().first().value<quint32>(), announced.first().last().value<quint32>()));
+    wl_display_flush(m_connection->display());
+    QVERIFY(outputChanged.wait());
+    QCOMPARE(output.scaleF(), 1.0);
+
+    // change the scale
+    outputChanged.clear();
+    m_serverOutputDevice->setScaleF(2.2);
+    QVERIFY(outputChanged.wait());
+    QCOMPARE(output.scale(), 2); //check backwards compatibility works
+    QCOMPARE(wl_fixed_from_double(output.scaleF()), wl_fixed_from_double(2.2));
+
+    // change once more
+    outputChanged.clear();
+    m_serverOutputDevice->setScaleF(4.9);
+    QVERIFY(outputChanged.wait());
+    QCOMPARE(output.scale(), 5);
+    QCOMPARE(wl_fixed_from_double(output.scaleF()), wl_fixed_from_double(4.9));
 }
 
 void TestWaylandOutputDevice::testSubPixel_data()

src/wayland/autotests/client/test_wayland_outputmanagement.cpp

@@ -60,6 +60,7 @@ private Q_SLOTS:
     void testFailed();
 
     void testExampleConfig();
+    void testScale();
 
     void testRemoval();
 
@@ -229,7 +230,7 @@ void TestWaylandOutputManagement::applyPendingChanges()
             outputdevice->setGlobalPosition(c->position());
         }
         if (c->scaleChanged()) {
-            outputdevice->setScale(c->scale());
+            outputdevice->setScaleF(c->scaleF());
         }
     }
 }
@@ -472,5 +473,34 @@ void TestWaylandOutputManagement::testExampleConfig()
     QVERIFY(configAppliedSpy.wait(200));
 }
 
+void TestWaylandOutputManagement::testScale()
+{
+    createConfig();
+
+    auto config = m_outputConfiguration;
+    KWayland::Client::OutputDevice *output = m_clientOutputs.first();
+
+    config->setScaleF(output, 2.3);
+    config->apply();
+
+    QSignalSpy configAppliedSpy(config, &OutputConfiguration::applied);
+    m_outputConfigurationInterface->setApplied();
+    QVERIFY(configAppliedSpy.isValid());
+    QVERIFY(configAppliedSpy.wait(200));
+
+    QCOMPARE(output->scale(), 2); //test backwards compatibility
+    QCOMPARE(wl_fixed_from_double(output->scaleF()), wl_fixed_from_double(2.3));
+
+    config->setScale(output, 3);
+    config->apply();
+
+    m_outputConfigurationInterface->setApplied();
+    QVERIFY(configAppliedSpy.isValid());
+    QVERIFY(configAppliedSpy.wait(200));
+
+    QCOMPARE(output->scale(), 3);
+    QCOMPARE(output->scaleF(), 3.0); //test fowards compatibility
+}
+
 QTEST_GUILESS_MAIN(TestWaylandOutputManagement)
 #include "test_wayland_outputmanagement.moc"

src/wayland/server/outputchangeset.cpp

@@ -102,10 +102,16 @@ QPoint OutputChangeSet::position() const
 bool OutputChangeSet::scaleChanged() const
 {
     Q_D();
-    return d->scale != d->o->scale();
+    return !qFuzzyCompare(d->scale, d->o->scaleF());
 }
 
 int OutputChangeSet::scale() const
+{
+    Q_D();
+    return qRound(d->scale);
+}
+
+qreal OutputChangeSet::scaleF() const
 {
     Q_D();
     return d->scale;

src/wayland/server/outputchangeset.h

@@ -78,8 +78,14 @@ public:
     OutputDeviceInterface::Transform transform() const;
     /** The new value for globalPosition. */
     QPoint position() const;
-    /** The new value for scale. */
+    /** The new value for scale.
+     @deprecated see scaleF
+     */
     int scale() const;
+    /** The new value for scale.
+     * @since 5.XX
+     */
+    qreal scaleF() const;
 
 private:
     friend class OutputConfigurationInterface;

src/wayland/server/outputchangeset_p.h

@@ -40,7 +40,7 @@ namespace KWayland
             int modeId;
             OutputDeviceInterface::Transform transform;
             QPoint position;
-            int scale;
+            qreal scale;
         };
     }
 }

src/wayland/server/outputconfiguration_interface.cpp

@@ -55,7 +55,7 @@ public:
     OutputManagementInterface *outputManagement;
     QHash<OutputDeviceInterface*, OutputChangeSet*> changes;
 
