Bug 145948

SVN commit 669159 by ggarand:

Adapt to Qt 4.3's renewed lack of forgiveness.

It is now mandatory to end any QPainter active on devices 
that are the target of a redirection, which in turn forces the 
unwinding of the stack, making save()/restore() useless.

=> reimplement save/restore for clipping ;(

BUG: 145948



 M  +25 -10    render_layer.cpp  
 M  +2 -0      render_layer.h  
 M  +7 -1      render_replaced.cpp  


--- trunk/KDE/kdelibs/khtml/rendering/render_layer.cpp #669158:669159
@@ -60,11 +60,13 @@
 #include "xml/dom_restyler.h"
 
 #include <QtGui/QStyle>
+#include <QtCore/QStack>
 
 using namespace DOM;
 using namespace khtml;
 
 ScrollBarWidget* RenderLayer::gScrollBar = 0;
+QStack<QRegion>* RenderLayer::s_clipHolder = 0;
 
 #ifndef NDEBUG
 static bool inRenderLayerDetach;
@@ -815,30 +817,37 @@
     paintLayer(this, p, damageRect, selectionOnly);
 }
 
-static void setClip(QPainter* p, const QRect& paintDirtyRect, const QRect& clipRect)
+static void setClip(QPainter* p, const QRect& paintDirtyRect, const QRect& clipRect, bool setup = false)
 {
     if (paintDirtyRect == clipRect)
         return;
-    p->save();
+    if (!RenderLayer::s_clipHolder)
+        RenderLayer::s_clipHolder = new QStack<QRegion>;
 
-#ifdef APPLE_CHANGES
-    p->addClip(clipRect);
-#else
-    p->setClipRect(clipRect, Qt::IntersectClip);
-#endif
-
+    QRegion r = clipRect;
+    if (!RenderLayer::s_clipHolder->isEmpty())
+        r &= RenderLayer::s_clipHolder->top();
+    
+    p->setClipRegion( r );
+    RenderLayer::s_clipHolder->push( r );
 }
 
-static void restoreClip(QPainter* p, const QRect& paintDirtyRect, const QRect& clipRect)
+static void restoreClip(QPainter* p, const QRect& paintDirtyRect, const QRect& clipRect, bool cleanup = false)
 {
     if (paintDirtyRect == clipRect)
         return;
-    p->restore();
+    RenderLayer::s_clipHolder->pop();
+    if (!RenderLayer::s_clipHolder->isEmpty())
+        p->setClipRegion( RenderLayer::s_clipHolder->top() );
+    else
+        p->setClipRegion( QRegion(), Qt::NoClip );
 }
 
 void RenderLayer::paintLayer(RenderLayer* rootLayer, QPainter *p,
                         const QRect& paintDirtyRect, bool selectionOnly)
 {
+    assert( rootLayer != this || !s_clipHolder );
+
     // Calculate the clip rects we should use.
     QRect layerBounds, damageRect, clipRectToApply;
     calculateRects(rootLayer, paintDirtyRect, layerBounds, damageRect, clipRectToApply);
@@ -951,6 +960,12 @@
     // End our transparency layer
     if (isTransparent())
         p->setOpacity(previousOpacity);
+
+    if (s_clipHolder && rootLayer == this) {
+        assert(s_clipHolder->isEmpty());
+        delete s_clipHolder;
+        s_clipHolder = 0;
+    }
 }
 
 bool RenderLayer::nodeAtPoint(RenderObject::NodeInfo& info, int x, int y)
--- trunk/KDE/kdelibs/khtml/rendering/render_layer.h #669158:669159
@@ -51,6 +51,7 @@
 #include "render_object.h"
 
 //template <class T*> class QVector;
+template <class T> class QStack;
 
 namespace khtml {
     class RenderStyle;
@@ -128,6 +129,7 @@
 {
 public:
     static ScrollBarWidget* gScrollBar;
+    static QStack<QRegion>* s_clipHolder;
 
     RenderLayer(RenderObject* object);
     ~RenderLayer();
--- trunk/KDE/kdelibs/khtml/rendering/render_replaced.cpp #669158:669159
@@ -569,11 +569,17 @@
         pp.setCompositionMode(QPainter::CompositionMode_Clear);
         pp.eraseRect(r);
         d = pm;
-    }
+    } else
+        p->end();
+
     QPainter::setRedirected(widget, d, buffered ? QPoint(0,0) : -thePoint);
+
     QPaintEvent e( r );
     QApplication::sendEvent(widget, &e);
     QPainter::restoreRedirected(widget);
+
+    if (!p->isActive())
+        p->begin(p->device());
     p->setWorldMatrix( m );
 
     if (buffered) {

Reopening.
This still happens with today's SVN version.

Cannot reproduce on konqueror 4 (trunk r797319) (qt4.4 rc1)

> Cannot reproduce on konqueror 4 (trunk r797319) (qt4.4 rc1) 
Right, seems to be fixed in the meantime.