Add Manual test for Graphics Frame Capture

Simple window with a rotating rectangle that can be
captured using QGraphicsFrameCapture.

Task-number: QTBUG-116146
Change-Id: Ia3b6928e469d926c53260ee40ed5af97dd280c08
Reviewed-by: Janne Koskinen <janne.p.koskinen@qt.io>

7 files changed, 624 insertions, 0 deletions

diff --git a/tests/manual/CMakeLists.txt b/tests/manual/CMakeLists.txt
index 788a0beb71..af13d736b4 100644
--- a/tests/manual/CMakeLists.txt
+++ b/tests/manual/CMakeLists.txt
@@ -13,6 +13,9 @@ add_subdirectory(filetest)
 # add_subdirectory(embeddedintoforeignwindow)
 # add_subdirectory(foreignwindows)
 add_subdirectory(gestures)
+if (QT_FEATURE_graphicsframecapture)
+    add_subdirectory(graphicsframecapture)
+endif()
 add_subdirectory(highdpi)
 add_subdirectory(inputmethodhints)
 add_subdirectory(keypadnavigation)
diff --git a/tests/manual/graphicsframecapture/CMakeLists.txt b/tests/manual/graphicsframecapture/CMakeLists.txt
new file mode 100644
index 0000000000..8d5fc5952d
--- /dev/null
+++ b/tests/manual/graphicsframecapture/CMakeLists.txt
@@ -0,0 +1,35 @@
+# Copyright (C) 2023 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+#####################################################################
+## graphicsframecapture Binary:
+#####################################################################
+
+qt_internal_add_manual_test(graphicsframecapture
+    SOURCES
+        examplewindow.cpp examplewindow.h
+        main.cpp
+        window.cpp window.h
+    LIBRARIES
+        Qt::Gui
+        Qt::GuiPrivate
+)
+
+# Resources:
+set_source_files_properties("../rhi/shared/color.frag.qsb"
+    PROPERTIES QT_RESOURCE_ALIAS "color.frag.qsb"
+)
+set_source_files_properties("../rhi/shared/color.vert.qsb"
+    PROPERTIES QT_RESOURCE_ALIAS "color.vert.qsb"
+)
+set(graphicsframecapture_resource_files
+    "../rhi/shared/color.frag.qsb"
+    "../rhi/shared/color.vert.qsb"
+)
+
+qt_internal_add_resource(graphicsframecapture "graphicsframecapture"
+    PREFIX
+        "/"
+    FILES
+        ${graphicsframecapture_resource_files}
+)
diff --git a/tests/manual/graphicsframecapture/examplewindow.cpp b/tests/manual/graphicsframecapture/examplewindow.cpp
new file mode 100644
index 0000000000..8a8959541e
--- /dev/null
+++ b/tests/manual/graphicsframecapture/examplewindow.cpp
@@ -0,0 +1,116 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "examplewindow.h"
+#include <QFile>
+#include <rhi/qshader.h>
+
+static float vertexData[] = {
+    // Y up (note clipSpaceCorrMatrix in m_proj), CCW
+     -0.5f,   0.5f,   1.0f, 0.0f, 0.0f,
+     -0.5f,  -0.5f,   1.0f, 0.0f, 0.0f,
+     0.5f,  0.5f,   1.0f, 0.0f, 0.0f,
+
+     0.5f,  0.5f,   1.0f, 0.0f, 0.0f,
+     -0.5f,  -0.5f,   1.0f, 0.0f, 0.0f,
+     0.5f,  -0.5f,   1.0f, 0.0f, 0.0f,
+};
+
+ExampleWindow::ExampleWindow(QRhi::Implementation graphicsApi)
+    : Window(graphicsApi)
+{
+}
+
+QShader ExampleWindow::getShader(const QString &name)
+{
+    QFile f(name);
+    if (f.open(QIODevice::ReadOnly))
+        return QShader::fromSerialized(f.readAll());