-    static const quint32 s_version = 1;
+    static const quint32 s_version = 2;
 
 private:
     static void enableCallback(wl_client *client, wl_resource *resource,
@@ -69,6 +69,8 @@ private:
     static void scaleCallback(wl_client *client, wl_resource *resource,
                               wl_resource * outputdevice, int32_t scale);
     static void applyCallback(wl_client *client, wl_resource *resource);
+    static void scaleFCallback(wl_client *client, wl_resource *resource,
+                              wl_resource * outputdevice, wl_fixed_t scale);
 
     OutputConfigurationInterface *q_func() {
         return reinterpret_cast<OutputConfigurationInterface *>(q);
@@ -83,7 +85,8 @@ const struct org_kde_kwin_outputconfiguration_interface OutputConfigurationInter
     transformCallback,
     positionCallback,
     scaleCallback,
-    applyCallback
+    applyCallback,
+    scaleFCallback
 };
 
 OutputConfigurationInterface::OutputConfigurationInterface(OutputManagementInterface* parent, wl_resource* parentResource): Resource(new Private(this, parent, parentResource))
@@ -185,6 +188,22 @@ void OutputConfigurationInterface::Private::scaleCallback(wl_client *client, wl_
     s->pendingChanges(o)->d_func()->scale = scale;
 }
 
+void OutputConfigurationInterface::Private::scaleFCallback(wl_client *client, wl_resource *resource, wl_resource * outputdevice, wl_fixed_t scale_fixed)
+{
+    Q_UNUSED(client);
+    const qreal scale = wl_fixed_to_double(scale_fixed);
+
+    if (scale <= 0) {
+        qCWarning(KWAYLAND_SERVER) << "Requested to scale output device to" << scale << ", but I can't do that.";
+        return;
+    }
+    OutputDeviceInterface *o = OutputDeviceInterface::get(outputdevice);
+    auto s = cast<Private>(resource);
+    Q_ASSERT(s);
+
+    s->pendingChanges(o)->d_func()->scale = scale;
+}
+
 void OutputConfigurationInterface::Private::applyCallback(wl_client *client, wl_resource *resource)
 {
     Q_UNUSED(client);

src/wayland/server/outputdevice_interface.cpp

@@ -54,7 +54,7 @@ public:
     QPoint globalPosition;
     QString manufacturer = QStringLiteral("org.kde.kwin");
     QString model = QStringLiteral("none");
-    int scale = 1;
+    qreal scale = 1.0;
     SubPixel subPixel = SubPixel::Unknown;
     Transform transform = Transform::Normal;
     QList<Mode> modes;
@@ -80,7 +80,7 @@ private:
     static QVector<Private*> s_privates;
 };
 
-const quint32 OutputDeviceInterface::Private::s_version = 1;
+const quint32 OutputDeviceInterface::Private::s_version = 2;
 
 QVector<OutputDeviceInterface::Private*> OutputDeviceInterface::Private::s_privates;
 
@@ -138,7 +138,7 @@ OutputDeviceInterface::OutputDeviceInterface(Display *display, QObject *parent)
     connect(this, &OutputDeviceInterface::globalPositionChanged, this, [this, d] { d->updateGeometry(); });
     connect(this, &OutputDeviceInterface::modelChanged,          this, [this, d] { d->updateGeometry(); });
     connect(this, &OutputDeviceInterface::manufacturerChanged,   this, [this, d] { d->updateGeometry(); });
-    connect(this, &OutputDeviceInterface::scaleChanged,          this, [this, d] { d->updateScale(); });
+    connect(this, &OutputDeviceInterface::scaleFChanged,          this, [this, d] { d->updateScale(); });
 }
 
