From kde-commits  Wed Sep 24 20:36:12 2008
From: Germain Garand <germain () ebooksfrance ! org>
Date: Wed, 24 Sep 2008 20:36:12 +0000
To: kde-commits
Subject: branches/KDE/4.1/kdelibs/khtml
Message-Id: <1222288572.093602.413.nullmailer () svn ! kde ! org>
X-MARC-Message: https://marc.info/?l=kde-commits&m=122228860711359

SVN commit 864470 by ggarand:

automatically merged revision 864463:
introduce some heavy hacks to avoid QWidget::scroll's performance bug
on unpatched Qt.

BUG: 167739

 M  +102 -1    khtmlview.cpp  


--- branches/KDE/4.1/kdelibs/khtml/khtmlview.cpp #864469:864470
@@ -95,6 +95,7 @@
 //#define DEBUG_FLICKER
 
 //#define DEBUG_PIXEL
+#define FIX_QT_BROKEN_QWIDGET_SCROLL
 
 #include <limits.h>
 #ifdef Q_WS_X11
@@ -243,6 +244,14 @@
         smoothScrolling = false;
         smoothScrollModeIsDefault = true;
         shouldSmoothScroll = false;
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+        oldVScrollUpdatesEnabled = true;
+        oldHScrollUpdatesEnabled = true;
+        oldHScrollOpaquePE = false;
+        oldVScrollOpaquePE = false;
+        brokenQWidgetScroll = false;
+        shouldBeBlitting = false;
+#endif
         complete = false;
         firstLayoutPending = true;
         firstRepaintPending = true;
@@ -314,6 +323,22 @@
         smoothScrolling = true;
         smoothScrollTimer.start(sSmoothScrollTick);
         shouldSmoothScroll = false;
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+        if (view->horizontalScrollBar()->isVisible() && view->verticalScrollBar()->isVisible()) {
+            if (!dx) {
+                oldHScrollOpaquePE = view->horizontalScrollBar()->parentWidget()->testAttribute( Qt::WA_OpaquePaintEvent );
+                view->horizontalScrollBar()->parentWidget()->setAttribute( Qt::WA_OpaquePaintEvent );
+                oldHScrollUpdatesEnabled = view->horizontalScrollBar()->parentWidget()->updatesEnabled();
+                view->horizontalScrollBar()->parentWidget()->setUpdatesEnabled( false );            
+            }
+            if (!dy) {
+                oldVScrollOpaquePE = view->verticalScrollBar()->parentWidget()->testAttribute( Qt::WA_OpaquePaintEvent );
+                view->verticalScrollBar()->parentWidget()->setAttribute( Qt::WA_OpaquePaintEvent );
+                oldVScrollUpdatesEnabled = view->verticalScrollBar()->parentWidget()->updatesEnabled();
+                view->verticalScrollBar()->parentWidget()->setUpdatesEnabled( false );
+            }
+        }
+#endif
     }
 
     void stopScrolling()
@@ -326,6 +351,16 @@
         updateContentsXY();
         smoothScrolling = false;
         shouldSmoothScroll = false;
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+        if (!oldHScrollOpaquePE && view->horizontalScrollBar()->parentWidget()->testAttribute( Qt::WA_OpaquePaintEvent ))
+            view->horizontalScrollBar()->parentWidget()->setAttribute( Qt::WA_OpaquePaintEvent, false );
+        if (!oldVScrollOpaquePE && view->verticalScrollBar()->parentWidget()->testAttribute( Qt::WA_OpaquePaintEvent ))
+            view->verticalScrollBar()->parentWidget()->setAttribute( Qt::WA_OpaquePaintEvent, false );
+        if (!view->horizontalScrollBar()->parentWidget()->updatesEnabled() && oldHScrollUpdatesEnabled)
+            view->horizontalScrollBar()->parentWidget()->setUpdatesEnabled( true );
+        if (!view->verticalScrollBar()->parentWidget()->updatesEnabled() && oldVScrollUpdatesEnabled)
+            view->verticalScrollBar()->parentWidget()->setUpdatesEnabled( true );
+#endif
     }
 
