Move all dirty region scene repaint scheduling to Scene

The Compositor contains nothing that can potentially get dirty and need
repainting.

As is, the advantages of this move aren't really noticeable, but it
makes sense with multiple scenes.

Backend parts are far from ideal, they can be improved later on as we
progress with the scene redesign.

autotests/integration/buffer_size_change_test.cpp

@@ -56,7 +56,7 @@ void BufferSizeChangeTest::testShmBufferSizeChange()
     // add a first repaint
     QSignalSpy frameRenderedSpy(Compositor::self()->scene(), &Scene::frameRendered);
     QVERIFY(frameRenderedSpy.isValid());
-    Compositor::self()->addRepaintFull();
+    Compositor::self()->scene()->addRepaintFull();
     QVERIFY(frameRenderedSpy.wait());
 
     // now change buffer size
@@ -65,7 +65,7 @@ void BufferSizeChangeTest::testShmBufferSizeChange()
     QSignalSpy damagedSpy(client, &AbstractClient::damaged);
     QVERIFY(damagedSpy.isValid());
     QVERIFY(damagedSpy.wait());
-    KWin::Compositor::self()->addRepaintFull();
+    KWin::Compositor::self()->scene()->addRepaintFull();
     QVERIFY(frameRenderedSpy.wait());
 }
 
@@ -93,7 +93,7 @@ void BufferSizeChangeTest::testShmBufferSizeChangeOnSubSurface()
     // add a first repaint
     QSignalSpy frameRenderedSpy(Compositor::self()->scene(), &Scene::frameRendered);
     QVERIFY(frameRenderedSpy.isValid());
-    Compositor::self()->addRepaintFull();
+    Compositor::self()->scene()->addRepaintFull();
     QVERIFY(frameRenderedSpy.wait());
 
     // change buffer size of sub surface
@@ -105,7 +105,7 @@ void BufferSizeChangeTest::testShmBufferSizeChangeOnSubSurface()
     QVERIFY(damagedParentSpy.wait());
 
     // add a second repaint
-    KWin::Compositor::self()->addRepaintFull();
+    KWin::Compositor::self()->scene()->addRepaintFull();
     QVERIFY(frameRenderedSpy.wait());
 }
 

autotests/integration/generic_scene_opengl_test.cpp

@@ -13,6 +13,7 @@
 #include "cursor.h"
 #include "platform.h"
 #include "renderbackend.h"
+#include "scene.h"
 #include "wayland_server.h"
 
 #include <KConfigGroup>
@@ -80,7 +81,7 @@ void GenericSceneOpenGLTest::testRestart()
     QCOMPARE(kwinApp()->platform()->selectedCompositor(), KWin::OpenGLCompositing);
 
     // trigger a repaint
-    KWin::Compositor::self()->addRepaintFull();
+    KWin::Compositor::self()->scene()->addRepaintFull();
     // and wait 100 msec to ensure it's rendered
     // TODO: introduce frameRendered signal in SceneOpenGL
     QTest::qWait(100);

autotests/integration/scene_qpainter_test.cpp

@@ -87,7 +87,7 @@ void SceneQPainterTest::initTestCase()
 void SceneQPainterTest::testStartFrame()
 {
     // this test verifies that the initial rendering is correct
-    Compositor::self()->addRepaintFull();
+    Compositor::self()->scene()->addRepaintFull();
     auto scene = Compositor::self()->scene();
     QVERIFY(scene);
     QCOMPARE(kwinApp()->platform()->selectedCompositor(), QPainterCompositing);
@@ -261,7 +261,7 @@ void SceneQPainterTest::testCompositorRestart()
     QVERIFY(scene);
 
     // this should directly trigger a frame
-    KWin::Compositor::self()->addRepaintFull();
+    KWin::Compositor::self()->scene()->addRepaintFull();
     QSignalSpy frameRenderedSpy(scene, &Scene::frameRendered);
     QVERIFY(frameRenderedSpy.isValid());
     QVERIFY(frameRenderedSpy.wait());
@@ -360,7 +360,7 @@ void SceneQPainterTest::testX11Window()
     QVERIFY(scene);
 
     // this should directly trigger a frame
-    KWin::Compositor::self()->addRepaintFull();
+    KWin::Compositor::self()->scene()->addRepaintFull();
     QSignalSpy frameRenderedSpy(scene, &Scene::frameRendered);
     QVERIFY(frameRenderedSpy.isValid());
     QVERIFY(frameRenderedSpy.wait());

autotests/integration/xwaylandserver_crash_test.cpp

@@ -130,7 +130,7 @@ void XwaylandServerCrashTest::testCrash()
     QCOMPARE(kwinApp()->x11ScreenNumber(), -1);
 