 OutputDeviceInterface::~OutputDeviceInterface() = default;
@@ -402,7 +402,11 @@ void OutputDeviceInterface::Private::sendGeometry(wl_resource *resource)
 
 void OutputDeviceInterface::Private::sendScale(const ResourceData &data)
 {
-    org_kde_kwin_outputdevice_send_scale(data.resource, scale);
+    if (wl_resource_get_version(data.resource) < ORG_KDE_KWIN_OUTPUTDEVICE_SCALEF_SINCE_VERSION) {
+        org_kde_kwin_outputdevice_send_scale(data.resource, qRound(scale));
+    } else {
+        org_kde_kwin_outputdevice_send_scalef(data.resource, wl_fixed_from_double(scale));
+    }
 }
 
 void OutputDeviceInterface::Private::sendDone(const ResourceData &data)
@@ -441,12 +445,33 @@ SETTER(setPhysicalSize, const QSize&, physicalSize)
 SETTER(setGlobalPosition, const QPoint&, globalPosition)
 SETTER(setManufacturer, const QString&, manufacturer)
 SETTER(setModel, const QString&, model)
-SETTER(setScale, int, scale)
 SETTER(setSubPixel, SubPixel, subPixel)
 SETTER(setTransform, Transform, transform)
 
 #undef SETTER
 
+void OutputDeviceInterface::setScale(int scale)
+{
+    Q_D();
+    if (d->scale == scale) {
+        return;
+    }
+    d->scale = scale;
+    emit scaleChanged(d->scale);
+    emit scaleFChanged(d->scale);
+}
+
+void OutputDeviceInterface::setScaleF(qreal scale)
+{
+    Q_D();
+    if (qFuzzyCompare(d->scale, scale)) {
+        return;
+    }
+    d->scale = scale;
+    emit scaleChanged(qRound(d->scale));
+    emit scaleFChanged(d->scale);
+}
+
 QSize OutputDeviceInterface::physicalSize() const
 {
     Q_D();
@@ -472,11 +497,18 @@ QString OutputDeviceInterface::model() const
 }
 
 int OutputDeviceInterface::scale() const
+{
+    Q_D();
+    return qRound(d->scale);
+}
+
+qreal OutputDeviceInterface::scaleF() const
 {
     Q_D();
     return d->scale;
 }
 
+
 OutputDeviceInterface::SubPixel OutputDeviceInterface::subPixel() const
 {
     Q_D();

src/wayland/server/outputdevice_interface.h

@@ -53,7 +53,7 @@ class KWAYLANDSERVER_EXPORT OutputDeviceInterface : public Global
     Q_PROPERTY(QString model READ model WRITE setModel NOTIFY modelChanged)
     Q_PROPERTY(QSize pixelSize READ pixelSize NOTIFY pixelSizeChanged)
     Q_PROPERTY(int refreshRate READ refreshRate NOTIFY refreshRateChanged)
-    Q_PROPERTY(int scale READ scale WRITE setScale NOTIFY scaleChanged)
+    Q_PROPERTY(qreal scale READ scaleF WRITE setScaleF NOTIFY scaleFChanged)
     Q_PROPERTY(QByteArray edid READ edid WRITE setEdid NOTIFY edidChanged)
     Q_PROPERTY(OutputDeviceInterface::Enablement enabled READ enabled WRITE setEnabled NOTIFY enabledChanged)
     Q_PROPERTY(QByteArray uuid READ uuid WRITE setUuid NOTIFY uuidChanged)
@@ -100,6 +100,7 @@ public:
     QSize pixelSize() const;
     int refreshRate() const;
     int scale() const;
+    qreal scaleF() const;
     SubPixel subPixel() const;
     Transform transform() const;
     QList<Mode> modes() const;
@@ -114,6 +115,7 @@ public:
     void setManufacturer(const QString &manufacturer);
     void setModel(const QString &model);
     void setScale(int scale);
+    void setScaleF(qreal scale);
     void setSubPixel(SubPixel subPixel);
     void setTransform(Transform transform);
     void addMode(Mode &mode);
@@ -133,7 +135,9 @@ Q_SIGNALS:
     void modelChanged(const QString&);
     void pixelSizeChanged(const QSize&);
     void refreshRateChanged(int);
+    //@deprecated see scaleChanged(real)
     void scaleChanged(int);
+    void scaleFChanged(qreal);
     void subPixelChanged(SubPixel);
     void transformChanged(Transform);
     void modesChanged();

src/wayland/server/outputmanagement_interface.cpp

@@ -57,7 +57,7 @@ private:
     QHash<wl_resource*, OutputConfigurationInterface*> configurationInterfaces;
 };
 
-const quint32 OutputManagementInterface::Private::s_version = 1;
+const quint32 OutputManagementInterface::Private::s_version = 2;
 
 const struct org_kde_kwin_outputmanagement_interface OutputManagementInterface::Private::s_interface = {
     createConfigurationCallback