     void updateContentsXY()
@@ -400,6 +435,14 @@
     bool smoothScrolling                          :1;
     bool smoothScrollModeIsDefault                :1;
     bool shouldSmoothScroll                       :1;
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+    bool oldHScrollUpdatesEnabled                 :1;
+    bool oldVScrollUpdatesEnabled                 :1;
+    bool oldHScrollOpaquePE                       :1;
+    bool oldVScrollOpaquePE                       :1;
+    bool brokenQWidgetScroll                      :1;
+    bool shouldBeBlitting                         :1;
+#endif
     bool complete				:1;
     bool firstLayoutPending			:1;
     bool firstRepaintPending                    :1;
@@ -686,6 +729,10 @@
     widget()->resize(w, h);
     if (!widget()->isVisible())
         updateScrollBars();
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+    if (!horizontalScrollBar()->isVisible() || !verticalScrollBar()->isVisible())
+        d->brokenQWidgetScroll = false;
+#endif
 }
 
 int KHTMLView::contentsX() const
@@ -874,6 +921,13 @@
 
     if (!r.isValid() || r.isEmpty()) return;
 
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+    if (d->shouldBeBlitting && r.width() == v.width() && r.height() == v.height()) {
+        d->brokenQWidgetScroll = true;
+    }
+    d->shouldBeBlitting = false;
+#endif
+
     if (d->haveZoom()) {
         p.scale( d->zoomLevel/100., d->zoomLevel/100.);
 
@@ -3852,6 +3906,17 @@
             w = v->widget();
     }
 
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+    bool hideScrollBars = false;
+    if (horizontalScrollBar()->isVisible() && verticalScrollBar()->isVisible()) {
+        if (!d->brokenQWidgetScroll) {
+            d->shouldBeBlitting = true;
+        } else {
+            hideScrollBars = true;
+        }
+    }
+#endif
+
     if ( d->staticWidget ) {
 
         // now remove from view the external widgets that must have completely
@@ -3861,10 +3926,20 @@
 
         if ( d->staticWidget == KHTMLViewPrivate::SBPartial
                                 && m_part->xmlDocImpl() && m_part->xmlDocImpl()->renderer() ) {
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+            if (hideScrollBars) {
+                horizontalScrollBar()->parentWidget()->lower();
+                verticalScrollBar()->parentWidget()->lower();
+            }
+#endif
             // static objects might be selectively repainted, like stones in flowing water
             QRegion r = static_cast<RenderCanvas*>(m_part->xmlDocImpl()->renderer())->staticRegion();
             r.translate( -contentsX(), -contentsY());
             QVector<QRect> ar = r.rects();
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+            if (ar.size() == 1 && ar[0].width() >= visibleWidth() && ar[0].height() >= visibleHeight())
+                d->shouldBeBlitting = false;
+#endif
             for (int i = 0; i < ar.size() ; ++i) {
                 widget()->update( ar[i] );
             }
@@ -3873,19 +3948,45 @@
             for (int i = 0; i < ar.size() ; ++i) {
                 w->scroll( dx, dy, ar[i].translated(off) );
             }
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+           if (hideScrollBars) {
+                horizontalScrollBar()->parentWidget()->raise();
+                verticalScrollBar()->parentWidget()->raise();
+           }
+#endif
             d->scrollExternalWidgets(dx, dy);
-        } else
+        } else {
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+            d->shouldBeBlitting = false;
+#endif
             // we can't avoid a full update
             widget()->update();
+        }
         return;
     }
     if (d->firstRepaintPending)
         return;
+
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+    if (hideScrollBars) {
+        horizontalScrollBar()->parentWidget()->lower();
+        verticalScrollBar()->parentWidget()->lower();
+    }
+#endif
+
     if (m_kwp->isRedirected()) {
         w->scroll(dx, dy, QRect(off.x(), off.y(), visibleWidth(), visibleHeight()));
     }  else {
         widget()->scroll(dx, dy, widget()->rect() & viewport()->rect());
     }
+
+#ifdef FIX_QT_BROKEN_QWIDGET_SCROLL
+    if (hideScrollBars) {
+        horizontalScrollBar()->parentWidget()->raise();
+        verticalScrollBar()->parentWidget()->raise();
+    }
+#endif
+
     d->scrollExternalWidgets(dx, dy);
 }