Add wip-cpp-compositor to manual tests

This is an example similar to minimal-cpp, but for xdg-shell instead of
ivi-application. Eventually it should replace qwindow-compositor as the
main c++-only example compositor.

Task-number: QTBUG-69937
Change-Id: Icac70e4af8f97c5f628d7e30279249210772a1c1
Reviewed-by: Paul Olav Tvete <paul.tvete@qt.io>

7 files changed, 767 insertions, 0 deletions

diff --git a/tests/manual/wip-cpp-compositor/README.md b/tests/manual/wip-cpp-compositor/README.md
new file mode 100644
index 000000000..f5af93a71
--- /dev/null
+++ b/tests/manual/wip-cpp-compositor/README.md
@@ -0,0 +1,6 @@
+# Reference C++ Compositor
+
+An example showing what is required to get a C++-based compositor up and
+running implementing basic functionality such as pointer and keyboard input as
+well as resizing and moving windows. This example uses the stable xdg-shell
+protocol.
diff --git a/tests/manual/wip-cpp-compositor/compositor.cpp b/tests/manual/wip-cpp-compositor/compositor.cpp
new file mode 100644
index 000000000..d65c5f0c3
--- /dev/null
+++ b/tests/manual/wip-cpp-compositor/compositor.cpp
@@ -0,0 +1,290 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of the Qt Wayland module
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "compositor.h"
+#include "window.h"
+
+#include <QtWaylandCompositor/QWaylandOutput>
+#include <QtWaylandCompositor/QWaylandXdgShell>
+#include <QtWaylandCompositor/QWaylandSeat>
+
+#include <QOpenGLFunctions>
+
+QOpenGLTexture *View::getTexture() {
+    if (advance())
+        m_texture = currentBuffer().toOpenGLTexture();
+    return m_texture;
+}
+
+void View::setGlobalPosition(const QPoint &position)
+{
+    if (m_globalPosition == position)
+        return;
+
+    m_globalPosition = position;
+    emit globalPositionChanged();
+}
+
+QPoint View::mapToLocal(const QPoint &globalPosition) const
+{
+    return globalPosition - this->globalPosition();
+}
+
+void View::updateAnchoredPosition()
+{
+    QPoint offset;
+    QSize size = surface()->size();
+    QSize delta = size - m_lastSize;
+    if (m_anchorEdges & Qt::RightEdge)
+        offset.setX(-delta.width());
+    if (m_anchorEdges & Qt::BottomEdge)
+        offset.setY(-delta.height());
+    setGlobalPosition(globalPosition() + offset);
+    m_lastSize = size;
+}
+
+void View::handleResizeMove(const QPoint &delta)
+{
+    Q_UNUSED(delta);
+    qWarning() << "Resize not implemented for this view";
+}
+
+ToplevelView::ToplevelView(QWaylandXdgToplevel *toplevel)
+    : m_toplevel(toplevel)
+{
+    QWaylandXdgSurface *xdgSurface = toplevel->xdgSurface();
+    setSurface(xdgSurface->surface());
+    connect(toplevel, &QWaylandXdgToplevel::startMove, this, &View::startMove);
+    connect(toplevel, &QWaylandXdgToplevel::startResize, this, [this](QWaylandSeat *, Qt::Edges edges) {
+        m_resize.edges = edges;
+        m_resize.initialSize = m_toplevel->xdgSurface()->windowGeometry().size();
+        Qt::Edges opposite = edges ^ Qt::Edges(0b1111);
+        setAnchorEdges(opposite);
+        emit startResize();
+    });
+    QVector<QWaylandXdgToplevel::State> states{QWaylandXdgToplevel::ActivatedState};
+    toplevel->sendConfigure(QSize(0, 0), states);
+}
+
+void ToplevelView::handleResizeMove(const QPoint &delta)
+{
+    QSize newSize = m_toplevel->sizeForResize(m_resize.initialSize, delta, m_resize.edges);
+    m_toplevel->sendResizing(newSize);
+}
+
+void ToplevelView::handleResizeRelease()
+{
+    setAnchorEdges({});
+    m_resize.edges = {};
+    m_resize.initialSize = {};
+}
+
+Compositor::~Compositor()
+{
+    delete m_xdgShell;
+}
+