     // Render a frame to ensure that the compositor doesn't crash.
-    Compositor::self()->addRepaintFull();
+    Compositor::self()->scene()->addRepaintFull();
     QSignalSpy frameRenderedSpy(Compositor::self()->scene(), &Scene::frameRendered);
     QVERIFY(frameRenderedSpy.wait());
 }

autotests/integration/xwaylandserver_restart_test.cpp

@@ -106,7 +106,7 @@ void XwaylandServerRestartTest::testRestart()
     QVERIFY(client->isDecorated());
 
     // Render a frame to ensure that the compositor doesn't crash.
-    Compositor::self()->addRepaintFull();
+    Compositor::self()->scene()->addRepaintFull();
     QSignalSpy frameRenderedSpy(Compositor::self()->scene(), &Scene::frameRendered);
     QVERIFY(frameRenderedSpy.wait());
 

src/backends/drm/drm_backend.cpp

@@ -18,6 +18,7 @@
 #include "logging.h"
 #include "main.h"
 #include "renderloop.h"
+#include "scene.h"
 #include "scene_qpainter_drm_backend.h"
 #include "session.h"
 #include "udev.h"
@@ -147,8 +148,8 @@ void DrmBackend::reactivate()
         output->renderLoop()->uninhibit();
     }
 
-    if (Compositor *compositor = Compositor::self()) {
-        compositor->addRepaintFull();
+    if (Compositor::compositing()) {
+        Compositor::self()->scene()->addRepaintFull();
     }
 
     // While the session had been inactive, an output could have been added or
@@ -712,8 +713,8 @@ bool DrmBackend::applyOutputChanges(const WaylandOutputConfig &config)
         }
     };
     updateCursor();
-    if (auto compositor = Compositor::self()) {
-        compositor->addRepaintFull();
+    if (Compositor::compositing()) {
+        Compositor::self()->scene()->addRepaintFull();
     }
     return true;
 }

src/backends/drm/drm_output.cpp

@@ -19,6 +19,7 @@
 #include "main.h"
 #include "renderloop.h"
 #include "renderloop_p.h"
+#include "scene.h"
 #include "screens.h"
 #include "session.h"
 #include "waylandoutputconfig.h"
@@ -267,8 +268,8 @@ bool DrmOutput::setDrmDpmsMode(DpmsMode mode)
         if (active) {
             m_renderLoop->uninhibit();
             m_gpu->platform()->checkOutputsAreOn();
-            if (Compositor *compositor = Compositor::self()) {
-                compositor->addRepaintFull();
+            if (Compositor::compositing()) {
+                Compositor::self()->scene()->addRepaintFull();
             }
         } else {
             m_renderLoop->inhibit();

src/backends/fbdev/scene_qpainter_fb_backend.cpp

@@ -13,6 +13,7 @@
 #include "main.h"
 #include "platform.h"
 #include "renderloop.h"
+#include "scene.h"
 #include "screens.h"
 #include "session.h"
 #include "vsyncmonitor.h"
@@ -50,7 +51,7 @@ void FramebufferQPainterBackend::reactivate()
     for (AbstractOutput *output : outputs) {
         output->renderLoop()->uninhibit();
     }
-    Compositor::self()->addRepaintFull();
+    Compositor::self()->scene()->addRepaintFull();
 }
 
 void FramebufferQPainterBackend::deactivate()

src/backends/wayland/wayland_backend.cpp

@@ -27,6 +27,7 @@
 #include "cursor.h"
 #include "input.h"
 #include "main.h"
+#include "scene.h"
 #include "screens.h"
 #include "pointer_input.h"
 #include "wayland_server.h"
@@ -200,7 +201,7 @@ void WaylandSubSurfaceCursor::move(const QPointF &globalPosition)
     // place the sub-surface relative to the output it is on and factor in the hotspot
     const auto relativePosition = globalPosition.toPoint() - Cursors::self()->currentCursor()->hotspot() - m_output->geometry().topLeft();
     m_subSurface->setPosition(relativePosition);
-    Compositor::self()->addRepaintFull();
+    Compositor::self()->scene()->addRepaintFull();
 }
 
