File indexing completed on 2024-05-12 05:31:30

 /*
     KWin - the KDE window manager
     This file is part of the KDE project.
 
     SPDX-FileCopyrightText: 2019 David Edmundson <davidedmundson@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #include "effect/offscreenquickview.h"
 #include "effect/effecthandler.h"
 
 #include "logging_p.h"
 #include "opengl/glutils.h"
 
 #include <QGuiApplication>
 #include <QQmlComponent>
 #include <QQmlContext>
 #include <QQmlEngine>
 #include <QQuickItem>
 #include <QQuickRenderControl>
 #include <QQuickView>
 #include <QStyleHints>
 
 #include <QOffscreenSurface>
 #include <QOpenGLContext>
 #include <QOpenGLFramebufferObject>
 #include <QQuickGraphicsDevice>
 #include <QQuickOpenGLUtils>
 #include <QQuickRenderTarget>
 #include <QTimer>
 #include <private/qeventpoint_p.h> // for QMutableEventPoint
 
 namespace KWin
 {
 
 class Q_DECL_HIDDEN OffscreenQuickView::Private
 {
 public:
     std::unique_ptr<QQuickWindow> m_view;
     std::unique_ptr<QQuickRenderControl> m_renderControl;
     std::unique_ptr<QOffscreenSurface> m_offscreenSurface;
     std::unique_ptr<QOpenGLContext> m_glcontext;
     std::unique_ptr<QOpenGLFramebufferObject> m_fbo;
 
     std::unique_ptr<QTimer> m_repaintTimer;
     QImage m_image;
     std::unique_ptr<GLTexture> m_textureExport;
     // if we should capture a QImage after rendering into our BO.
     // Used for either software QtQuick rendering and nonGL kwin rendering
     bool m_useBlit = false;
     bool m_visible = true;
     bool m_hasAlphaChannel = true;
     bool m_automaticRepaint = true;
 
     QList<QEventPoint> touchPoints;
     QPointingDevice *touchDevice;
 
     ulong lastMousePressTime = 0;
     Qt::MouseButton lastMousePressButton = Qt::NoButton;
 
     void releaseResources();
 
     void updateTouchState(Qt::TouchPointState state, qint32 id, const QPointF &pos);
 };
 
 class Q_DECL_HIDDEN OffscreenQuickScene::Private
 {
 public:
     Private()
     {
     }
 
     std::unique_ptr<QQmlComponent> qmlComponent;
     std::unique_ptr<QQuickItem> quickItem;
 };
 
 OffscreenQuickView::OffscreenQuickView(ExportMode exportMode, bool alpha)
     : d(new OffscreenQuickView::Private)
 {
     d->m_renderControl = std::make_unique<QQuickRenderControl>();
 
     d->m_view = std::make_unique<QQuickWindow>(d->m_renderControl.get());
     Q_ASSERT(d->m_view->setProperty("_KWIN_WINDOW_IS_OFFSCREEN", true) || true);
     d->m_view->setFlags(Qt::FramelessWindowHint);
     d->m_view->setColor(Qt::transparent);
 
     d->m_hasAlphaChannel = alpha;
     if (exportMode == ExportMode::Image) {
         d->m_useBlit = true;
     }
 
     const bool usingGl = d->m_view->rendererInterface()->graphicsApi() == QSGRendererInterface::OpenGL;
 
     if (!usingGl) {
         qCDebug(LIBKWINEFFECTS) << "QtQuick Software rendering mode detected";
         d->m_useBlit = true;
         d->m_renderControl->initialize();
     } else {
         QSurfaceFormat format;
         format.setOption(QSurfaceFormat::ResetNotification);
         format.setDepthBufferSize(16);
         format.setStencilBufferSize(8);
         if (alpha) {
             format.setAlphaBufferSize(8);
         }
 
         d->m_view->setFormat(format);
 
         auto shareContext = QOpenGLContext::globalShareContext();
         d->m_glcontext = std::make_unique<QOpenGLContext>();
         d->m_glcontext->setShareContext(shareContext);
         d->m_glcontext->setFormat(format);
         d->m_glcontext->create();
 
         // and the offscreen surface
         d->m_offscreenSurface = std::make_unique<QOffscreenSurface>();
         d->m_offscreenSurface->setFormat(d->m_glcontext->format());
         d->m_offscreenSurface->create();
 
         d->m_glcontext->makeCurrent(d->m_offscreenSurface.get());
         d->m_view->setGraphicsDevice(QQuickGraphicsDevice::fromOpenGLContext(d->m_glcontext.get()));
         d->m_renderControl->initialize();
         d->m_glcontext->doneCurrent();
 