+void Compositor::create()
+{
+    QWaylandCompositor::create();
+
+    m_xdgShell = new QWaylandXdgShell(this);
+    connect(m_xdgShell, &QWaylandXdgShell::toplevelCreated, this, &Compositor::handleXdgToplevelCreated);
+}
+
+View *Compositor::viewAt(const QPoint &position)
+{
+    // Since views are stored in painting order (back to front), we have to iterate backwards
+    // to find the topmost view at the given point
+    for (auto it = m_views.crbegin(); it != m_views.crend(); ++it) {
+        View *view = *it;
+        if (view->globalGeometry().contains(position))
+            return view;
+    }
+    return nullptr;
+}
+
+void Compositor::raise(View *view)
+{
+    m_views.removeAll(view);
+    m_views << view;
+    defaultSeat()->setKeyboardFocus(view->surface());
+    triggerRender();
+}
+
+void Compositor::handleMousePress(const QPoint &position, Qt::MouseButton button)
+{
+    if (m_grab.state == Grab::None) {
+        m_grab.view = viewAt(position);
+        if (m_grab.view) {
+            m_grab.state = Grab::Input;
+            m_grab.startGlobalPosition = position;
+            m_grab.startLocalPosition = m_grab.view->mapToLocal(position);
+            raise(m_grab.view);
+        }
+    }
+
+    switch (m_grab.state) {
+    case Grab::Input: {
+        auto *seat = defaultSeat();
+        seat->sendMouseMoveEvent(m_grab.view, m_grab.view->mapToLocal(position));
+        seat->sendMousePressEvent(button);
+        break;
+    }
+    case Grab::Move:
+    case Grab::Resize:
+    case Grab::None:
+        break;
+    }
+}
+
+void Compositor::handleMouseRelease(const QPoint &position, Qt::MouseButton button, Qt::MouseButtons buttons)
+{
+    auto *seat = defaultSeat();
+
+    switch (m_grab.state) {
+    case Grab::Input:
+        seat->sendMouseMoveEvent(m_grab.view, m_grab.view->mapToLocal(position));
+        seat->sendMouseReleaseEvent(button);
+        if (buttons == Qt::NoButton) {
+            View *newView = viewAt(position);
+            if (newView != m_grab.view) {
+                seat->setMouseFocus(newView);
+                if (newView)
+                    seat->sendMouseMoveEvent(newView, newView->mapToLocal(position));
+            }
+            m_grab.view = nullptr;
+            m_grab.state = Grab::None;
+        }
+        break;
+    case Grab::Move:
+    case Grab::Resize:
+        m_grab.state = Grab::None;
+        m_grab.view = nullptr;
+        if (View *view = viewAt(position))
+            seat->sendMouseMoveEvent(view, view->mapToLocal(position));
+        break;
+    case Grab::None:
+        if (View *view = viewAt(position))
+            seat->sendMouseMoveEvent(view, view->mapToLocal(position));
+        break;
+    }
+}
+
+void Compositor::handleMouseMove(const QPoint &position)
+{
+    switch (m_grab.state) {
+    case Grab::Input:
+        defaultSeat()->sendMouseMoveEvent(m_grab.view, m_grab.view->mapToLocal(position));
+        break;
+    case Grab::None:
+        if (View *view = viewAt(position))
+            defaultSeat()->sendMouseMoveEvent(view, view->mapToLocal(position));
+        break;
+    case Grab::Resize:
+        m_grab.view->handleResizeMove(position - m_grab.startGlobalPosition);
+        break;
+    case Grab::Move:
+        m_grab.view->setGlobalPosition(position - m_grab.startLocalPosition);
+        break;
+    }
+}
+
+void Compositor::handleMouseWheel(Qt::Orientation orientation, int delta)
+{
+    defaultSeat()->sendMouseWheelEvent(orientation, delta);
+}
+
+void Compositor::handleKeyPress(quint32 nativeScanCode)
+{
+    defaultSeat()->sendKeyPressEvent(nativeScanCode);
+}