 WaylandInputDevice::WaylandInputDevice(KWayland::Client::Keyboard *keyboard, WaylandSeat *seat)
@@ -859,7 +860,7 @@ WaylandOutput *WaylandBackend::createOutput(const QPoint &position, const QSize
     connect(waylandOutput, &WaylandOutput::sizeChanged, this, [this, waylandOutput](const QSize &size) {
         Q_UNUSED(size)
         updateScreenSize(waylandOutput);
-        Compositor::self()->addRepaintFull();
+        Compositor::self()->scene()->addRepaintFull();
     });
     connect(waylandOutput, &WaylandOutput::frameRendered, this, [waylandOutput]() {
         waylandOutput->resetRendered();

src/backends/x11/standalone/overlaywindow_x11.cpp

@@ -11,6 +11,7 @@
 
 #include "kwinglobals.h"
 #include "composite.h"
+#include "scene.h"
 #include "screens.h"
 #include "utils.h"
 #include "xcbutils.h"
@@ -167,7 +168,7 @@ bool OverlayWindowX11::event(xcb_generic_event_t *event)
         const auto *expose = reinterpret_cast<xcb_expose_event_t*>(event);
         if (expose->window == rootWindow()   // root window needs repainting
                 || (m_window != XCB_WINDOW_NONE && expose->window == m_window)) { // overlay needs repainting
-            Compositor::self()->addRepaint(expose->x, expose->y, expose->width, expose->height);
+            Compositor::self()->scene()->addRepaint(expose->x, expose->y, expose->width, expose->height);
         }
     } else if (eventType == XCB_VISIBILITY_NOTIFY) {
         const auto *visibility = reinterpret_cast<xcb_visibility_notify_event_t*>(event);
@@ -177,8 +178,12 @@ bool OverlayWindowX11::event(xcb_generic_event_t *event)
             auto compositor = Compositor::self();
             if (!was_visible && m_visible) {
                 // hack for #154825
-                compositor->addRepaintFull();
-                QTimer::singleShot(2000, compositor, &Compositor::addRepaintFull);
+                compositor->scene()->addRepaintFull();
+                QTimer::singleShot(2000, compositor, [compositor]() {
+                    if (compositor->compositing()) {
+                        compositor->scene()->addRepaintFull();
+                    }
+                });
             }
             compositor->scheduleRepaint();
         }

src/composite.cpp

@@ -353,6 +353,7 @@ void Compositor::startupWithWorkspace()
 
     Workspace::self()->markXStackingOrderAsDirty();
     Q_ASSERT(m_scene);
+    m_scene->initialize();
 
     const Platform *platform = kwinApp()->platform();
     if (platform->isPerScreenRenderingEnabled()) {
@@ -373,7 +374,6 @@ void Compositor::startupWithWorkspace()
     // Sets also the 'effects' pointer.
     kwinApp()->platform()->createEffectsHandler(this, m_scene);
     connect(Workspace::self(), &Workspace::deletedRemoved, m_scene, &Scene::removeToplevel);
-    connect(effects, &EffectsHandler::virtualScreenGeometryChanged, this, &Compositor::addRepaintFull);
 
     for (X11Client *c : Workspace::self()->clientList()) {
         c->setupCompositing();
@@ -399,7 +399,7 @@ void Compositor::startupWithWorkspace()
     }
 
     // Render at least once.
-    addRepaintFull();
+    m_scene->addRepaintFull();
 }
 
 void Compositor::registerRenderLoop(RenderLoop *renderLoop, AbstractOutput *output)
@@ -565,7 +565,6 @@ void Compositor::deleteUnusedSupportProperties()
 void Compositor::configChanged()
 {
     reinitialize();
-    addRepaintFull();
 }
 
 void Compositor::reinitialize()
@@ -582,28 +581,6 @@ void Compositor::reinitialize()
     }
 }
 
-void Compositor::addRepaint(int x, int y, int width, int height)
-{
-    addRepaint(QRegion(x, y, width, height));
-}
-
-void Compositor::addRepaint(const QRect &rect)
-{
-    addRepaint(QRegion(rect));
-}
-
-void Compositor::addRepaint(const QRegion &region)
-{
-    if (m_scene) {
-        m_scene->addRepaint(region);
-    }
-}
-
-void Compositor::addRepaintFull()
-{
-    addRepaint(screens()->geometry());
-}
-
 void Compositor::handleFrameRequested(RenderLoop *renderLoop)
 {
     composite(renderLoop);

src/composite.h

@@ -41,13 +41,6 @@ public:
     ~Compositor() override;
     static Compositor *self();
 