         // On Wayland, contexts are implicitly shared and QOpenGLContext::globalShareContext() is null.
         if (shareContext && !d->m_glcontext->shareContext()) {
             qCDebug(LIBKWINEFFECTS) << "Failed to create a shared context, falling back to raster rendering";
             // still render via GL, but blit for presentation
             d->m_useBlit = true;
         }
     }
 
     auto updateSize = [this]() {
         contentItem()->setSize(d->m_view->size());
     };
     updateSize();
     connect(d->m_view.get(), &QWindow::widthChanged, this, updateSize);
     connect(d->m_view.get(), &QWindow::heightChanged, this, updateSize);
 
     d->m_repaintTimer = std::make_unique<QTimer>();
     d->m_repaintTimer->setSingleShot(true);
     d->m_repaintTimer->setInterval(10);
 
     connect(d->m_repaintTimer.get(), &QTimer::timeout, this, &OffscreenQuickView::update);
     connect(d->m_renderControl.get(), &QQuickRenderControl::renderRequested, this, &OffscreenQuickView::handleRenderRequested);
     connect(d->m_renderControl.get(), &QQuickRenderControl::sceneChanged, this, &OffscreenQuickView::handleSceneChanged);
 
     d->touchDevice = new QPointingDevice(QStringLiteral("ForwardingTouchDevice"), {}, QInputDevice::DeviceType::TouchScreen, QPointingDevice::PointerType::Finger, QInputDevice::Capability::Position, 10, {});
 }
 
 OffscreenQuickView::~OffscreenQuickView()
 {
     disconnect(d->m_renderControl.get(), &QQuickRenderControl::renderRequested, this, &OffscreenQuickView::handleRenderRequested);
     disconnect(d->m_renderControl.get(), &QQuickRenderControl::sceneChanged, this, &OffscreenQuickView::handleSceneChanged);
 
     if (d->m_glcontext) {
         // close the view whilst we have an active GL context
         d->m_glcontext->makeCurrent(d->m_offscreenSurface.get());
     }
 
     d->m_view.reset();
     d->m_renderControl.reset();
 }
 
 bool OffscreenQuickView::automaticRepaint() const
 {
     return d->m_automaticRepaint;
 }
 
 void OffscreenQuickView::setAutomaticRepaint(bool set)
 {
     if (d->m_automaticRepaint != set) {
         d->m_automaticRepaint = set;
 
         // If there's an in-flight update, disable it.
         if (!d->m_automaticRepaint) {
             d->m_repaintTimer->stop();
         }
     }
 }
 
 void OffscreenQuickView::handleSceneChanged()
 {
     if (d->m_automaticRepaint) {
         d->m_repaintTimer->start();
     }
     Q_EMIT sceneChanged();
 }
 
 void OffscreenQuickView::handleRenderRequested()
 {
     if (d->m_automaticRepaint) {
         d->m_repaintTimer->start();
     }
     Q_EMIT renderRequested();
 }
 
 void OffscreenQuickView::update()
 {
     if (!d->m_visible) {
         return;
     }
     if (d->m_view->size().isEmpty()) {
         return;
     }
 
     bool usingGl = d->m_glcontext != nullptr;
 
     if (usingGl) {
         if (!d->m_glcontext->makeCurrent(d->m_offscreenSurface.get())) {
             // probably a context loss event, kwin is about to reset all the effects anyway
             return;
         }
 
         const QSize nativeSize = d->m_view->size() * d->m_view->devicePixelRatio();
         if (!d->m_fbo || d->m_fbo->size() != nativeSize) {
             d->m_textureExport.reset(nullptr);
 
             QOpenGLFramebufferObjectFormat fboFormat;
             fboFormat.setAttachment(QOpenGLFramebufferObject::CombinedDepthStencil);
             fboFormat.setInternalTextureFormat(GL_RGBA8);
 
             d->m_fbo = std::make_unique<QOpenGLFramebufferObject>(nativeSize, fboFormat);
             if (!d->m_fbo->isValid()) {
                 d->m_fbo.reset();
                 d->m_glcontext->doneCurrent();
                 return;
             }
         }
 