+
+    return QShader();
+}
+
+void ExampleWindow::customInit()
+{
+    m_vbuf.reset(m_rhi->newBuffer(QRhiBuffer::Immutable, QRhiBuffer::VertexBuffer, sizeof(vertexData)));
+    m_vbuf->create();
+    m_vbufReady = false;
+
+    m_ubuf.reset(m_rhi->newBuffer(QRhiBuffer::Dynamic, QRhiBuffer::UniformBuffer, 68));
+    m_ubuf->create();
+
+    m_srb.reset(m_rhi->newShaderResourceBindings());
+    m_srb->setBindings({
+            QRhiShaderResourceBinding::uniformBuffer(0, QRhiShaderResourceBinding::VertexStage | QRhiShaderResourceBinding::FragmentStage,
+                                                     m_ubuf.get())
+    });
+    m_srb->create();
+
+    m_ps.reset(m_rhi->newGraphicsPipeline());
+
+    QRhiGraphicsPipeline::TargetBlend premulAlphaBlend;
+    premulAlphaBlend.enable = true;
+    m_ps->setTargetBlends({ premulAlphaBlend });
+
+    const QShader vs = getShader(QLatin1String(":/color.vert.qsb"));
+    if (!vs.isValid())
+        qFatal("Failed to load shader pack (vertex)");
+    const QShader fs = getShader(QLatin1String(":/color.frag.qsb"));
+    if (!fs.isValid())
+        qFatal("Failed to load shader pack (fragment)");
+
+    m_ps->setShaderStages({
+        { QRhiShaderStage::Vertex, vs },
+        { QRhiShaderStage::Fragment, fs }
+    });
+
+    QRhiVertexInputLayout inputLayout;
+    inputLayout.setBindings({
+        { 5 * sizeof(float) }
+    });
+    inputLayout.setAttributes({
+        { 0, 0, QRhiVertexInputAttribute::Float2, 0 },
+        { 0, 1, QRhiVertexInputAttribute::Float3, 2 * sizeof(float) }
+    });
+
+    m_ps->setVertexInputLayout(inputLayout);
+    m_ps->setShaderResourceBindings(m_srb.get());
+    m_ps->setRenderPassDescriptor(m_rp.get());
+
+    m_ps->create();
+}
+
+// called once per frame
+void ExampleWindow::customRender()
+{
+    QRhiResourceUpdateBatch *u = m_rhi->nextResourceUpdateBatch();
+    if (!m_vbufReady) {
+        m_vbufReady = true;
+        u->uploadStaticBuffer(m_vbuf.get(), vertexData);
+    }
+    m_rotation += 1.0f;
+    QMatrix4x4 mvp = m_proj;
+    mvp.rotate(m_rotation, 0, 0, 1);
+    u->updateDynamicBuffer(m_ubuf.get(), 0, 64, mvp.constData());
+    m_opacity += m_opacityDir * 0.005f;
+    if (m_opacity < 0.0f || m_opacity > 1.0f) {
+        m_opacityDir *= -1;
+        m_opacity = qBound(0.0f, m_opacity, 1.0f);
+    }
+    u->updateDynamicBuffer(m_ubuf.get(), 64, 4, &m_opacity);
+
+    QRhiCommandBuffer *cb = m_sc->currentFrameCommandBuffer();
+    const QSize outputSizeInPixels = m_sc->currentPixelSize();
+
+    cb->beginPass(m_sc->currentFrameRenderTarget(), QColor::fromRgbF(0.0f, 0.0f, 0.0f, 1.0f), { 1.0f, 0 }, u);
+
+    cb->setGraphicsPipeline(m_ps.get());
+    cb->setViewport({ 0, 0, float(outputSizeInPixels.width()), float(outputSizeInPixels.height()) });
+    cb->setShaderResources();
+
+    const QRhiCommandBuffer::VertexInput vbufBinding(m_vbuf.get(), 0);
+    cb->setVertexInput(0, 1, &vbufBinding);
+    cb->draw(6);
+
+    cb->endPass();
+}
