Avoids a nasty race condition that caused corrupted window decorations

BUG:199735


svn path=/trunk/KDE/kdebase/workspace/; revision=1046461

client.cpp

@@ -449,15 +449,16 @@ void Client::layoutDecorationRects(QRect &left, QRect &top, QRect &right, QRect
                   padding_right + border_right, r.height() - top.height() - bottom.height());
     }
 
+QRegion Client::decorationPendingRegion() const
+    {
+    if (!paintRedirector)
+        return QRegion();
+    return paintRedirector->pendingRegion().translated( x() - padding_left, y() - padding_top );
+    }
+
 void Client::repaintDecorationPending()
     {
-    if ( compositing() )
-        {
-        // The scene will update the decoration pixmaps in the next painting pass
-        const QRegion r = paintRedirector->pendingRegion();
-        Workspace::self()->addRepaint( r.translated( x() - padding_left, y() - padding_top ) );
-        }
-    else
+    if (!compositing())
         ensureDecorationPixmapsPainted();
     }
 

client.h

@@ -336,6 +336,8 @@ class Client
                         QRect(0, 0, width(), height());
         }
 
+        QRegion decorationPendingRegion() const;
+
         enum CoordinateMode {
             DecorationRelative, // Relative to the top left corner of the decoration
             WindowRelative      // Relative to the top left corner of the window

composite.cpp

@@ -414,6 +414,7 @@ void Workspace::performCompositing()
           // TODO I think effects->transformWindowDamage() doesn't need to be called here,
           // pre-paint will extend painted window areas as necessary.
         repaints_region |= c->repaints().translated( c->pos());
+        repaints_region |= c->decorationPendingRegion();        
         c->resetRepaints( c->decorationRect());
         }
     QRegion repaints = repaints_region;

toplevel.h

@@ -66,6 +66,7 @@ class Toplevel
         virtual QSize clientSize() const = 0;
         virtual QRect visibleRect() const; // the area the window occupies on the screen
         virtual QRect decorationRect() const; // rect including the decoration shadows
+        virtual QRegion decorationPendingRegion() const; // decoration region that needs to be repainted
 
         // prefer isXXX() instead
         // 0 for supported types means default for managed/unmanaged types
@@ -251,6 +252,11 @@ inline QRect Toplevel::decorationRect() const
     return rect();
     }
 
+inline QRegion Toplevel::decorationPendingRegion() const
+    {
+    return QRegion();
+    }
+
 inline bool Toplevel::readyForPainting() const
     {
     return ready_for_painting;