Use hiddenInternal() for a ShellClient which got unmapped

Summary:
So far when a ShellClient got unmapped ready_for_painting was set to
false. That is the ShellClient was treated in the same way as a not
yet shown window. It was completely excluded from painting, a close
animation impossible.

This change makes use of the functionality available in
Client::hiddenInternal(). The window is considered as hidden, thus
still excluded from e.g. getting input events, but could be rendered
any time as we still have a previous window pixmap (if referenced).
This allows to have it considered in the rendering pass, but effects
still cannot make use of it as that state is not yet exposed to the
effects.

Reviewers: #kwin, #plasma_on_wayland

Subscribers: plasma-devel, kwin

Tags: #plasma_on_wayland, #kwin

Differential Revision: https://phabricator.kde.org/D2083

abstract_client.h

@@ -294,6 +294,7 @@ public:
     virtual bool isCloseable() const = 0;
     // TODO: remove boolean trap
     virtual bool isShown(bool shaded_is_shown) const = 0;
+    virtual bool isHiddenInternal() const = 0;
     // TODO: remove boolean trap
     virtual void hideClient(bool hide) = 0;
     virtual bool isFullScreenable() const = 0;

autotests/integration/shell_client_test.cpp

@@ -98,6 +98,8 @@ void TestShellClient::testMapUnmapMap()
     auto client = clientAddedSpy.first().first().value<ShellClient*>();
     QVERIFY(client);
     QVERIFY(client->isShown(true));
+    QCOMPARE(client->isHiddenInternal(), false);
+    QCOMPARE(client->readyForPainting(), true);
     QCOMPARE(workspace()->activeClient(), client);
 
     // now unmap
@@ -108,6 +110,8 @@ void TestShellClient::testMapUnmapMap()
     surface->attachBuffer(Buffer::Ptr());
     surface->commit(Surface::CommitFlag::None);
     QVERIFY(hiddenSpy.wait());
+    QCOMPARE(client->readyForPainting(), true);
+    QCOMPARE(client->isHiddenInternal(), true);
     QVERIFY(windowClosedSpy.isEmpty());
     QVERIFY(!workspace()->activeClient());
 

client.h

@@ -167,7 +167,7 @@ public:
 
     /// Is not minimized and not hidden. I.e. normally visible on some virtual desktop.
     bool isShown(bool shaded_is_shown) const override;
-    bool isHiddenInternal() const; // For compositing
+    bool isHiddenInternal() const override; // For compositing
 
     ShadeMode shadeMode() const override; // Prefer isShade()
     void setShade(ShadeMode mode) override;

composite.cpp

@@ -749,9 +749,14 @@ bool Compositor::windowRepaintsPending() const
     if (!c->repaints().isEmpty())
         return true;
     if (auto w = waylandServer()) {
+        const bool locked = waylandServer()->isScreenLocked();
         const auto &clients = w->clients();
         for (auto c : clients) {
-            if (c->isShown(true) && !c->repaints().isEmpty()) {
+            if (locked && !c->isLockScreen() && !c->isInputMethod()) {
+                // ignore not visible windows while locked
+                continue;
+            }
+            if (c->readyForPainting() && !c->repaints().isEmpty()) {
                 return true;
             }
         }

input.cpp

@@ -1312,7 +1312,7 @@ Toplevel *InputRedirection::findToplevel(const QPoint &pos)
             continue;
         }
         if (AbstractClient *c = dynamic_cast<AbstractClient*>(t)) {
-            if (!c->isOnCurrentActivity() || !c->isOnCurrentDesktop() || c->isMinimized() || !c->isCurrentTab()) {
+            if (!c->isOnCurrentActivity() || !c->isOnCurrentDesktop() || c->isMinimized() || !c->isCurrentTab() || c->isHiddenInternal()) {
                 continue;
             }
         }

scene.cpp

@@ -800,10 +800,8 @@ void Scene::Window::resetPaintingEnabled()
             disable_painting |= PAINT_DISABLED_BY_MINIMIZE;
         if (c->tabGroup() && c != c->tabGroup()->current())
             disable_painting |= PAINT_DISABLED_BY_TAB_GROUP;
-        if (Client *cc = dynamic_cast<Client*>(c)) {
-            if (cc->isHiddenInternal()) {
-                disable_painting |= PAINT_DISABLED;
-            }
+        if (c->isHiddenInternal()) {
+            disable_painting |= PAINT_DISABLED;
         }
     }
 }

shell_client.cpp

@@ -339,7 +339,12 @@ void ShellClient::markAsMapped()
     }
 
     m_unmapped = false;
-    setReadyForPainting();
+    if (!ready_for_painting) {
+        setReadyForPainting();
+    } else {
+        addRepaintFull();
+        emit windowShown(this);
+    }
     if (shouldExposeToWindowManagement()) {
         setupWindowManagementInterface();
     }
@@ -868,7 +873,6 @@ void ShellClient::resizeWithChecks(int w, int h, ForceGeometry_t force)
 void ShellClient::unmap()
 {
     m_unmapped = true;
-    ready_for_painting = false;
     destroyWindowManagementInterface();
     if (Workspace::self()) {
         addWorkspaceRepaint(visibleRect());

shell_client.h

@@ -72,6 +72,9 @@ public:
     bool isMovableAcrossScreens() const override;
     bool isResizable() const override;
     bool isShown(bool shaded_is_shown) const override;
+    bool isHiddenInternal() const override {
+        return m_unmapped;
+    }
     void hideClient(bool hide) override;
     MaximizeMode maximizeMode() const override;
     QRect geometryRestore() const override {