+
+void Compositor::handleKeyRelease(quint32 nativeScanCode)
+{
+    defaultSeat()->sendKeyReleaseEvent(nativeScanCode);
+}
+
+void Compositor::handleXdgToplevelCreated(QWaylandXdgToplevel *toplevel, QWaylandXdgSurface *xdgSurface)
+{
+    Q_UNUSED(xdgSurface);
+    auto *view = new ToplevelView(toplevel);
+    addView(view);
+}
+
+void Compositor::addView(View *view)
+{
+    view->setOutput(outputFor(m_window));
+    m_views << view;
+    connect(view, &QWaylandView::surfaceDestroyed, this, &Compositor::handleViewSurfaceDestroyed);
+    connect(view, &View::globalPositionChanged, this, &Compositor::triggerRender);
+    connect(view->surface(), &QWaylandSurface::redraw, this, &Compositor::triggerRender);
+    connect(view, &View::startMove, this, [this, view](){
+        m_grab.view = view;
+        m_grab.state = Grab::Move;
+    });
+    connect(view, &View::startResize, this, [this, view]() {
+        m_grab.view = view;
+        m_grab.state = Grab::Resize;
+    });
+}
+
+void Compositor::handleViewSurfaceDestroyed()
+{
+    auto *view = qobject_cast<ToplevelView*>(sender());
+    m_views.removeAll(view);
+    delete view;
+    triggerRender();
+}
+
+void Compositor::triggerRender()
+{
+    m_window->requestUpdate();
+}
diff --git a/tests/manual/wip-cpp-compositor/compositor.h b/tests/manual/wip-cpp-compositor/compositor.h
new file mode 100644
index 000000000..5c2d6a2f5
--- /dev/null
+++ b/tests/manual/wip-cpp-compositor/compositor.h
@@ -0,0 +1,160 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of the Qt Wayland module
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef COMPOSITOR_H
+#define COMPOSITOR_H
+
+#include <QtCore/QPointer>
+
+#include <QtWaylandCompositor/QWaylandCompositor>
+#include <QtWaylandCompositor/QWaylandSurface>
+#include <QtWaylandCompositor/QWaylandView>
+
+QT_BEGIN_NAMESPACE
+
+class Window;
+class QOpenGLTexture;
+class QWaylandXdgShell;
+class QWaylandXdgSurface;
+class QWaylandXdgToplevel;
+
+class View : public QWaylandView
+{
+    Q_OBJECT
+public:
+    explicit View() = default;
+    QOpenGLTexture *getTexture();
+    QSize size() const { return surface() ? surface()->size() : QSize(); }
+    QRect globalGeometry() const { return {globalPosition(), surface()->size()}; }
+    QPoint globalPosition() const { return m_globalPosition; }
+    void setGlobalPosition(const QPoint &position);
+    QPoint mapToLocal(const QPoint &globalPosition) const;
+    void setAnchorEdges(Qt::Edges edges) { m_anchorEdges = edges; }
+    void updateAnchoredPosition();
+
+    virtual void handleResizeMove(const QPoint &delta);
+    virtual void handleResizeRelease() {}
+
+signals:
+    void globalPositionChanged();
+    void startResize();
+    void startMove();
+
+private:
+    QOpenGLTexture *m_texture = nullptr;
+    QPoint m_globalPosition;
+    Qt::Edges m_anchorEdges;
+    QSize m_lastSize;
+};
+
+class ToplevelView : public View
+{
+    Q_OBJECT
+public:
+    explicit ToplevelView(QWaylandXdgToplevel *toplevel);
+    void handleResizeMove(const QPoint &delta) override;
+    void handleResizeRelease() override;
+
+private:
+    QWaylandXdgToplevel *m_toplevel = nullptr;
+    struct Resize  {
+        QSize initialSize;
+        Qt::Edges edges;
+    } m_resize;
+};
+
+class Compositor : public QWaylandCompositor
+{
+    Q_OBJECT
+public:
+    explicit Compositor() = default;
+    ~Compositor() override;
+    void create() override;
+    void setWindow(Window *window) { m_window = window; }
+
+    QList<View *> views() const { return m_views; }
+    View *viewAt(const QPoint &position);
+
+    void raise(View *view);
