kdesktop: better support for old-school multihead setupsFat-Zer/fix/kdesktop-multihead

This fixes several issues on "old-school multihead" X11 setups (with
several screens per display i.e. when DISPLAY has form ":x.y"
also known as "TDE_MULTIHEAD" or "Zaphode mode"). Also it slightly
enhances functionality for more common xinerama setups. In particular:
* fixed an issue where on primary screen wallpaper is getting rendered
  for both secondary and primary on certain kdesktop configurations.
* fixed an issue on walpaper config dialog where previews for two
  monitors were displayed overlapped.
* update preview in config dialog in case a monitor gets
  connected/disconnected.
* some minor whitespace cleanup.

1 files changed, 53 insertions, 31 deletions

diff --git a/kcontrol/background/bgmonitor.cpp b/kcontrol/background/bgmonitor.cpp
index ac826a1ff..75fd56546 100644
--- a/kcontrol/background/bgmonitor.cpp
+++ b/kcontrol/background/bgmonitor.cpp
@@ -5,16 +5,16 @@
    Copyright (C) 2002 Laurent Montel <montell@club-internet.fr>
    Copyright (C) 2003 Waldo Bastian <bastian@kde.org>
    Copyright (C) 2005 David Saxton <david@bluehaze.org>
-  
+
    This program is free software; you can redistribute it and/or
-   modify it under the terms of the GNU General Public License 
+   modify it under the terms of the GNU General Public License
    version 2 as published by the Free Software Foundation.
-   
+
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
-   
+
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
@@ -30,6 +30,8 @@
 #include <tqpixmap.h>
 #include <tqwhatsthis.h>
 
+#include <memory>
+
 #include "bgmonitor.h"
 