         QQuickRenderTarget renderTarget = QQuickRenderTarget::fromOpenGLTexture(d->m_fbo->texture(), d->m_fbo->size());
         renderTarget.setDevicePixelRatio(d->m_view->devicePixelRatio());
 
         d->m_view->setRenderTarget(renderTarget);
     }
 
     d->m_renderControl->polishItems();
     d->m_renderControl->beginFrame();
     d->m_renderControl->sync();
     d->m_renderControl->render();
     d->m_renderControl->endFrame();
 
     if (usingGl) {
         QQuickOpenGLUtils::resetOpenGLState();
     }
 
     if (d->m_useBlit) {
         if (usingGl) {
             d->m_image = d->m_fbo->toImage();
             d->m_image.setDevicePixelRatio(d->m_view->devicePixelRatio());
         } else {
             d->m_image = d->m_view->grabWindow();
         }
     }
 
     if (usingGl) {
         QOpenGLFramebufferObject::bindDefault();
         d->m_glcontext->doneCurrent();
     }
     Q_EMIT repaintNeeded();
 }
 
 void OffscreenQuickView::forwardMouseEvent(QEvent *e)
 {
     if (!d->m_visible) {
         return;
     }
     switch (e->type()) {
     case QEvent::MouseMove:
     case QEvent::MouseButtonPress:
     case QEvent::MouseButtonRelease: {
         QMouseEvent *me = static_cast<QMouseEvent *>(e);
         const QPoint widgetPos = d->m_view->mapFromGlobal(me->pos());
         QMouseEvent cloneEvent(me->type(), widgetPos, me->pos(), me->button(), me->buttons(), me->modifiers());
         cloneEvent.setAccepted(false);
         QCoreApplication::sendEvent(d->m_view.get(), &cloneEvent);
         e->setAccepted(cloneEvent.isAccepted());
 
         if (e->type() == QEvent::MouseButtonPress) {
             const ulong doubleClickInterval = static_cast<ulong>(QGuiApplication::styleHints()->mouseDoubleClickInterval());
             const bool doubleClick = (me->timestamp() - d->lastMousePressTime < doubleClickInterval) && me->button() == d->lastMousePressButton;
             d->lastMousePressTime = me->timestamp();
             d->lastMousePressButton = me->button();
             if (doubleClick) {
                 d->lastMousePressButton = Qt::NoButton;
                 QMouseEvent doubleClickEvent(QEvent::MouseButtonDblClick, me->localPos(), me->windowPos(), me->screenPos(), me->button(), me->buttons(), me->modifiers());
                 QCoreApplication::sendEvent(d->m_view.get(), &doubleClickEvent);
             }
         }
 
         return;
     }
     case QEvent::HoverEnter:
     case QEvent::HoverLeave:
     case QEvent::HoverMove: {
         QHoverEvent *he = static_cast<QHoverEvent *>(e);
         const QPointF widgetPos = d->m_view->mapFromGlobal(he->pos());
         const QPointF oldWidgetPos = d->m_view->mapFromGlobal(he->oldPos());
         QHoverEvent cloneEvent(he->type(), widgetPos, oldWidgetPos, he->modifiers());
         cloneEvent.setAccepted(false);
         QCoreApplication::sendEvent(d->m_view.get(), &cloneEvent);
         e->setAccepted(cloneEvent.isAccepted());
         return;
     }
     case QEvent::Wheel: {
         QWheelEvent *we = static_cast<QWheelEvent *>(e);
         const QPointF widgetPos = d->m_view->mapFromGlobal(we->position().toPoint());
         QWheelEvent cloneEvent(widgetPos, we->globalPosition(), we->pixelDelta(), we->angleDelta(), we->buttons(),
                                we->modifiers(), we->phase(), we->inverted());
         cloneEvent.setAccepted(false);
         QCoreApplication::sendEvent(d->m_view.get(), &cloneEvent);
         e->setAccepted(cloneEvent.isAccepted());
         return;
     }
     default:
         return;
     }
 }
 
 void OffscreenQuickView::forwardKeyEvent(QKeyEvent *keyEvent)
 {
     if (!d->m_visible) {
         return;
     }
     QCoreApplication::sendEvent(d->m_view.get(), keyEvent);
 }
 
 bool OffscreenQuickView::forwardTouchDown(qint32 id, const QPointF &pos, std::chrono::microseconds time)
 {
     d->updateTouchState(Qt::TouchPointPressed, id, pos);
 
