Expose transientFor and only blur underneath when transientParent is dock

autotests/test_window_paint_data.cpp

@@ -46,6 +46,7 @@ public:
     void addLayerRepaint(const QRect &r) override;
     void addLayerRepaint(int x, int y, int w, int h) override;
     EffectWindow *findModal() override;
+    EffectWindow *transientFor() override;
     const EffectWindowGroup *group() const override;
     bool isPaintingEnabled() override;
     EffectWindowList mainWindows() const override;
@@ -340,6 +341,11 @@ EffectWindow *MockEffectWindow::findModal()
     return nullptr;
 }
 
+EffectWindow *MockEffectWindow::transientFor()
+{
+    return nullptr;
+}
+
 const EffectWindowGroup *MockEffectWindow::group() const
 {
     return nullptr;

effects.cpp

@@ -1984,6 +1984,21 @@ EffectWindow* EffectWindowImpl::findModal()
     return nullptr;
 }
 
+EffectWindow* EffectWindowImpl::transientFor()
+{
+    auto client = qobject_cast<AbstractClient *>(toplevel);
+    if (!client) {
+        return nullptr;
+    }
+
+    AbstractClient *transientFor = client->transientFor();
+    if (transientFor) {
+        return transientFor->effectWindow();
+    }
+
+    return nullptr;
+}
+
 QWindow *EffectWindowImpl::internalWindow() const
 {
     auto client = qobject_cast<InternalClient *>(toplevel);

effects.h

@@ -471,6 +471,7 @@ public:
     void deleteProperty(long atom) const override;
 
     EffectWindow* findModal() override;
+    EffectWindow* transientFor() override;
     EffectWindowList mainWindows() const override;
 
     WindowQuadList buildQuads(bool force = false) const override;

effects/blur/blur.cpp

@@ -604,9 +604,12 @@ void BlurEffect::drawWindow(EffectWindow *w, int mask, const QRegion &region, Wi
             shape = shape.translated(data.xTranslation(), data.yTranslation());
             shape = shape & region;
         }
+        
+        EffectWindow* modal = w->transientFor();
+        const bool transientForIsDock = (modal ? modal->isDock() : false);
 
         if (!shape.isEmpty()) {
-            doBlur(shape, screen, data.opacity(), data.screenProjectionMatrix(), w->isDock(), w->geometry());
+            doBlur(shape, screen, data.opacity(), data.screenProjectionMatrix(), w->isDock() || transientForIsDock, w->geometry());
         }
     }
 

libkwineffects/kwineffects.h

@@ -2373,6 +2373,7 @@ public:
 
     virtual bool isModal() const = 0;
     Q_SCRIPTABLE virtual KWin::EffectWindow* findModal() = 0;
+    Q_SCRIPTABLE virtual KWin::EffectWindow* transientFor() = 0;
     Q_SCRIPTABLE virtual QList<KWin::EffectWindow*> mainWindows() const = 0;
 
     /**