+
+    void handleGlInitialized() { create(); }
+    void handleMousePress(const QPoint &position, Qt::MouseButton button);
+    void handleMouseRelease(const QPoint &position, Qt::MouseButton button, Qt::MouseButtons buttons);
+    void handleMouseMove(const QPoint &position);
+    void handleMouseWheel(Qt::Orientation orientation, int delta);
+
+    void handleKeyPress(quint32 nativeScanCode);
+    void handleKeyRelease(quint32 nativeScanCode);
+
+signals:
+    void startMove();
+
+private slots:
+    void handleXdgToplevelCreated(QWaylandXdgToplevel *toplevel, QWaylandXdgSurface *xdgSurface);
+    void addView(View *view);
+    void handleViewSurfaceDestroyed();
+    void triggerRender();
+
+private:
+    Window *m_window = nullptr;
+    QWaylandXdgShell *m_xdgShell = nullptr;
+    QList<View *> m_views; // Sorted by painters algorithm (back to front)
+    struct Grab {
+        QPointer<View> view;
+        enum State { None, Input, Move, Resize };
+        State state = None;
+        QPoint startLocalPosition; // in View's coordinate system
+        QPoint startGlobalPosition;
+    } m_grab;
+};
+
+QT_END_NAMESPACE
+
+#endif // COMPOSITOR_H
diff --git a/tests/manual/wip-cpp-compositor/main.cpp b/tests/manual/wip-cpp-compositor/main.cpp
new file mode 100644
index 000000000..8ca5a6f33
--- /dev/null
+++ b/tests/manual/wip-cpp-compositor/main.cpp
@@ -0,0 +1,67 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of the Qt Wayland module
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QGuiApplication>
+#include "window.h"
+#include "compositor.h"
+
+int main(int argc, char *argv[])
+{
+    QGuiApplication app(argc, argv);
+
+    Compositor compositor;
+    Window window(&compositor);
+    compositor.setWindow(&window);
+
+    window.resize(800, 600);
+    window.show();
+
+    return app.exec();
+}
diff --git a/tests/manual/wip-cpp-compositor/window.cpp b/tests/manual/wip-cpp-compositor/window.cpp
new file mode 100644
index 000000000..b5b2581e0
--- /dev/null
+++ b/tests/manual/wip-cpp-compositor/window.cpp
@@ -0,0 +1,145 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of the Qt Wayland module
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "window.h"
+#include "compositor.h"
+
+#include <QPainter>
+#include <QMatrix4x4>
+#include <QOpenGLFunctions>
+#include <QOpenGLTexture>
+#include <QMouseEvent>
+
+Window::Window(Compositor *compositor)
+    : m_compositor(compositor)
+    , m_output(new QWaylandOutput(compositor, this))
+{
+    m_output->setSizeFollowsWindow(true);
+}
+
+void Window::initializeGL()
+{
+    m_textureBlitter.create();
+    m_compositor->handleGlInitialized();
+}
+
+void Window::paintGL()
+{
+    m_output->frameStarted();
+
+    QOpenGLFunctions *functions = context()->functions();
+    functions->glClearColor(.4f, .7f, .1f, 0.5f);
+    functions->glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+    GLenum currentTarget = GL_TEXTURE_2D;
+    m_textureBlitter.bind(currentTarget);
+    functions->glEnable(GL_BLEND);
+    functions->glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+    const auto views = m_compositor->views();
+
+    for (View *view : views) {
+        auto *texture = view->getTexture();
+        if (!texture)
+            continue;
+        if (texture->target() != currentTarget) {
+            currentTarget = texture->target();
+            m_textureBlitter.bind(currentTarget);
+        }
+        GLuint textureId = texture->textureId();
+
+        // Anchored position needs to be updated immediately before rendering or
+        // position and size might get out of sync.
