File indexing completed on 2024-04-28 05:30:13

 /*
     KWin - the KDE window manager
     This file is part of the KDE project.
 
     SPDX-FileCopyrightText: 2006 Lubos Lunak <l.lunak@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #include "compositor_wayland.h"
 #include "core/output.h"
 #include "core/outputbackend.h"
 #include "core/renderbackend.h"
 #include "core/renderlayer.h"
 #include "effect/effecthandler.h"
 #include "main.h"
 #include "opengl/glplatform.h"
 #include "platformsupport/scenes/opengl/openglbackend.h"
 #include "platformsupport/scenes/qpainter/qpainterbackend.h"
 #include "scene/cursordelegate_opengl.h"
 #include "scene/cursordelegate_qpainter.h"
 #include "scene/cursorscene.h"
 #include "scene/itemrenderer_opengl.h"
 #include "scene/itemrenderer_qpainter.h"
 #include "scene/workspacescene_opengl.h"
 #include "scene/workspacescene_qpainter.h"
 #include "window.h"
 #include "workspace.h"
 
 #include <QQuickWindow>
 
 namespace KWin
 {
 
 WaylandCompositor *WaylandCompositor::create(QObject *parent)
 {
     Q_ASSERT(!s_compositor);
     auto *compositor = new WaylandCompositor(parent);
     s_compositor = compositor;
     return compositor;
 }
 
 WaylandCompositor::WaylandCompositor(QObject *parent)
     : Compositor(parent)
 {
 }
 
 WaylandCompositor::~WaylandCompositor()
 {
     Q_EMIT aboutToDestroy();
     stop(); // this can't be called in the destructor of Compositor
 }
 
 bool WaylandCompositor::attemptOpenGLCompositing()
 {
     std::unique_ptr<OpenGLBackend> backend = kwinApp()->outputBackend()->createOpenGLBackend();
     if (!backend) {
         return false;
     }
     if (!backend->isFailed()) {
         backend->init();
     }
     if (backend->isFailed()) {
         return false;
     }
 
     const QByteArray forceEnv = qgetenv("KWIN_COMPOSE");
     if (!forceEnv.isEmpty()) {
         if (qstrcmp(forceEnv, "O2") == 0 || qstrcmp(forceEnv, "O2ES") == 0) {
             qCDebug(KWIN_CORE) << "OpenGL 2 compositing enforced by environment variable";
         } else {
             // OpenGL 2 disabled by environment variable
             return false;
         }
     } else {
         if (GLPlatform::instance()->recommendedCompositor() < OpenGLCompositing) {
             qCDebug(KWIN_CORE) << "Driver does not recommend OpenGL compositing";
             return false;
         }
     }
 
     // We only support the OpenGL 2+ shader API, not GL_ARB_shader_objects
     if (!hasGLVersion(2, 0)) {
         qCDebug(KWIN_CORE) << "OpenGL 2.0 is not supported";
         return false;
     }
 
     m_scene = std::make_unique<WorkspaceSceneOpenGL>(backend.get());
     m_cursorScene = std::make_unique<CursorScene>(std::make_unique<ItemRendererOpenGL>());
     m_backend = std::move(backend);
 
     qCDebug(KWIN_CORE) << "OpenGL compositing has been successfully initialized";
     return true;
 }
 
 bool WaylandCompositor::attemptQPainterCompositing()
 {
     std::unique_ptr<QPainterBackend> backend(kwinApp()->outputBackend()->createQPainterBackend());
     if (!backend || backend->isFailed()) {
         return false;
     }
 
     m_scene = std::make_unique<WorkspaceSceneQPainter>(backend.get());
     m_cursorScene = std::make_unique<CursorScene>(std::make_unique<ItemRendererQPainter>());
     m_backend = std::move(backend);
 
     qCDebug(KWIN_CORE) << "QPainter compositing has been successfully initialized";
     return true;
 }
 
 void WaylandCompositor::start()
 {
     if (kwinApp()->isTerminating()) {
         return;
     }
     if (m_state != State::Off) {
         return;
     }
 
     Q_EMIT aboutToToggleCompositing();
     m_state = State::Starting;
 
     // If compositing has been restarted, try to use the last used compositing type.
     const QList<CompositingType> availableCompositors = kwinApp()->outputBackend()->supportedCompositors();
     QList<CompositingType> candidateCompositors;
 
     if (m_selectedCompositor != NoCompositing) {
         candidateCompositors.append(m_selectedCompositor);
     } else {
         candidateCompositors = availableCompositors;
 
         const auto userConfigIt = std::find(candidateCompositors.begin(), candidateCompositors.end(), options->compositingMode());
         if (userConfigIt != candidateCompositors.end()) {
             candidateCompositors.erase(userConfigIt);
             candidateCompositors.prepend(options->compositingMode());
         } else {
             qCWarning(KWIN_CORE) << "Configured compositor not supported by Platform. Falling back to defaults";
         }
     }
 