     QTouchEvent event(QEvent::TouchBegin, d->touchDevice, Qt::NoModifier, d->touchPoints);
     event.setTimestamp(std::chrono::duration_cast<std::chrono::milliseconds>(time).count());
     event.setAccepted(false);
     QCoreApplication::sendEvent(d->m_view.get(), &event);
 
     return event.isAccepted();
 }
 
 bool OffscreenQuickView::forwardTouchMotion(qint32 id, const QPointF &pos, std::chrono::microseconds time)
 {
     d->updateTouchState(Qt::TouchPointMoved, id, pos);
 
     QTouchEvent event(QEvent::TouchUpdate, d->touchDevice, Qt::NoModifier, d->touchPoints);
     event.setTimestamp(std::chrono::duration_cast<std::chrono::milliseconds>(time).count());
     event.setAccepted(false);
     QCoreApplication::sendEvent(d->m_view.get(), &event);
 
     return event.isAccepted();
 }
 
 bool OffscreenQuickView::forwardTouchUp(qint32 id, std::chrono::microseconds time)
 {
     d->updateTouchState(Qt::TouchPointReleased, id, QPointF{});
 
     QTouchEvent event(QEvent::TouchEnd, d->touchDevice, Qt::NoModifier, d->touchPoints);
     event.setTimestamp(std::chrono::duration_cast<std::chrono::milliseconds>(time).count());
     event.setAccepted(false);
     QCoreApplication::sendEvent(d->m_view.get(), &event);
 
     return event.isAccepted();
 }
 
 QRect OffscreenQuickView::geometry() const
 {
     return d->m_view->geometry();
 }
 
 void OffscreenQuickView::setOpacity(qreal opacity)
 {
     d->m_view->setOpacity(opacity);
 }
 
 qreal OffscreenQuickView::opacity() const
 {
     return d->m_view->opacity();
 }
 
 bool OffscreenQuickView::hasAlphaChannel() const
 {
     return d->m_hasAlphaChannel;
 }
 
 QQuickItem *OffscreenQuickView::contentItem() const
 {
     return d->m_view->contentItem();
 }
 
 QQuickWindow *OffscreenQuickView::window() const
 {
     return d->m_view.get();
 }
 
 void OffscreenQuickView::setVisible(bool visible)
 {
     if (d->m_visible == visible) {
         return;
     }
     d->m_visible = visible;
 
     if (visible) {
         Q_EMIT d->m_renderControl->renderRequested();
     } else {
         // deferred to not change GL context
         QTimer::singleShot(0, this, [this]() {
             d->releaseResources();
         });
     }
 }
 
 bool OffscreenQuickView::isVisible() const
 {
     return d->m_visible;
 }
 
 void OffscreenQuickView::show()
 {
     setVisible(true);
 }
 
 void OffscreenQuickView::hide()
 {
     setVisible(false);
 }
 
 GLTexture *OffscreenQuickView::bufferAsTexture()
 {
     if (d->m_useBlit) {
         d->m_textureExport = GLTexture::upload(d->m_image);
     } else {
         if (!d->m_fbo) {
             return nullptr;
         }
         if (!d->m_textureExport) {
             d->m_textureExport = GLTexture::createNonOwningWrapper(d->m_fbo->texture(), d->m_fbo->format().internalTextureFormat(), d->m_fbo->size());
         }
     }
     return d->m_textureExport.get();
 }
 
 QImage OffscreenQuickView::bufferAsImage() const
 {
     return d->m_image;
 }
 
 QSize OffscreenQuickView::size() const
 {
     return d->m_view->geometry().size();
 }
 
 void OffscreenQuickView::setGeometry(const QRect &rect)
 {
     const QRect oldGeometry = d->m_view->geometry();
     d->m_view->setGeometry(rect);
     // QWindow::setGeometry() won't sync output if there's no platform window.
     d->m_view->setScreen(QGuiApplication::screenAt(rect.center()));
     Q_EMIT geometryChanged(oldGeometry, rect);
 }
 
 void OffscreenQuickView::Private::releaseResources()
 {
     if (m_glcontext) {
         m_glcontext->makeCurrent(m_offscreenSurface.get());
         m_view->releaseResources();
         m_glcontext->doneCurrent();
     } else {
         m_view->releaseResources();
     }
 }
 
 void OffscreenQuickView::Private::updateTouchState(Qt::TouchPointState state, qint32 id, const QPointF &pos)
 {
     // Remove the points that were previously in a released state, since they
     // are no longer relevant. Additionally, reset the state of all remaining
     // points to Stationary so we only have one touch point with a different
     // state.
     touchPoints.erase(std::remove_if(touchPoints.begin(), touchPoints.end(), [](QTouchEvent::TouchPoint &point) {
                           if (point.state() == QEventPoint::Released) {
                               return true;
                           }
                           QMutableEventPoint::setState(point, QEventPoint::Stationary);
                           return false;
                       }),
                       touchPoints.end());
 
