Translucency Effect supports isActive hook

The effect gets a set of boolean values to check whether it is active for
one of the categories (e.g. move resize, decorations).

This allows to easily check whether the effect is active at all, that is
if all values are at 1.0 the effect will never affect a window.

In all other cases it can be combined with looking at the available
windows to e.g. enable the effect for move resize only when there is a
window which is either moved or resized. This check is performed whenever
an action happens which could cause a window to become inactive.

BUG: 306262
FIXED-IN: 4.9.2

effects/translucency/translucency.cpp

@@ -31,10 +31,19 @@ TranslucencyEffect::TranslucencyEffect()
     : fadeout(NULL)
     , current(NULL)
     , previous(NULL)
+    , m_activeDecorations(false)
+    , m_activeMoveResize(false)
+    , m_activeDialogs(false)
+    , m_activeInactive(false)
+    , m_activeCombobox(false)
+    , m_activeMenus(false)
+    , m_active(false)
 {
     reconfigure(ReconfigureAll);
     active = effects->activeWindow();
     connect(effects, SIGNAL(windowActivated(KWin::EffectWindow*)), this, SLOT(slotWindowActivated(KWin::EffectWindow*)));
+    connect(effects, SIGNAL(windowAdded(KWin::EffectWindow*)), this, SLOT(checkIsActive()));
+    connect(effects, SIGNAL(windowDeleted(KWin::EffectWindow*)), this, SLOT(checkIsActive()));
     connect(effects, SIGNAL(windowStartUserMovedResized(KWin::EffectWindow*)), this, SLOT(slotWindowStartStopUserMovedResized(KWin::EffectWindow*)));
     connect(effects, SIGNAL(windowFinishUserMovedResized(KWin::EffectWindow*)), this, SLOT(slotWindowStartStopUserMovedResized(KWin::EffectWindow*)));
 }
@@ -63,10 +72,88 @@ void TranslucencyEffect::reconfigure(ReconfigureFlags)
     activeinactive_timeline.setCurveShape(QTimeLine::EaseInOutCurve);
     activeinactive_timeline.setDuration(animationTime(conf, "Duration", 800));
 
+    m_activeDecorations = !qFuzzyCompare(decoration, 1.0);
+    m_activeMoveResize = !qFuzzyCompare(moveresize, 1.0);
+    m_activeDialogs = !qFuzzyCompare(dialogs, 1.0);
+    m_activeInactive = !qFuzzyCompare(inactive, 1.0);
+    m_activeCombobox = !qFuzzyCompare(comboboxpopups, 1.0);
+    m_activeMenus = !qFuzzyCompare(menus, 1.0);
+    if (!m_activeMenus && individualmenuconfig) {
+        m_activeMenus = !qFuzzyCompare(dropdownmenus, 1.0) ||
+                        !qFuzzyCompare(popupmenus, 1.0) ||
+                        !qFuzzyCompare(tornoffmenus, 1.0);
+    }
+    checkIsActive();
+
     // Repaint the screen just in case the user changed the inactive opacity
     effects->addRepaintFull();
 }
 
+void TranslucencyEffect::checkIsActive()
+{
+    m_active = m_activeDecorations ||
+               m_activeMoveResize ||
+               m_activeDialogs ||
+               m_activeInactive ||
+               m_activeCombobox ||
+               m_activeMenus;
+    if (!m_active) {
+        // all individual options are disabled, no window state can activate it
+        return;
+    }
+    if (m_activeDecorations) {
+        // we can assume that there is at least one decorated window, so the effect is active
+        return;
+    }
+    if (m_activeInactive) {
+        // we can assume that there is at least one inactive window, so the effect is active
+        // TODO: maybe only if inactive window is not obscured?
+        return;
+    }
+    // for all other options we go through the list of window and search for a Window being affected
+    bool activeDropdown, activePopup, activeTornoff;
+    activeDropdown = activePopup = activeTornoff = false;
+    if (individualmenuconfig) {
+        activeDropdown = !qFuzzyCompare(dropdownmenus, 1.0);
+        activePopup = !qFuzzyCompare(popupmenus, 1.0);
+        activeTornoff = !qFuzzyCompare(activeTornoff, 1.0);
+    }
+    foreach (EffectWindow *w, effects->stackingOrder()) {
+        if (w->isDeleted()) {
+            // ignore deleted windows
+            continue;
+        }
+        if (m_activeMoveResize && (w->isUserMove() || w->isUserResize())) {
+            return;
+        }
+        if (m_activeDialogs && w->isDialog()) {
+            return;
+        }
+        if (m_activeCombobox && w->isComboBox()) {
+            return;
+        }
+        if (m_activeMenus) {
+            if (individualmenuconfig) {
+                if (activeDropdown && w->isDropdownMenu()) {
+                    return;
+                }
+                if (activePopup && w->isPopupMenu()) {
+                    return;
+                }
+                if (activeTornoff && w->isMenu()) {
+                    return;
+                }
+            } else {
+                if (w->isMenu() || w->isDropdownMenu() || w->isPopupMenu()) {
+                    return;
+                }
+            }
+        }
+    }
+    // no matching window, disable effect
+    m_active = false;
+}
+
 void TranslucencyEffect::prePaintWindow(EffectWindow* w, WindowPrePaintData& data, int time)
 {
     // We keep track of the windows that was last active so we know
@@ -183,7 +270,8 @@ bool TranslucencyEffect::isInactive(const EffectWindow* w) const
 
 void TranslucencyEffect::slotWindowStartStopUserMovedResized(EffectWindow* w)
 {
-    if (moveresize != 1.0) {
+    if (m_activeMoveResize) {
+        checkIsActive();
         moveresize_timeline.setCurrentTime(0);
         w->addRepaintFull();
     }
@@ -213,6 +301,12 @@ void TranslucencyEffect::slotWindowActivated(EffectWindow* w)
         }
     }
     active = w;
+    checkIsActive();
+}
+
+bool TranslucencyEffect::isActive() const
+{
+    return m_active;
 }
 
 } // namespace

effects/translucency/translucency.h

@@ -48,6 +48,7 @@ public:
     virtual void reconfigure(ReconfigureFlags);
     virtual void prePaintWindow(EffectWindow* w, WindowPrePaintData& data, int time);
     virtual void paintWindow(EffectWindow* w, int mask, QRegion region, WindowPaintData& data);
+    virtual bool isActive() const;
 
     // for properties
     qreal configuredDecoration() const {
@@ -90,6 +91,9 @@ public Q_SLOTS:
     void slotWindowActivated(KWin::EffectWindow* w);
     void slotWindowStartStopUserMovedResized(KWin::EffectWindow *w);
 
+private Q_SLOTS:
+    void checkIsActive();
+
 private:
     bool isInactive(const EffectWindow *w) const;
     bool individualmenuconfig;
@@ -111,6 +115,14 @@ private:
 
     QTimeLine moveresize_timeline;
     QTimeLine activeinactive_timeline;
+
+    bool m_activeDecorations;
+    bool m_activeMoveResize;
+    bool m_activeDialogs;
+    bool m_activeInactive;
+    bool m_activeCombobox;
+    bool m_activeMenus;
+    bool m_active;
 };
 
 } // namespace