diff --git a/tests/manual/graphicsframecapture/examplewindow.h b/tests/manual/graphicsframecapture/examplewindow.h
new file mode 100644
index 0000000000..ef0379a82e
--- /dev/null
+++ b/tests/manual/graphicsframecapture/examplewindow.h
@@ -0,0 +1,31 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#ifndef EXAMPLEWINDOW_H
+#define EXAMPLEWINDOW_H
+
+#include "window.h"
+
+class ExampleWindow : public Window
+{
+public:
+    ExampleWindow(QRhi::Implementation graphicsApi);
+
+    void customInit() override;
+    void customRender() override;
+
+private:
+    QShader getShader(const QString &name);
+
+    std::unique_ptr<QRhiBuffer> m_vbuf;
+    bool m_vbufReady = false;
+    std::unique_ptr<QRhiBuffer> m_ubuf;
+    std::unique_ptr<QRhiShaderResourceBindings> m_srb;
+    std::unique_ptr<QRhiGraphicsPipeline> m_ps;
+
+    float m_rotation = 0;
+    float m_opacity = 1;
+    int m_opacityDir = -1;
+};
+
+#endif
diff --git a/tests/manual/graphicsframecapture/main.cpp b/tests/manual/graphicsframecapture/main.cpp
new file mode 100644
index 0000000000..389d0bdc1c
--- /dev/null
+++ b/tests/manual/graphicsframecapture/main.cpp
@@ -0,0 +1,128 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+// This is a compact, minimal demo of deciding the backend at runtime while
+// using the exact same shaders and rendering code without any branching
+// whatsoever once the QWindow is up and the RHI is initialized.
+
+#include <QGuiApplication>
+#include <QCommandLineParser>
+#include "examplewindow.h"
+
+
+QString graphicsApiName(QRhi::Implementation graphicsApi);
+QRhi::Implementation graphicsApiFromCmd(const QGuiApplication &app);
+
+int main(int argc, char **argv)
+{
+    QGuiApplication app(argc, argv);
+    QRhi::Implementation graphicsApi = graphicsApiFromCmd(app);
+
+    QSurfaceFormat fmt;
+    fmt.setDepthBufferSize(24);
+    fmt.setStencilBufferSize(8);
+    QSurfaceFormat::setDefaultFormat(fmt);
+
+    ExampleWindow w(graphicsApi);
+
+#if QT_CONFIG(vulkan)
+    QVulkanInstance inst;
+    if (graphicsApi == QRhi::Vulkan) {
+        inst.setLayers({ "VK_LAYER_KHRONOS_validation" });
+        inst.setExtensions(QRhiVulkanInitParams::preferredInstanceExtensions());
+        if (!inst.create()) {
+            qWarning("Failed to create Vulkan instance, switching to OpenGL");
+            graphicsApi = QRhi::OpenGLES2;
+        }
+    }
+#endif
+
+#if QT_CONFIG(vulkan)
+    if (graphicsApi == QRhi::Vulkan)
+        w.setVulkanInstance(&inst);
+#endif
+    w.resize(1280, 720);
+    w.setTitle(QCoreApplication::applicationName() + QLatin1String(" - ") + graphicsApiName(graphicsApi));
+    w.show();
+
+    int ret = app.exec();
+
+    // Window::event() will not get invoked when the
+    // PlatformSurfaceAboutToBeDestroyed event is sent during the QWindow
+    // destruction. That happens only when exiting via app::quit() instead of
+    // the more common QWindow::close(). Take care of it: if the QPlatformWindow
+    // is still around (there was no close() yet), get rid of the swapchain
+    // while it's not too late.