 // Constants used (should they be placed somewhere?)
@@ -40,16 +42,10 @@
 BGMonitorArrangement::BGMonitorArrangement(TQWidget *parent, const char *name)
     : TQWidget(parent, name)
 {
-    m_pBGMonitor.resize( TQApplication::desktop()->numScreens(), 0l );
-    
-    for (int screen = 0; screen < TQApplication::desktop()->numScreens(); ++screen)
-    {
-        BGMonitorLabel * label = new BGMonitorLabel(this);
-        m_pBGMonitor[screen] = label;
-        
-        connect( label->monitor(), TQ_SIGNAL(imageDropped(const TQString &)), this, TQ_SIGNAL(imageDropped(const TQString &)) );
-    }
-    
+    connect(TQApplication::desktop(), TQ_SIGNAL(screenCountChanged(int)),
+            this ,                    TQ_SLOT(updateArrangement()));
+    connect(TQApplication::desktop(), TQ_SIGNAL(resized(int)),
+            this ,                    TQ_SLOT(updateArrangement()));
     parent->setFixedSize(200, 186);
     setFixedSize(200, 186);
     updateArrangement();
@@ -92,40 +88,66 @@ void BGMonitorArrangement::updateArrangement()
     // value. The expanded value is used for setting the size of the monitor
     // image that contains the preview of the background. The monitor image
     // will set the background preview back to the normal value.
-    
+
+    bool isVDesktop = TQApplication::desktop()->isVirtualDesktop();
     TQRect overallGeometry;
-    for (int screen = 0; screen < TQApplication::desktop()->numScreens(); ++screen)
-        overallGeometry |= TQApplication::desktop()->screenGeometry(screen);
-    
+    size_t screen_num = isVDesktop ? TQApplication::desktop()->numScreens() : 1;
+
+    // create/destroy monitors
+    if (m_pBGMonitor.size() != screen_num) {
+        size_t old_size = m_pBGMonitor.size();
+        if(old_size<screen_num) {
+            for (size_t screen = old_size; screen < screen_num; ++screen)
+            {
+                m_pBGMonitor.emplace_back(std::make_unique<BGMonitorLabel>(this));
+                connect( m_pBGMonitor[screen]->monitor(), TQ_SIGNAL(imageDropped(const TQString &)), this, TQ_SIGNAL(imageDropped(const TQString &)) );
+            }
+        } else {
+            m_pBGMonitor.resize(screen_num);
+        }
+    }
+        overallGeometry = TQApplication::desktop()->screenGeometry();
+    if (isVDesktop) {
+        for (size_t screen = 0; screen < screen_num; ++screen)
+            overallGeometry |= TQApplication::desktop()->screenGeometry(screen);
+    } else {
+        overallGeometry = TQApplication::desktop()->screenGeometry();
+    }
+
     TQRect expandedOverallGeometry = expandToPreview(overallGeometry);
-    
+
     double scale = TQMIN(
                 double(width()) / double(expandedOverallGeometry.width()),
                 double(height()) / double(expandedOverallGeometry.height())
                        );
-    
+
     m_combinedPreviewSize = overallGeometry.size() * scale;
-    
+
     m_maxPreviewSize = TQSize(0,0);
     int previousMax = 0;
-    
-    for (int screen = 0; screen < TQApplication::desktop()->numScreens(); ++screen)
-    {
+
+    auto screenSetupWorker = [&](size_t screen){
         TQPoint topLeft = (TQApplication::desktop()->screenGeometry(screen).topLeft() - overallGeometry.topLeft()) * scale;
-        TQPoint expandedTopLeft = expandToPreview(topLeft);
-        
         TQSize previewSize = TQApplication::desktop()->screenGeometry(screen).size() * scale;
+
+        TQPoint expandedTopLeft = expandToPreview(topLeft);
         TQSize expandedPreviewSize = expandToPreview(previewSize);
-        
+
         if ( (previewSize.width() * previewSize.height()) > previousMax )
         {
             previousMax = previewSize.width() * previewSize.height();
             m_maxPreviewSize = previewSize;
         }
-        
+
         m_pBGMonitor[screen]->setPreviewPosition( TQRect( topLeft, previewSize ) );
         m_pBGMonitor[screen]->setGeometry( TQRect( expandedTopLeft, expandedPreviewSize ) );
         m_pBGMonitor[screen]->updateMonitorGeometry();
+    };
+    if(isVDesktop) {
+        for (size_t screen = 0; screen < screen_num; ++screen)
+            screenSetupWorker(screen);
+    } else {
+        screenSetupWorker(TQApplication::desktop()->primaryScreen());
     }
 }
 
@@ -142,7 +164,7 @@ void BGMonitorArrangement::setPixmap( const KPixmap & pm )
     for (unsigned screen = 0; screen < m_pBGMonitor.size(); ++screen)
     {
         TQRect position = m_pBGMonitor[screen]->previewPosition();
-        
+
         TQPixmap monitorPixmap( position.size(), pm.depth() );
         copyBlt( &monitorPixmap, 0, 0, &pm, position.x(), position.y(), position.width(), position.height() );
         m_pBGMonitor[screen]->monitor()->setPixmap(monitorPixmap);
@@ -160,7 +182,7 @@ BGMonitorLabel::BGMonitorLabel(TQWidget *parent, const char *name)
     setScaledContents(true);
     setPixmap( TQPixmap( locate("data",  "kcontrol/pics/monitor.png") ) );
     m_pBGMonitor = new BGMonitor(this);
-    
+
     TQWhatsThis::add( this, i18n("This picture of a monitor contains a preview of what the current settings will look like on your desktop.") );
 }
 
@@ -169,7 +191,7 @@ void BGMonitorLabel::updateMonitorGeometry()
 {
     double scaleX = double(width()) / double(sizeHint().width());
     double scaleY = double(height()) / double(sizeHint().height());
-    
+
     kdDebug() << k_funcinfo << " Setting geometry to " << TQRect( int(23*scaleX), int(14*scaleY), int(151*scaleX), int(115*scaleY) ) << endl;
     m_pBGMonitor->setGeometry( int(23*scaleX), int(14*scaleY), int(151*scaleX), int(115*scaleY) );
 }