Bug 89712

CVS commit by giessl:

Don't update the tabbar on every(!) MouseMove event but smartly try to
 avoid unnecessary repaints...
...helps a bit, but it is still causing high cpu load, so I'm probably
 going to disable tabbar highlighting as it's IMHO just not worth it.


  M +39 -2     plastik.cpp   1.100
  M +3 -0      plastik.h   1.32


--- kdelibs/kstyles/plastik/plastik.cpp  #1.99:1.100
@@ -3496,15 +3496,52 @@ bool PlastikStyle::eventFilter(QObject *
             QWidget* tabbar = static_cast<QWidget*>(obj);
             hoverWidget = tabbar;
+            hoverTab = 0;
             tabbar->repaint(false);
         }
         else if (ev->type() == QEvent::MouseMove)
         {
-            QWidget* tabbar = static_cast<QWidget*>(obj);
+            QTabBar *tabbar = dynamic_cast<QTabBar*>(obj);
+            QMouseEvent *me = dynamic_cast<QMouseEvent*>(ev);
+
+            if (tabbar && me) {
+                // avoid unnecessary repaints (which otherwise would
 occour on every +                // MouseMove event causing high cpu
 load).
+
+                bool repaint = true;
+
+                // if hoverTab is 0, we can simply skip this...
+                if (hoverTab != 0) {
+                    // go through the tabbar and see which tabs are
 hovered by the mouse. +                    // tabs are overlapping 1
 px, so it's possible that 2 tabs are under the mouse. +               
     int tabCount = 0;
+                    for (int i = 0; i < tabbar->count(); ++i) {
+                        QTab *tab = tabbar->tab(i);
+                        if (tab && tab->rect().contains(me->pos() ) )
 { +                            ++ tabCount;
+
+                            if (tabCount < 2) {
+                                // good, only one tab under the mouse.
+                                if (hoverTab==tab)
+                                    repaint = false; // has been
 updated before, no repaint necessary +                               
 hoverTab = tab;
+                            } else {
+                                // uhh! there's another tab under the
 mouse, repaint... +                                repaint = true;
+                                hoverTab = 0; // make sure the tabbar
 is repainted next time too. +                            }
+
+                        }
+                    }
+                }
+
+                if (repaint)
             tabbar->repaint(false);
         }
+        }
         else if (ev->type() == QEvent::Leave)
         {
             QWidget* tabbar = static_cast<QWidget*>(obj);
             hoverWidget = 0;
+            hoverTab = 0;
             tabbar->repaint(false);
         }

--- kdelibs/kstyles/plastik/plastik.h  #1.31:1.32
@@ -52,4 +52,5 @@

 class QSettings;
+class QTab;

 class PlastikStyle : public KStyle
@@ -289,4 +290,6 @@ private:
     QColor _checkMarkColor;

+    QTab *hoverTab;
+
     // track khtml widgets.
     QMap<const QWidget*,bool> khtmlWidgets;

Uhm, Sandro, you never set hoverTab to a non-zero value.

> Uhm, Sandro, you never set hoverTab to a non-zero value.
Thanks for trying to help. But I think I'm acutally doing: in the line "hoverTab = tab;".

That code never runs. For it to run, hoverTab must already be non-zero, due to the outermost if (hoverTab != 0) conditional. 

Outch, I see... Will be fixed soon.

CVS commit by giessl: 

Ok, this finally reduces the cpu load when hovering Plastik tabs. Thanks maksim!

BUG:89712


  M +0 -3      plastik.cpp   1.103


--- kdelibs/kstyles/plastik/plastik.cpp  #1.102:1.103
@@ -3540,6 +3540,4 @@ bool PlastikStyle::eventFilter(QObject *
                 bool repaint = true;
 
-                // if hoverTab is 0, we can simply skip this...
-                if (hoverTab != 0) {
                     // go through the tabbar and see which tabs are hovered by the mouse.
                     // tabs are overlapping 1 px, so it's possible that 2 tabs are under the mouse.
@@ -3563,5 +3561,4 @@ bool PlastikStyle::eventFilter(QObject *
                         }
                     }
-                }
 
                 if (repaint)