+    if (w.handle())
+        w.releaseSwapChain();
+
+    return ret;
+}
+
+QString graphicsApiName(QRhi::Implementation graphicsApi)
+{
+    switch (graphicsApi) {
+    case QRhi::Null:
+        return QLatin1String("Null (no output)");
+    case QRhi::OpenGLES2:
+        return QLatin1String("OpenGL 2.x");
+    case QRhi::Vulkan:
+        return QLatin1String("Vulkan");
+    case QRhi::D3D11:
+        return QLatin1String("Direct3D 11");
+    case QRhi::D3D12:
+        return QLatin1String("Direct3D 12");
+    case QRhi::Metal:
+        return QLatin1String("Metal");
+    default:
+        break;
+    }
+    return QString();
+}
+
+QRhi::Implementation graphicsApiFromCmd(const QGuiApplication &app) {
+    QRhi::Implementation graphicsApi;
+#if defined(Q_OS_WIN)
+    graphicsApi = QRhi::D3D11;
+#elif defined(Q_OS_MACOS) || defined(Q_OS_IOS)
+    graphicsApi = QRhi::Metal;
+#elif QT_CONFIG(vulkan)
+    graphicsApi = QRhi::Vulkan;
+#else
+    graphicsApi = QRhi::OpenGLES2;
+#endif
+
+    QCommandLineParser cmdLineParser;
+    cmdLineParser.addHelpOption();
+    QCommandLineOption nullOption({ "n", "null" }, QLatin1String("Null"));
+    cmdLineParser.addOption(nullOption);
+    QCommandLineOption glOption({ "g", "opengl" }, QLatin1String("OpenGL (2.x)"));
+    cmdLineParser.addOption(glOption);
+    QCommandLineOption vkOption({ "v", "vulkan" }, QLatin1String("Vulkan"));
+    cmdLineParser.addOption(vkOption);
+    QCommandLineOption d3d11Option({ "d", "d3d11" }, QLatin1String("Direct3D 11"));
+    cmdLineParser.addOption(d3d11Option);
+    QCommandLineOption d3d12Option({ "D", "d3d12" }, QLatin1String("Direct3D 12"));
+    cmdLineParser.addOption(d3d12Option);
+    QCommandLineOption mtlOption({ "m", "metal" }, QLatin1String("Metal"));
+    cmdLineParser.addOption(mtlOption);
+
+    cmdLineParser.process(app);
+    if (cmdLineParser.isSet(nullOption))
+        graphicsApi = QRhi::Null;
+    if (cmdLineParser.isSet(glOption))
+        graphicsApi = QRhi::OpenGLES2;
+    if (cmdLineParser.isSet(vkOption))
+        graphicsApi = QRhi::Vulkan;
+    if (cmdLineParser.isSet(d3d11Option))
+        graphicsApi = QRhi::D3D11;
+    if (cmdLineParser.isSet(d3d12Option))
+        graphicsApi = QRhi::D3D12;
+    if (cmdLineParser.isSet(mtlOption))
+        graphicsApi = QRhi::Metal;
+
+    qDebug("Selected graphics API is %s", qPrintable(graphicsApiName(graphicsApi)));
+    qDebug("This is a multi-api example, use command line arguments to override:\n%s", qPrintable(cmdLineParser.helpText()));
+
+    return graphicsApi;
+}
diff --git a/tests/manual/graphicsframecapture/window.cpp b/tests/manual/graphicsframecapture/window.cpp
new file mode 100644
index 0000000000..55725958f5
--- /dev/null
+++ b/tests/manual/graphicsframecapture/window.cpp
@@ -0,0 +1,256 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include "window.h"
+#include <QPlatformSurfaceEvent>
+#include <QTimer>
+
+Window::Window(QRhi::Implementation graphicsApi)
+    : m_graphicsApi(graphicsApi)
+{
+    m_capturer.reset(new QGraphicsFrameCapture);
+#if defined(Q_OS_MACOS) || defined(Q_OS_IOS)
+    qDebug("This example uses Metal Capture Manager In App API to capture frames. Press F9 to capture a frame and F10 to open it for analysis");
+#else
+    qDebug("This example uses RenderDoc In App API to capture frames. Press F9 to capture a frame and F10 to open it for analysis");
+    qDebug("On Linux with OpenGL, make sure that librenderdoc.so is loaded using LD_PRELOAD");
