Fix kompmgr in the following ways:

1. Repair spurious crash dialog
2. Make kompmgr start if enabled when Apply is clicked in KCM
3. Fix flickering and general graphical ickiness on desktop switch
4. Fix flickering on root pixmap change


git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdebase@1246518 283d02a7-25f6-0310-bc7c-ecb5cbfe19da

1 files changed, 47 insertions, 21 deletions

diff --git a/kwin/workspace.cpp b/kwin/workspace.cpp
index 16efb606d..acd3387da 100644
--- a/kwin/workspace.cpp
+++ b/kwin/workspace.cpp
@@ -1239,22 +1239,45 @@ bool Workspace::setCurrentDesktop( int new_desktop )
 
         current_desktop = new_desktop; // change the desktop (so that Client::updateVisibility() works)
 
-        for ( ClientList::ConstIterator it = stacking_order.begin(); it != stacking_order.end(); ++it)
-            if ( !(*it)->isOnDesktop( new_desktop ) && (*it) != movingClient )
+        bool desktopHasCompositing = kapp->isCompositionManagerAvailable();	// Technically I should call isX11CompositionAvailable(), but it isn't initialized via my kapp constructir, and in this case it doesn't really matter anyway....
+        if (!desktopHasCompositing) {
+            // If composition is not in use then we can hide the old windows before showing the new ones
+            for ( ClientList::ConstIterator it = stacking_order.begin(); it != stacking_order.end(); ++it) {
+                if ( !(*it)->isOnDesktop( new_desktop ) && (*it) != movingClient )
                 {
-                if( (*it)->isShown( true ) && (*it)->isOnDesktop( old_desktop ))
-                    obs_wins.create( *it );
-                (*it)->updateVisibility();
+                    if( (*it)->isShown( true ) && (*it)->isOnDesktop( old_desktop )) {
+                        obs_wins.create( *it );
+                    }
+                    (*it)->updateVisibility();
                 }
+            }
+        }
 
         rootInfo->setCurrentDesktop( current_desktop ); // now propagate the change, after hiding, before showing
 
         if( movingClient && !movingClient->isOnDesktop( new_desktop ))
             movingClient->setDesktop( new_desktop );
 
-        for ( ClientList::ConstIterator it = stacking_order.fromLast(); it != stacking_order.end(); --it)
-            if ( (*it)->isOnDesktop( new_desktop ) )
+        for ( ClientList::ConstIterator it = stacking_order.fromLast(); it != stacking_order.end(); --it) {
+            if ( (*it)->isOnDesktop( new_desktop ) ) {
                 (*it)->updateVisibility();
+            }
+        }
+
+        if (desktopHasCompositing) {
+            // If composition is in use then we cannot hide the old windows before showing the new ones, 
+            // unless you happen to like the "flicker annoyingly to desktop" effect... :-P
+            XSync( qt_xdisplay(), false);	// Make absolutely certain all new windows are shown before hiding the old ones
+            for ( ClientList::ConstIterator it = stacking_order.begin(); it != stacking_order.end(); ++it) {
+                if ( !(*it)->isOnDesktop( new_desktop ) && (*it) != movingClient )
+                {
+                    if( (*it)->isShown( true ) && (*it)->isOnDesktop( old_desktop )) {
+                        obs_wins.create( *it );
+                    }
+                    (*it)->updateVisibility();
+                }
+            }
+        }
 
         --block_showing_desktop;
         if( showingDesktop()) // do this only after desktop change to avoid flicker
@@ -2547,16 +2570,16 @@ void Workspace::startKompmgr()
     if (!kompmgr || kompmgr->isRunning())
         return;
     if (!kompmgr->start(KProcess::OwnGroup, KProcess::Stderr))
-        {
+    {
         options->useTranslucency = FALSE;
         KProcess proc;
         proc << "kdialog" << "--error"
             << i18n("The Composite Manager could not be started.\\nMake sure you have \"kompmgr\" in a $PATH directory.")
             << "--title" << "Composite Manager Failure";
         proc.start(KProcess::DontCare);
-        }
+    }
     else
-        {
+    {
         delete kompmgr_selection;
         char selection_name[ 100 ];
         sprintf( selection_name, "_NET_WM_CM_S%d", DefaultScreen( qt_xdisplay()));
@@ -2571,8 +2594,8 @@ void Workspace::startKompmgr()
         TQDataStream arg(ba, IO_WriteOnly);
         arg << "";
         kapp->dcopClient()->emitDCOPSignal("default", "kompmgrStarted()", ba);
-        }
-        if (popup){ delete popup; popup = 0L; } // to add/remove opacity slider
+    }
+    if (popup){ delete popup; popup = 0L; } // to add/remove opacity slider
 }
 
 void Workspace::stopKompmgr()
@@ -2604,9 +2627,11 @@ void Workspace::unblockKompmgrRestart()
 void Workspace::restartKompmgr( KProcess *proc )
 // this is for inernal purpose (crashhandling) only, usually you want to use workspace->stopKompmgr(); TQTimer::singleShot(200, workspace, TQT_SLOT(startKompmgr()));
 {
-    if (proc->signalled()) {	// looks like kompmgr crashed
-       if (!allowKompmgrRestart)   // uh oh, it crashed recently already
-            {
+    if (proc->signalled()) {	// looks like kompmgr may have crashed
+      int exit_signal_number = proc->exitSignal();
+      if ( (exit_signal_number == SIGILL) || (exit_signal_number == SIGTRAP) || (exit_signal_number == SIGABRT) || (exit_signal_number == SIGSYS) || (exit_signal_number == SIGFPE) || (exit_signal_number == SIGBUS) || (exit_signal_number == SIGSEGV) ) {
+        if (!allowKompmgrRestart)   // uh oh, it crashed recently already
+        {
             delete kompmgr_selection;
             kompmgr_selection = NULL;
             options->useTranslucency = FALSE;
@@ -2616,8 +2641,9 @@ void Workspace::restartKompmgr( KProcess *proc )
                 << "--title" << i18n("Composite Manager Failure");
             proc.start(KProcess::DontCare);
             return;
-            }
-        if (!kompmgr)
+        }
+      }
+      if (!kompmgr)
             return;
 // this should be useless, i keep it for maybe future need
 //         if (!kcompmgr)
@@ -2628,7 +2654,7 @@ void Workspace::restartKompmgr( KProcess *proc )
 //             }
 // -------------------
         if (!kompmgr->start(KProcess::NotifyOnExit, KProcess::Stderr))
-            {
+        {
             delete kompmgr_selection;
             kompmgr_selection = NULL;
             options->useTranslucency = FALSE;
@@ -2637,12 +2663,12 @@ void Workspace::restartKompmgr( KProcess *proc )
                 << i18n("The Composite Manager could not be started.\\nMake sure you have \"kompmgr\" in a $PATH directory.")
                 << "--title" << i18n("Composite Manager Failure");
             proc.start(KProcess::DontCare);
-            }
+        }
         else
-            {
+        {
             allowKompmgrRestart = FALSE;
             TQTimer::singleShot( 60000, this, TQT_SLOT(unblockKompmgrRestart()) );
-            }
+        }
     }
 }