     // QtQuick Pointer Handlers incorrectly consider a touch point with ID 0
     // to be an invalid touch point. This has been fixed in Qt 6 but could not
     // be fixed for Qt 5. Instead, we offset kwin's internal IDs with this
     // offset to trick QtQuick into treating them as valid points.
     static const qint32 idOffset = 111;
 
     // Find the touch point that has changed. This is separate from the above
     // loop because removing the released touch points invalidates iterators.
     auto changed = std::find_if(touchPoints.begin(), touchPoints.end(), [id](const QTouchEvent::TouchPoint &point) {
         return point.id() == id + idOffset;
     });
 
     switch (state) {
     case Qt::TouchPointPressed: {
         if (changed != touchPoints.end()) {
             return;
         }
 
         QTouchEvent::TouchPoint point;
         QMutableEventPoint::setState(point, QEventPoint::Pressed);
         QMutableEventPoint::setId(point, id + idOffset);
         QMutableEventPoint::setGlobalPosition(point, pos);
         QMutableEventPoint::setScenePosition(point, m_view->mapFromGlobal(pos.toPoint()));
         QMutableEventPoint::setPosition(point, m_view->mapFromGlobal(pos.toPoint()));
 
         touchPoints.append(point);
     } break;
     case Qt::TouchPointMoved: {
         if (changed == touchPoints.end()) {
             return;
         }
 
         auto &point = *changed;
         QMutableEventPoint::setGlobalLastPosition(point, point.globalPosition());
         QMutableEventPoint::setState(point, QEventPoint::Updated);
         QMutableEventPoint::setScenePosition(point, m_view->mapFromGlobal(pos.toPoint()));
         QMutableEventPoint::setPosition(point, m_view->mapFromGlobal(pos.toPoint()));
         QMutableEventPoint::setGlobalPosition(point, pos);
     } break;
     case Qt::TouchPointReleased: {
         if (changed == touchPoints.end()) {
             return;
         }
 
         auto &point = *changed;
         QMutableEventPoint::setGlobalLastPosition(point, point.globalPosition());
         QMutableEventPoint::setState(point, QEventPoint::Released);
     } break;
     default:
         break;
     }
 }
 
 OffscreenQuickScene::OffscreenQuickScene(OffscreenQuickView::ExportMode exportMode, bool alpha)
     : OffscreenQuickView(exportMode, alpha)
     , d(new OffscreenQuickScene::Private)
 {
 }
 
 OffscreenQuickScene::~OffscreenQuickScene() = default;
 
 void OffscreenQuickScene::setSource(const QUrl &source)
 {
     setSource(source, QVariantMap());
 }
 
 void OffscreenQuickScene::setSource(const QUrl &source, const QVariantMap &initialProperties)
 {
     if (!d->qmlComponent) {
         d->qmlComponent = std::make_unique<QQmlComponent>(effects->qmlEngine());
     }
 
     d->qmlComponent->loadUrl(source);
     if (d->qmlComponent->isError()) {
         qCWarning(LIBKWINEFFECTS).nospace() << "Failed to load effect quick view " << source << ": " << d->qmlComponent->errors();
         d->qmlComponent.reset();
         return;
     }
 
     d->quickItem.reset();
 
     std::unique_ptr<QObject> qmlObject(d->qmlComponent->createWithInitialProperties(initialProperties));
     QQuickItem *item = qobject_cast<QQuickItem *>(qmlObject.get());
     if (!item) {
         qCWarning(LIBKWINEFFECTS) << "Root object of effect quick view" << source << "is not a QQuickItem";
         return;
     }
 
     qmlObject.release();
     d->quickItem.reset(item);
 
     item->setParentItem(contentItem());
 
     auto updateSize = [item, this]() {
         item->setSize(contentItem()->size());
     };
     updateSize();
     connect(contentItem(), &QQuickItem::widthChanged, item, updateSize);
     connect(contentItem(), &QQuickItem::heightChanged, item, updateSize);
 }
 
 QQuickItem *OffscreenQuickScene::rootItem() const
 {
     return d->quickItem.get();
 }
 
 } // namespace KWin
 
 #include "moc_offscreenquickview.cpp"