+#endif
+    qDebug("The Frame Capturer API will save captures in this directory : %s", qPrintable(m_capturer->capturePath()));
+
+    switch (graphicsApi) {
+    case QRhi::OpenGLES2:
+        setSurfaceType(OpenGLSurface);
+        break;
+    case QRhi::Vulkan:
+        setSurfaceType(VulkanSurface);
+        break;
+    case QRhi::D3D11:
+    case QRhi::D3D12:
+        setSurfaceType(Direct3DSurface);
+        break;
+    case QRhi::Metal:
+        setSurfaceType(MetalSurface);
+        break;
+    default:
+        break;
+    }
+}
+
+void Window::exposeEvent(QExposeEvent *)
+{
+    // initialize and start rendering when the window becomes usable for graphics purposes
+    if (isExposed() && !m_running) {
+        qDebug("init");
+        m_running = true;
+        init();
+        resizeSwapChain();
+    }
+
+    const QSize surfaceSize = m_hasSwapChain ? m_sc->surfacePixelSize() : QSize();
+
+    // stop pushing frames when not exposed (or size is 0)
+    if ((!isExposed() || (m_hasSwapChain && surfaceSize.isEmpty())) && m_running && !m_notExposed) {
+        qDebug("not exposed");
+        m_notExposed = true;
+    }
+
+    // Continue when exposed again and the surface has a valid size. Note that
+    // surfaceSize can be (0, 0) even though size() reports a valid one, hence
+    // trusting surfacePixelSize() and not QWindow.
+    if (isExposed() && m_running && m_notExposed && !surfaceSize.isEmpty()) {
+        qDebug("exposed again");
+        m_notExposed = false;
+        m_newlyExposed = true;
+    }
+
+    // always render a frame on exposeEvent() (when exposed) in order to update
+    // immediately on window resize.
+    if (isExposed() && !surfaceSize.isEmpty())
+        render();
+}
+
+bool Window::event(QEvent *e)
+{
+
+    switch (e->type()) {
+    case QEvent::UpdateRequest:
+        render();
+        break;
+
+    case QEvent::PlatformSurface:
+        // this is the proper time to tear down the swapchain (while the native window and surface are still around)
+        if (static_cast<QPlatformSurfaceEvent *>(e)->surfaceEventType() == QPlatformSurfaceEvent::SurfaceAboutToBeDestroyed)
+            releaseSwapChain();
+        break;
+
+    case QEvent::KeyRelease:
+        if (static_cast<QKeyEvent *>(e)->key() == Qt::Key::Key_F9 && !static_cast<QKeyEvent *>(e)->isAutoRepeat()) {
+            m_shouldCapture = true;
+            return true;
+        }
+        else if (static_cast<QKeyEvent *>(e)->key() == Qt::Key::Key_F10 && !static_cast<QKeyEvent *>(e)->isAutoRepeat()) {
+            if (!m_capturer.isNull())
+                m_capturer->openCapture();
+        }
+        break;
+
+    default:
+        break;
+    }
+
+    return QWindow::event(e);
+
+}
+
+void Window::init()
+{
+    QRhi::Flags rhiFlags = QRhi::EnableDebugMarkers;
+
+    if (m_graphicsApi == QRhi::Null) {
+        QRhiNullInitParams params;
+        m_rhi.reset(QRhi::create(QRhi::Null, &params, rhiFlags));
+    }
+
+#if QT_CONFIG(opengl)
+    if (m_graphicsApi == QRhi::OpenGLES2) {
+        m_fallbackSurface.reset(QRhiGles2InitParams::newFallbackSurface());
+        QRhiGles2InitParams params;
+        params.fallbackSurface = m_fallbackSurface.get();
+        params.window = this;
+        m_rhi.reset(QRhi::create(QRhi::OpenGLES2, &params, rhiFlags));
+    }
+#endif
+
+#if QT_CONFIG(vulkan)
+    if (m_graphicsApi == QRhi::Vulkan) {
+        QRhiVulkanInitParams params;
