Introducing the highlight window effect. When activated by the X atom

all windows are faded out except the one that is being highlighted.
It is nowhere near complete but committing it now so that the Plasma
developers can start playing around with it.

svn path=/trunk/KDE/kdebase/workspace/; revision=919159

effects/CMakeLists.txt

@@ -42,6 +42,7 @@ SET(kwin4_effect_builtins_sources
     fade.cpp
     fadedesktop.cpp
     fallapart.cpp
+    highlightwindow.cpp
     login.cpp
     logout.cpp
     magiclamp.cpp
@@ -67,6 +68,7 @@ install( FILES
     fade.desktop
     fadedesktop.desktop
     fallapart.desktop
+    highlightwindow.desktop
     login.desktop
     logout.desktop
     magiclamp.desktop

effects/highlightwindow.cpp

@@ -0,0 +1,99 @@
+/********************************************************************
+ KWin - the KDE window manager
+ This file is part of the KDE project.
+
+Copyright (C) 2009 Lucas Murray <lmurray@undefinedfire.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*********************************************************************/
+
+#include "highlightwindow.h"
+
+#include <kdebug.h>
+
+namespace KWin
+{
+
+KWIN_EFFECT( highlightwindow, HighlightWindowEffect )
+
+HighlightWindowEffect::HighlightWindowEffect()
+    : m_highlightedWindow( NULL )
+    , m_monitorWindow( NULL )
+    {
+    m_atom = XInternAtom( display(), "_KDE_WINDOW_HIGHLIGHT", False );
+    effects->registerPropertyType( m_atom, true );
+
+    // Announce support by creating a dummy version on the root window
+    unsigned char dummy = 0;
+    XChangeProperty( display(), rootWindow(), m_atom, m_atom, 8, PropModeReplace, &dummy, 1 );
+    }
+
+HighlightWindowEffect::~HighlightWindowEffect()
+    {
+    XDeleteProperty( display(), rootWindow(), m_atom );
+    effects->registerPropertyType( m_atom, false );
+    }
+
+void HighlightWindowEffect::prePaintWindow( EffectWindow* w, WindowPrePaintData& data, int time )
+    {
+    // If we are highlighting a window set the translucent flag to all others
+    if( m_highlightedWindow && m_highlightedWindow != w && m_monitorWindow != w && w->isNormalWindow() )
+        data.mask |= PAINT_WINDOW_TRANSLUCENT;
+    effects->prePaintWindow( w, data, time );
+    }
+
+void HighlightWindowEffect::paintWindow( EffectWindow* w, int mask, QRegion region, WindowPaintData& data )
+    {
+    if( m_highlightedWindow && m_highlightedWindow != w && m_monitorWindow != w && w->isNormalWindow() )
+        data.opacity *= 0.15; // TODO: Fade out
+    effects->paintWindow( w, mask, region, data );
+    }
+
+void HighlightWindowEffect::windowAdded( EffectWindow* w )
+    {
+    propertyNotify( w, m_atom ); // Check initial value
+    }
+
+void HighlightWindowEffect::windowDeleted( EffectWindow* w )
+    {
+    if( m_monitorWindow == w )
+        { // The monitoring window was destroyed
+        m_monitorWindow = NULL;
+        m_highlightedWindow = NULL;
+        }
+    }
+
+void HighlightWindowEffect::propertyNotify( EffectWindow* w, long a )
+    {
+    if( a != m_atom )
+        return; // Not our atom
+
+    QByteArray byteData = w->readProperty( m_atom, m_atom, 32 );
+    if( byteData.length() < 1 )
+        return; // Invalid length
+    long* data = reinterpret_cast<long*>( byteData.data() );
+
+    if( !data[0] )
+        { // Purposely clearing highlight
+        m_monitorWindow = NULL;
+        m_highlightedWindow = NULL;
+        return;
+        }
+    m_monitorWindow = w;
+    m_highlightedWindow = effects->findWindow( data[0] );
+    if( !m_highlightedWindow )
+        kDebug(1212) << "Invalid window targetted for highlight. Requested:" << data[0];
+    }
+
+} // namespace

effects/highlightwindow.desktop

@@ -0,0 +1,16 @@
+[Desktop Entry]
+Name=Highlight Window
+Icon=preferences-system-windows-effect-highlightwindow
+Comment=Highlight the appropriate window when hovering over taskbar entries
+
+Type=Service
+X-KDE-ServiceTypes=KWin/Effect
+X-KDE-PluginInfo-Author=Lucas Murray
+X-KDE-PluginInfo-Email=lmurray@undefinedfire.com
+X-KDE-PluginInfo-Name=kwin4_effect_highlightwindow
+X-KDE-PluginInfo-Version=0.1.0
+X-KDE-PluginInfo-Category=Appearance
+X-KDE-PluginInfo-Depends=
+X-KDE-PluginInfo-License=GPL
+X-KDE-PluginInfo-EnabledByDefault=true
+X-KDE-Library=kwin4_effect_builtins

effects/highlightwindow.h

@@ -0,0 +1,52 @@
+/********************************************************************
+ KWin - the KDE window manager
+ This file is part of the KDE project.
+
+Copyright (C) 2009 Lucas Murray <lmurray@undefinedfire.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*********************************************************************/
+
+#ifndef KWIN_HIGHLIGHTWINDOW_H
+#define KWIN_HIGHLIGHTWINDOW_H
+
+#include <kwineffects.h>
+
+namespace KWin
+{
+
+class HighlightWindowEffect
+    : public Effect
+    {
+    public:
+        HighlightWindowEffect();
+        virtual ~HighlightWindowEffect();
+
+        virtual void prePaintWindow( EffectWindow* w, WindowPrePaintData& data, int time );
+        virtual void paintWindow( EffectWindow* w, int mask, QRegion region, WindowPaintData& data );
+
+        virtual void windowAdded( EffectWindow* w );
+        virtual void windowDeleted( EffectWindow* w );
+
+        virtual void propertyNotify( EffectWindow* w, long atom );
+
+    private:
+        long m_atom;
+        EffectWindow* m_highlightedWindow;
+        EffectWindow* m_monitorWindow;
+    };
+
+} // namespace
+
+#endif