ShowPaint effect supports QPainter Compositing

effects/showpaint/showpaint.cpp

@@ -31,6 +31,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <math.h>
 
 #include <qcolor.h>
+#include <QPainter>
 
 namespace KWin
 {
@@ -60,6 +61,9 @@ void ShowPaintEffect::paintScreen(int mask, QRegion region, ScreenPaintData& dat
     if (effects->compositingType() == XRenderCompositing)
         paintXrender();
 #endif
+    if (effects->compositingType() == QPainterCompositing) {
+        paintQPainter();
+    }
     if (++color_index == sizeof(colors) / sizeof(colors[ 0 ]))
         color_index = 0;
 }
@@ -115,4 +119,13 @@ void ShowPaintEffect::paintXrender()
 #endif
 }
 
+void ShowPaintEffect::paintQPainter()
+{
+    QColor color = colors[ color_index ];
+    color.setAlphaF(0.2);
+    foreach (const QRect & r, painted.rects()) {
+        effects->scenePainter()->fillRect(r, color);
+    }
+}
+
 } // namespace

effects/showpaint/showpaint.h

@@ -37,6 +37,7 @@ public:
 private:
     void paintGL();
     void paintXrender();
+    void paintQPainter();
     QRegion painted; // what's painted in one pass
     int color_index;
 };