     for (auto type : std::as_const(candidateCompositors)) {
         bool stop = false;
         switch (type) {
         case OpenGLCompositing:
             qCDebug(KWIN_CORE) << "Attempting to load the OpenGL scene";
             stop = attemptOpenGLCompositing();
             break;
         case QPainterCompositing:
             qCDebug(KWIN_CORE) << "Attempting to load the QPainter scene";
             stop = attemptQPainterCompositing();
             break;
         case NoCompositing:
             qCDebug(KWIN_CORE) << "Starting without compositing...";
             stop = true;
             break;
         }
 
         if (stop) {
             break;
         } else if (qEnvironmentVariableIsSet("KWIN_COMPOSE")) {
             qCCritical(KWIN_CORE) << "Could not fulfill the requested compositing mode in KWIN_COMPOSE:" << type << ". Exiting.";
             qApp->quit();
         }
     }
 
     if (!m_backend) {
         m_state = State::Off;
 
         qCCritical(KWIN_CORE) << "The used windowing system requires compositing";
         qCCritical(KWIN_CORE) << "We are going to quit KWin now as it is broken";
         qApp->quit();
         return;
     }
 
     if (m_selectedCompositor == NoCompositing) {
         m_selectedCompositor = m_backend->compositingType();
 
         switch (m_selectedCompositor) {
         case NoCompositing:
             break;
         case OpenGLCompositing:
             QQuickWindow::setGraphicsApi(QSGRendererInterface::OpenGL);
             break;
         case QPainterCompositing:
             QQuickWindow::setGraphicsApi(QSGRendererInterface::Software);
             break;
         }
     }
 
     Q_EMIT sceneCreated();
 
     const QList<Output *> outputs = workspace()->outputs();
     for (Output *output : outputs) {
         addOutput(output);
     }
     connect(workspace(), &Workspace::outputAdded, this, &WaylandCompositor::addOutput);
     connect(workspace(), &Workspace::outputRemoved, this, &WaylandCompositor::removeOutput);
 
     m_state = State::On;
 
     const auto windows = workspace()->windows();
     for (Window *window : windows) {
         window->setupCompositing();
     }
 
     // Sets also the 'effects' pointer.
     kwinApp()->createEffectsHandler(this, m_scene.get());
 
     Q_EMIT compositingToggled(true);
 }
 
 void WaylandCompositor::stop()
 {
     if (m_state == State::Off || m_state == State::Stopping) {
         return;
     }
     m_state = State::Stopping;
     Q_EMIT aboutToToggleCompositing();
 
     // Some effects might need access to effect windows when they are about to
     // be destroyed, for example to unreference deleted windows, so we have to
     // make sure that effect windows outlive effects.
     delete effects;
     effects = nullptr;
 
     if (Workspace::self()) {
         const auto windows = workspace()->windows();
         for (Window *window : windows) {
             window->finishCompositing();
         }
         disconnect(workspace(), &Workspace::outputAdded, this, &WaylandCompositor::addOutput);
         disconnect(workspace(), &Workspace::outputRemoved, this, &WaylandCompositor::removeOutput);
     }
 
     if (m_backend->compositingType() == OpenGLCompositing) {
         // some layers need a context current for destruction
         static_cast<OpenGLBackend *>(m_backend.get())->makeCurrent();
     }
 
     const auto superlayers = m_superlayers;
     for (auto it = superlayers.begin(); it != superlayers.end(); ++it) {
         removeSuperLayer(*it);
     }
 
     m_scene.reset();
     m_cursorScene.reset();
     m_backend.reset();
 
     m_state = State::Off;
     Q_EMIT compositingToggled(false);
 }
 
 void WaylandCompositor::addOutput(Output *output)
 {
     if (output->isPlaceholder()) {
         return;
     }
     auto workspaceLayer = new RenderLayer(output->renderLoop());
     workspaceLayer->setDelegate(std::make_unique<SceneDelegate>(m_scene.get(), output));
     workspaceLayer->setGeometry(output->rectF());
     connect(output, &Output::geometryChanged, workspaceLayer, [output, workspaceLayer]() {
         workspaceLayer->setGeometry(output->rectF());
     });
 
     auto cursorLayer = new RenderLayer(output->renderLoop());
     cursorLayer->setVisible(false);
     if (m_backend->compositingType() == OpenGLCompositing) {
         cursorLayer->setDelegate(std::make_unique<CursorDelegateOpenGL>(output));
     } else {
         cursorLayer->setDelegate(std::make_unique<CursorDelegateQPainter>(output));
     }
     cursorLayer->setParent(workspaceLayer);
     cursorLayer->setSuperlayer(workspaceLayer);
 
