add screen inversion through XF86VidModeSetGammaRamp or XRRSetCrtcGamma

use opengl invert effect as fallback

REVIEW: 104371

effects.cpp

@@ -270,12 +270,12 @@ void EffectsHandlerImpl::postPaintWindow(EffectWindow* w)
     // no special final code
 }
 
-bool EffectsHandlerImpl::provides(Effect::Feature ef)
+Effect *EffectsHandlerImpl::provides(Effect::Feature ef)
 {
     for (int i = 0; i < loaded_effects.size(); ++i)
         if (loaded_effects.at(i).second->provides(ef))
-            return true;
-    return false;
+            return loaded_effects.at(i).second;
+    return NULL;
 }
 
 void EffectsHandlerImpl::drawWindow(EffectWindow* w, int mask, QRegion region, WindowPaintData& data)

effects.h

@@ -57,7 +57,7 @@ public:
     virtual void postPaintWindow(EffectWindow* w);
     virtual void paintEffectFrame(EffectFrame* frame, QRegion region, double opacity, double frameOpacity);
 
-    bool provides(Effect::Feature ef);
+    Effect *provides(Effect::Feature ef);
 
     virtual void drawWindow(EffectWindow* w, int mask, QRegion region, WindowPaintData& data);
 

effects/invert/invert.cpp

@@ -48,7 +48,7 @@ InvertEffect::InvertEffect()
     KAction* a = (KAction*)actionCollection->addAction("Invert");
     a->setText(i18n("Toggle Invert Effect"));
     a->setGlobalShortcut(KShortcut(Qt::CTRL + Qt::META + Qt::Key_I));
-    connect(a, SIGNAL(triggered(bool)), this, SLOT(toggle()));
+    connect(a, SIGNAL(triggered(bool)), this, SLOT(toggleScreenInversion()));
 
     KAction* b = (KAction*)actionCollection->addAction("InvertWindow");
     b->setText(i18n("Toggle Invert Effect on Window"));
@@ -143,7 +143,7 @@ void InvertEffect::slotWindowClosed(EffectWindow* w)
     m_windows.removeOne(w);
 }
 
-void InvertEffect::toggle()
+void InvertEffect::toggleScreenInversion()
 {
     m_allWindows = !m_allWindows;
     effects->addRepaintFull();
@@ -163,6 +163,11 @@ bool InvertEffect::isActive() const
     return m_valid && (m_allWindows || !m_windows.isEmpty());
 }
 
+bool InvertEffect::provides(Feature f)
+{
+    return f == ScreenInversion;
+}
+
 } // namespace
 
 #include "invert.moc"

effects/invert/invert.h

@@ -45,11 +45,12 @@ public:
     virtual void prePaintWindow(EffectWindow *w, WindowPrePaintData &data, int time);
     virtual void paintEffectFrame(KWin::EffectFrame* frame, QRegion region, double opacity, double frameOpacity);
     virtual bool isActive() const;
+    virtual bool provides(Feature);
 
     static bool supported();
 
 public slots:
-    void toggle();
+    void toggleScreenInversion();
     void toggleWindow();
     void slotWindowClosed(KWin::EffectWindow *w);
 

kwinbindings.cpp

@@ -191,6 +191,7 @@ a->setText(i18n("Miscellaneous"));
 DEF(I18N_NOOP("Kill Window"),                      Qt::CTRL + Qt::ALT + Qt::Key_Escape, slotKillWindow());
 DEF(I18N_NOOP("Block Global Shortcuts"),           0, slotDisableGlobalShortcuts());
 DEF(I18N_NOOP("Suspend Compositing"),              Qt::SHIFT + Qt::ALT + Qt::Key_F12, slotToggleCompositing());
+DEF(I18N_NOOP("Invert Screen Colors"),              0, slotInvertScreen());
 
 #undef DEF
 #undef DEF2

libkwineffects/kwineffects.h

@@ -320,8 +320,7 @@ public:
     };
 
     enum Feature {
-        Nothing = 0, Resize, GeometryTip,
-        Outline
+        Nothing = 0, Resize, GeometryTip, Outline, ScreenInversion
     };
 
     /**
@@ -415,7 +414,7 @@ public:
 
     /**
      * Called on Transparent resizes.
-     * return true if your effect substitutes the XOR rubberband
+     * return true if your effect substitutes questioned feature
     */
     virtual bool provides(Feature);
 

useractions.cpp

@@ -44,6 +44,10 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <KActivities/Info>
 #endif
 