-    // when adding repaints caused by a window, you probably want to use
-    // either Toplevel::addRepaint() or Toplevel::addWorkspaceRepaint()
-    void addRepaint(const QRect& r);
-    void addRepaint(const QRegion& r);
-    void addRepaint(int x, int y, int w, int h);
-    void addRepaintFull();
-
     /**
      * Schedules a new repaint if no repaint is currently scheduled.
      */

src/effects.cpp

@@ -1172,22 +1172,22 @@ EffectWindow* EffectsHandlerImpl::currentTabBoxWindow() const
 
 void EffectsHandlerImpl::addRepaintFull()
 {
-    m_compositor->addRepaintFull();
+    m_compositor->scene()->addRepaintFull();
 }
 
 void EffectsHandlerImpl::addRepaint(const QRect& r)
 {
-    m_compositor->addRepaint(r);
+    m_compositor->scene()->addRepaint(r);
 }
 
 void EffectsHandlerImpl::addRepaint(const QRegion& r)
 {
-    m_compositor->addRepaint(r);
+    m_compositor->scene()->addRepaint(r);
 }
 
 void EffectsHandlerImpl::addRepaint(int x, int y, int w, int h)
 {
-    m_compositor->addRepaint(x, y, w, h);
+    m_compositor->scene()->addRepaint(x, y, w, h);
 }
 
 EffectScreen *EffectsHandlerImpl::activeScreen() const
@@ -1349,7 +1349,7 @@ QStringList EffectsHandlerImpl::listOfEffects() const
 bool EffectsHandlerImpl::loadEffect(const QString& name)
 {
     makeOpenGLContextCurrent();
-    m_compositor->addRepaintFull();
+    m_compositor->scene()->addRepaintFull();
 
     return m_effectLoader->loadEffect(name);
 }
@@ -1371,7 +1371,7 @@ void EffectsHandlerImpl::unloadEffect(const QString& name)
     effect_order.erase(it);
     effectsChanged();
 
-    m_compositor->addRepaintFull();
+    m_compositor->scene()->addRepaintFull();
 }
 
 void EffectsHandlerImpl::destroyEffect(Effect *effect)

src/item.cpp

@@ -10,6 +10,7 @@
 #include "main.h"
 #include "platform.h"
 #include "renderloop.h"
+#include "scene.h"
 #include "screens.h"
 #include "utils.h"
 
@@ -27,7 +28,7 @@ Item::~Item()
     setParentItem(nullptr);
     for (const auto &dirty : qAsConst(m_repaints)) {
         if (!dirty.isEmpty()) {
-            Compositor::self()->addRepaint(dirty);
+            Compositor::self()->scene()->addRepaint(dirty);
         }
     }
 }

src/layers.cpp

@@ -114,9 +114,6 @@ void Workspace::updateStackingOrder(bool propagate_new_clients)
         }
 
         Q_EMIT stackingOrderChanged();
-        if (m_compositor) {
-            m_compositor->addRepaintFull();
-        }
 
         if (active_client)
             active_client->updateMouseGrab();

src/platform.cpp

@@ -269,11 +269,10 @@ void Platform::setSoftwareCursorForced(bool forced)
 
 void Platform::triggerCursorRepaint()
 {
-    if (!Compositor::self()) {
-        return;
+    if (Compositor::compositing()) {
+        Compositor::self()->scene()->addRepaint(m_cursor.lastRenderedGeometry);
+        Compositor::self()->scene()->addRepaint(Cursors::self()->currentCursor()->geometry());
     }
-    Compositor::self()->addRepaint(m_cursor.lastRenderedGeometry);
-    Compositor::self()->addRepaint(Cursors::self()->currentCursor()->geometry());
 }
 
 void Platform::cursorRendered(const QRect &geometry)
@@ -469,10 +468,9 @@ void Platform::processPinchGestureCancelled(quint32 time)
 
 void Platform::repaint(const QRect &rect)
 {
-    if (!Compositor::self()) {
-        return;
+    if (Compositor::compositing()) {
+        Compositor::self()->scene()->addRepaint(rect);
     }
-    Compositor::self()->addRepaint(rect);
 }
 
 void Platform::setReady(bool ready)