+        view->updateAnchoredPosition();
+
+        QWaylandSurface *surface = view->surface();
+        if (surface && surface->hasContent()) {
+            QOpenGLTextureBlitter::Origin surfaceOrigin =
+                    view->currentBuffer().origin() == QWaylandSurface::OriginTopLeft
+                    ? QOpenGLTextureBlitter::OriginTopLeft
+                    : QOpenGLTextureBlitter::OriginBottomLeft;
+            QMatrix4x4 targetTransform = QOpenGLTextureBlitter::targetTransform(view->globalGeometry(), QRect(QPoint(), size()));
+            m_textureBlitter.blit(textureId, targetTransform, surfaceOrigin);
+        }
+    }
+    m_textureBlitter.release();
+
+    m_output->sendFrameCallbacks();
+}
+
+void Window::mousePressEvent(QMouseEvent *event)
+{
+    m_compositor->handleMousePress(event->localPos().toPoint(), event->button());
+}
+
+void Window::mouseReleaseEvent(QMouseEvent *event)
+{
+    m_compositor->handleMouseRelease(event->localPos().toPoint(), event->button(), event->buttons());
+}
+
+void Window::mouseMoveEvent(QMouseEvent *event)
+{
+    m_compositor->handleMouseMove(event->localPos().toPoint());
+}
+
+void Window::wheelEvent(QWheelEvent *event)
+{
+    m_compositor->handleMouseWheel(event->orientation(), event->delta());
+}
+
+void Window::keyPressEvent(QKeyEvent *event)
+{
+    m_compositor->handleKeyPress(event->nativeScanCode());
+}
+
+void Window::keyReleaseEvent(QKeyEvent *event)
+{
+    m_compositor->handleKeyRelease(event->nativeScanCode());
+}
diff --git a/tests/manual/wip-cpp-compositor/window.h b/tests/manual/wip-cpp-compositor/window.h
new file mode 100644
index 000000000..bc71207ee
--- /dev/null
+++ b/tests/manual/wip-cpp-compositor/window.h
@@ -0,0 +1,87 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the examples of the Qt Wayland module
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef WINDOW_H
+#define WINDOW_H
+
+#include <QOpenGLWindow>
+#include <QOpenGLTextureBlitter>
+
+QT_BEGIN_NAMESPACE
+
+class Compositor;
+class QWaylandOutput;
+
+class Window : public QOpenGLWindow
+{
+public:
+    explicit Window(Compositor *compositor);
+
+protected:
+    void initializeGL() override;
+    void paintGL() override;
+
+    void mousePressEvent(QMouseEvent *event) override;
+    void mouseReleaseEvent(QMouseEvent *event) override;
+    void mouseMoveEvent(QMouseEvent *event) override;
+    void wheelEvent(QWheelEvent *event) override;
+
+    void keyPressEvent(QKeyEvent *event) override;
+    void keyReleaseEvent(QKeyEvent *event) override;
+
+private:
+    QOpenGLTextureBlitter m_textureBlitter;
+    Compositor *m_compositor = nullptr;
+    QWaylandOutput *m_output = nullptr;
+};
+
+QT_END_NAMESPACE
+
+#endif //WINDOW_H
diff --git a/tests/manual/wip-cpp-compositor/wip-cpp-compositor.pro b/tests/manual/wip-cpp-compositor/wip-cpp-compositor.pro
new file mode 100644
index 000000000..546842acb
--- /dev/null
+++ b/tests/manual/wip-cpp-compositor/wip-cpp-compositor.pro
@@ -0,0 +1,12 @@
+QT += gui waylandcompositor
+
+HEADERS += \
+    compositor.h \
+    window.h
+
+SOURCES += main.cpp \
+    compositor.cpp \
+    window.cpp
+
+target.path = $$[QT_INSTALL_EXAMPLES]/wayland/reference-cpp
+INSTALLS += target