Support saturation/brightness in ThumbnailItem

Two new properties saturation and brightness are added to the
ThumbnailItem which can be set from QML.

The properties are honoured by the Scene when rendering the thumbnail.

scene.cpp

@@ -385,6 +385,8 @@ void Scene::paintWindow(Window* w, int mask, QRegion region, WindowQuadList quad
         EffectWindowImpl *thumb = it.value().data();
         WindowPaintData thumbData(thumb);
         thumbData.setOpacity(data.opacity());
+        thumbData.setBrightness(data.brightness() * item->brightness());
+        thumbData.setSaturation(data.saturation() * item->saturation());
 
         const QRect visualThumbRect(thumb->expandedGeometry());
 

thumbnailitem.cpp

@@ -39,6 +39,8 @@ ThumbnailItem::ThumbnailItem(QDeclarativeItem* parent)
     , m_clip(true)
     , m_parent(QWeakPointer<EffectWindowImpl>())
     , m_parentWindow(0)
+    , m_brightness(1.0)
+    , m_saturation(1.0)
 {
     setFlags(flags() & ~QGraphicsItem::ItemHasNoContents);
     Q_ASSERT(Compositor::isCreated());
@@ -152,4 +154,24 @@ void ThumbnailItem::repaint(KWin::EffectWindow *w)
     }
 }
 
+void ThumbnailItem::setBrightness(qreal brightness)
+{
+    if (qFuzzyCompare(brightness, m_brightness)) {
+        return;
+    }
+    m_brightness = brightness;
+    update();
+    emit brightnessChanged();
+}
+
+void ThumbnailItem::setSaturation(qreal saturation)
+{
+    if (qFuzzyCompare(saturation, m_saturation)) {
+        return;
+    }
+    m_saturation = saturation;
+    update();
+    emit saturationChanged();
+}
+
 } // namespace KWin

thumbnailitem.h

@@ -36,6 +36,8 @@ class ThumbnailItem : public QDeclarativeItem
     Q_PROPERTY(qulonglong wId READ wId WRITE setWId NOTIFY wIdChanged SCRIPTABLE true)
     Q_PROPERTY(bool clip READ isClip WRITE setClip NOTIFY clipChanged SCRIPTABLE true)
     Q_PROPERTY(qulonglong parentWindow READ parentWindow WRITE setParentWindow)
+    Q_PROPERTY(qreal brightness READ brightness WRITE setBrightness NOTIFY brightnessChanged)
+    Q_PROPERTY(qreal saturation READ saturation WRITE setSaturation NOTIFY saturationChanged)
 public:
     explicit ThumbnailItem(QDeclarativeItem *parent = 0);
     virtual ~ThumbnailItem();
@@ -53,9 +55,18 @@ public:
         return m_parentWindow;
     }
     void setParentWindow(qulonglong parentWindow);
+    qreal brightness() const;
+    qreal saturation() const;
+
+public Q_SLOTS:
+    void setBrightness(qreal brightness);
+    void setSaturation(qreal saturation);
+
 Q_SIGNALS:
     void wIdChanged(qulonglong wid);
     void clipChanged(bool clipped);
+    void brightnessChanged();
+    void saturationChanged();
 private Q_SLOTS:
     void init();
     void effectWindowAdded();
@@ -67,8 +78,22 @@ private:
     bool m_clip;
     QWeakPointer<EffectWindowImpl> m_parent;
     qulonglong m_parentWindow;
+    qreal m_brightness;
+    qreal m_saturation;
 };
 
+inline
+qreal ThumbnailItem::brightness() const
+{
+    return m_brightness;
+}
+
+inline
+qreal ThumbnailItem::saturation() const
+{
+    return m_saturation;
+}
+
 } // KWin
 
 #endif // KWIN_THUMBNAILITEM_H