     // Software cursor is forced for intel devices because there are screen stuttering issues with hardware cursor,
     // possibly a kernel driver bug. Remove the workaround when https://gitlab.freedesktop.org/drm/intel/-/issues/9571 is fixed.
     static bool forceSoftwareCursorIsSet;
     static const bool forceSoftwareCursor = qEnvironmentVariableIntValue("KWIN_FORCE_SW_CURSOR", &forceSoftwareCursorIsSet) == 1
         || (!forceSoftwareCursorIsSet && GLPlatform::instance() && GLPlatform::instance()->isIntel());
 
     auto updateCursorLayer = [this, output, cursorLayer]() {
         const Cursor *cursor = Cursors::self()->currentCursor();
         const QRectF outputLocalRect = output->mapFromGlobal(cursor->geometry());
         const auto outputLayer = m_backend->cursorLayer(output);
         if (!cursor->isOnOutput(output)) {
             if (outputLayer && outputLayer->isEnabled()) {
                 outputLayer->setEnabled(false);
                 output->updateCursorLayer();
             }
             cursorLayer->setVisible(false);
             return true;
         }
         const auto renderHardwareCursor = [&]() {
             if (!outputLayer || forceSoftwareCursor) {
                 return false;
             }
             QRectF nativeCursorRect = output->transform().map(scaledRect(outputLocalRect, output->scale()), output->pixelSize());
             QSize bufferSize(std::ceil(nativeCursorRect.width()), std::ceil(nativeCursorRect.height()));
             if (const auto fixedSize = outputLayer->fixedSize()) {
                 if (fixedSize->width() < bufferSize.width() || fixedSize->height() < bufferSize.height()) {
                     return false;
                 }
                 bufferSize = *fixedSize;
                 nativeCursorRect = output->transform().map(QRectF(outputLocalRect.topLeft() * output->scale(), bufferSize), output->pixelSize());
             }
             outputLayer->setPosition(nativeCursorRect.topLeft());
             outputLayer->setHotspot(output->transform().map(cursor->hotspot() * output->scale(), bufferSize));
             outputLayer->setSize(bufferSize);
             if (auto beginInfo = outputLayer->beginFrame()) {
                 const RenderTarget &renderTarget = beginInfo->renderTarget;
 
                 RenderLayer renderLayer(output->renderLoop());
                 renderLayer.setDelegate(std::make_unique<SceneDelegate>(m_cursorScene.get(), output));
                 renderLayer.setOutputLayer(outputLayer);
 
                 renderLayer.delegate()->prePaint();
                 renderLayer.delegate()->paint(renderTarget, infiniteRegion());
                 renderLayer.delegate()->postPaint();
 
                 if (!outputLayer->endFrame(infiniteRegion(), infiniteRegion())) {
                     return false;
                 }
             } else {
                 return false;
             }
             outputLayer->setEnabled(true);
             return output->updateCursorLayer();
         };
         if (renderHardwareCursor()) {
             cursorLayer->setVisible(false);
             return true;
         } else {
             if (outputLayer && outputLayer->isEnabled()) {
                 outputLayer->setEnabled(false);
                 output->updateCursorLayer();
             }
             cursorLayer->setVisible(cursor->isOnOutput(output));
             cursorLayer->setGeometry(outputLocalRect);
             cursorLayer->addRepaintFull();
             return false;
         }
     };
     auto moveCursorLayer = [this, output, cursorLayer, updateCursorLayer]() {
         const Cursor *cursor = Cursors::self()->currentCursor();
         const QRectF outputLocalRect = output->mapFromGlobal(cursor->geometry());
         const auto outputLayer = m_backend->cursorLayer(output);
         bool hardwareCursor = false;
         if (outputLayer) {
             if (outputLayer->isEnabled()) {
                 const QRectF nativeCursorRect = output->transform()
                                                     .map(QRectF(outputLocalRect.topLeft() * output->scale(), outputLayer->size()), output->pixelSize());
                 outputLayer->setPosition(nativeCursorRect.topLeft());
                 hardwareCursor = output->updateCursorLayer();
             } else if (!cursorLayer->isVisible() && !forceSoftwareCursor) {
                 // this is for the case that the cursor wasn't visible because it was on a different output before
                 hardwareCursor = updateCursorLayer();
             }
         }
         cursorLayer->setVisible(cursor->isOnOutput(output) && !hardwareCursor);
         cursorLayer->setGeometry(outputLocalRect);
         cursorLayer->addRepaintFull();
     };
     updateCursorLayer();
     connect(output, &Output::geometryChanged, cursorLayer, updateCursorLayer);
     connect(Cursors::self(), &Cursors::currentCursorChanged, cursorLayer, updateCursorLayer);
     connect(Cursors::self(), &Cursors::hiddenChanged, cursorLayer, updateCursorLayer);
     connect(Cursors::self(), &Cursors::positionChanged, cursorLayer, moveCursorLayer);
 
     addSuperLayer(workspaceLayer);
 }
 
 void WaylandCompositor::removeOutput(Output *output)
 {
     if (output->isPlaceholder()) {
         return;
     }
     removeSuperLayer(m_superlayers[output->renderLoop()]);
 }
 
 } // namespace KWin
 
 #include "moc_compositor_wayland.cpp"