+#include <X11/extensions/Xrandr.h>
+#ifndef KWIN_NO_XF86VM
+#include <X11/extensions/xf86vmode.h>
+#endif
 #include <fixx11h.h>
 #include <QPushButton>
 #include <QSlider>
@@ -1615,6 +1619,80 @@ void Workspace::slotWindowResize()
         performWindowOperation(active_client, Options::UnrestrictedResizeOp);
 }
 
+void Workspace::slotInvertScreen()
+{
+    bool succeeded = false;
+
+    //BEGIN Xrandr inversion - does atm NOT work with the nvidia blob
+    XRRScreenResources *res = XRRGetScreenResources(display(), active_client ? active_client->window() : rootWindow());
+    if (res) {
+        for (int j = 0; j < res->ncrtc; ++j) {
+            XRRCrtcGamma *gamma = XRRGetCrtcGamma(display(), res->crtcs[j]);
+            if (gamma && gamma->size) {
+                kDebug(1212) << "inverting screen using XRRSetCrtcGamma";
+                const int half = gamma->size / 2 + 1;
+                unsigned short swap;
+                for (int i = 0; i < half; ++i) {
+#define INVERT(_C_) swap = gamma->_C_[i]; gamma->_C_[i] = gamma->_C_[gamma->size - 1 - i]; gamma->_C_[gamma->size - 1 - i] = swap
+                    INVERT(red);
+                    INVERT(green);
+                    INVERT(blue);
+#undef INVERT
+                }
+                XRRSetCrtcGamma(display(), res->crtcs[j], gamma);
+                XRRFreeGamma(gamma);
+                succeeded = true;
+            }
+        }
+        XRRFreeScreenResources(res);
+    }
+    if (succeeded)
+        return;
+
+    //BEGIN XF86VidMode inversion - only works if optionally libXxf86vm is linked
+#ifndef KWIN_NO_XF86VM
+    int size = 0;
+    // TODO: this doesn't work with screen numbers in twinview - probably relevant only for multihead?
+    const int scrn = 0; // active_screen
+    if (XF86VidModeGetGammaRampSize(display(), scrn, &size)) {
+        unsigned short *red, *green, *blue;
+        red = new unsigned short[size];
+        green = new unsigned short[size];
+        blue = new unsigned short[size];
+        if (XF86VidModeGetGammaRamp(display(), scrn, size, red, green, blue)) {
+            kDebug(1212) << "inverting screen using XF86VidModeSetGammaRamp";
+            const int half = size / 2 + 1;
+            unsigned short swap;
+            for (int i = 0; i < half; ++i) {
+                swap = red[i]; red[i] = red[size - 1 - i]; red[size - 1 - i] = swap;
+                swap = green[i]; green[i] = green[size - 1 - i]; green[size - 1 - i] = swap;
+                swap = blue[i]; blue[i] = blue[size - 1 - i]; blue[size - 1 - i] = swap;
+            }
+            XF86VidModeSetGammaRamp(display(), scrn, size, red, green, blue);
+            succeeded = true;
+        }
+        delete [] red;
+        delete [] green;
+        delete [] blue;
+    }
+
+    if (succeeded)
+        return;
+#endif
+
+    //BEGIN effect plugin inversion - atm only works with OpenGL and has an overhead to it
+    if (effects) {
+        if (Effect *inverter = static_cast<EffectsHandlerImpl*>(effects)->provides(Effect::ScreenInversion)) {
+            kDebug(1212) << "inverting screen using Effect plugin";
+            QMetaObject::invokeMethod(inverter, "toggleScreenInversion", Qt::DirectConnection);
+        }
+    }
+
+    if (!succeeded)
+        kDebug(1212) << "sorry - neither Xrandr, nor XF86VidModeSetGammaRamp worked and there's no inversion supplying effect plugin either";
+
+}
+
 #undef USABLE_ACTIVE_CLIENT
 
 void Client::setShortcut(const QString& _cut)

workspace.h

@@ -622,6 +622,7 @@ public slots:
     void slotSetupWindowShortcut();
     void setupWindowShortcutDone(bool);
     void slotToggleCompositing();
+    void slotInvertScreen();
 
     void updateClientArea();
     void suspendCompositing();