src/plugins/screencast/screencastmanager.cpp

@@ -151,7 +151,7 @@ void ScreencastManager::streamOutput(KWaylandServer::ScreencastStreamV1Interface
         stream->recordFrame(texture.data(), region);
     };
     connect(stream, &PipeWireStream::startStreaming, waylandStream, [streamOutput, stream, bufferToStream] {
-        Compositor::self()->addRepaint(streamOutput->geometry());
+        Compositor::self()->scene()->addRepaint(streamOutput->geometry());
         streamOutput->recordingStarted();
         connect(streamOutput, &AbstractWaylandOutput::outputChange, stream, bufferToStream);
     });

src/scene.cpp

@@ -61,6 +61,7 @@
 #include "unmanaged.h"
 #include "waylandclient.h"
 #include "windowitem.h"
+#include "workspace.h"
 #include "x11client.h"
 
 #include <QQuickWindow>
@@ -86,7 +87,6 @@ namespace KWin
 Scene::Scene(QObject *parent)
     : QObject(parent)
 {
-    connect(kwinApp()->platform(), &Platform::outputDisabled, this, &Scene::removeRepaints);
 }
 
 Scene::~Scene()
@@ -94,6 +94,30 @@ Scene::~Scene()
     Q_ASSERT(m_windows.isEmpty());
 }
 
+void Scene::initialize()
+{
+    connect(kwinApp()->platform(), &Platform::outputDisabled, this, &Scene::removeRepaints);
+
+    connect(workspace(), &Workspace::geometryChanged, this, &Scene::addRepaintFull);
+    connect(workspace(), &Workspace::currentDesktopChanged, this, &Scene::addRepaintFull);
+    connect(workspace(), &Workspace::stackingOrderChanged, this, &Scene::addRepaintFull);
+}
+
+void Scene::addRepaintFull()
+{
+    addRepaint(workspace()->geometry());
+}
+
+void Scene::addRepaint(int x, int y, int width, int height)
+{
+    addRepaint(QRegion(x, y, width, height));
+}
+
+void Scene::addRepaint(const QRect &rect)
+{
+    addRepaint(QRegion(rect));
+}
+
 void Scene::addRepaint(const QRegion &region)
 {
     if (kwinApp()->platform()->isPerScreenRenderingEnabled()) {

src/scene.h

@@ -53,10 +53,15 @@ public:
     class EffectFrame;
     class Window;
 
+    void initialize();
+
     /**
      * Schedules a repaint for the specified @a region.
      */
     void addRepaint(const QRegion &region);
+    void addRepaint(const QRect &rect);
+    void addRepaint(int x, int y, int width, int height);
+    void addRepaintFull();
 
     /**
      * Returns the repaints region for output with the specified @a output.

src/toplevel.cpp

@@ -344,15 +344,15 @@ void Toplevel::addWorkspaceRepaint(int x, int y, int w, int h)
 
 void Toplevel::addWorkspaceRepaint(const QRect& r2)
 {
-    if (!Compositor::compositing())
-        return;
-    Compositor::self()->addRepaint(r2);
+    if (Compositor::compositing()) {
+        Compositor::self()->scene()->addRepaint(r2);
+    }
 }
 
 void Toplevel::addWorkspaceRepaint(const QRegion &region)
 {
     if (Compositor::compositing()) {
-        Compositor::self()->addRepaint(region);
+        Compositor::self()->scene()->addRepaint(region);
     }
 }
 

src/workspace.cpp

@@ -180,7 +180,6 @@ Workspace::Workspace()
         Q_ASSERT(kwinApp()->operationMode() == Application::OperationMode::OperationModeX11);
         m_compositor = X11Compositor::create(this);
     }
-    connect(this, &Workspace::currentDesktopChanged, m_compositor, &Compositor::addRepaintFull);
     connect(m_compositor, &QObject::destroyed, this, [this] { m_compositor = nullptr; });
 
     auto decorationBridge = Decoration::DecorationBridge::create(this);
@@ -1192,7 +1191,7 @@ void Workspace::updateCurrentActivity(const QString &new_activity)
     //if ( effects != NULL && old_desktop != 0 && old_desktop != new_desktop )
     //    static_cast<EffectsHandlerImpl*>( effects )->desktopChanged( old_desktop );
     if (Compositor::compositing() && m_compositor)
-        m_compositor->addRepaintFull();
+        m_compositor->scene()->addRepaintFull();
 #else
     Q_UNUSED(new_activity)
 #endif