+        params.inst = vulkanInstance();
+        params.window = this;
+        m_rhi.reset(QRhi::create(QRhi::Vulkan, &params, rhiFlags));
+    }
+#endif
+
+#ifdef Q_OS_WIN
+    if (m_graphicsApi == QRhi::D3D11) {
+        QRhiD3D11InitParams params;
+        params.enableDebugLayer = true;
+        m_rhi.reset(QRhi::create(QRhi::D3D11, &params, rhiFlags));
+    } else if (m_graphicsApi == QRhi::D3D12) {
+        QRhiD3D12InitParams params;
+        params.enableDebugLayer = true;
+        m_rhi.reset(QRhi::create(QRhi::D3D12, &params, rhiFlags));
+    }
+#endif
+
+#if defined(Q_OS_MACOS) || defined(Q_OS_IOS)
+    if (m_graphicsApi == QRhi::Metal) {
+        QRhiMetalInitParams params;
+        m_rhi.reset(QRhi::create(QRhi::Metal, &params, rhiFlags));
+    }
+#endif
+
+    if (!m_rhi)
+        qFatal("Failed to create RHI backend");
+
+    m_sc.reset(m_rhi->newSwapChain());
+    m_ds.reset(m_rhi->newRenderBuffer(QRhiRenderBuffer::DepthStencil,
+                                      QSize(), // no need to set the size here, due to UsedWithSwapChainOnly
+                                      1,
+                                      QRhiRenderBuffer::UsedWithSwapChainOnly));
+    m_sc->setWindow(this);
+    m_sc->setDepthStencil(m_ds.get());
+    m_rp.reset(m_sc->newCompatibleRenderPassDescriptor());
+    m_sc->setRenderPassDescriptor(m_rp.get());
+
+    m_capturer->setRhi(m_rhi.get());
+
+    customInit();
+}
+
+void Window::resizeSwapChain()
+{
+    m_hasSwapChain = m_sc->createOrResize(); // also handles m_ds
+
+    const QSize outputSize = m_sc->currentPixelSize();
+    m_proj = m_rhi->clipSpaceCorrMatrix();
+    m_proj.perspective(45.0f, outputSize.width() / (float) outputSize.height(), 0.01f, 1000.0f);
+    m_proj.translate(0, 0, -4);
+}
+
+void Window::releaseSwapChain()
+{
+    if (m_hasSwapChain) {
+        m_hasSwapChain = false;
+        m_sc->destroy();
+    }
+}
+
+void Window::render()
+{
+    if (!m_hasSwapChain || m_notExposed)
+        return;
+
+    // If the window got resized or newly exposed, resize the swapchain. (the
+    // newly-exposed case is not actually required by some platforms, but
+    // f.ex. Vulkan on Windows seems to need it)
+    //
+    // This (exposeEvent + the logic here) is the only safe way to perform
+    // resize handling. Note the usage of the RHI's surfacePixelSize(), and
+    // never QWindow::size(). (the two may or may not be the same under the hood,
+    // depending on the backend and platform)
+    //
+    if (m_sc->currentPixelSize() != m_sc->surfacePixelSize() || m_newlyExposed) {
+        resizeSwapChain();
+        if (!m_hasSwapChain)
+            return;
+        m_newlyExposed = false;
+    }
+
+    if (m_shouldCapture)
+        m_capturer->startCaptureFrame();
+
+    QRhi::FrameOpResult r = m_rhi->beginFrame(m_sc.get());
+    if (r == QRhi::FrameOpSwapChainOutOfDate) {
+        resizeSwapChain();
+        if (!m_hasSwapChain)
+            return;
+        r = m_rhi->beginFrame(m_sc.get());
+    }
+    if (r != QRhi::FrameOpSuccess) {
+        qDebug("beginFrame failed with %d, retry", r);
+        requestUpdate();
+        return;
+    }
+
+    customRender();
+
+    m_rhi->endFrame(m_sc.get());
+
+    if (m_shouldCapture) {
+        m_capturer->endCaptureFrame();
+        m_shouldCapture = false;
+    }
+
+// Always request the next frame via requestUpdate(). On some platforms this is backed
+// by a platform-specific solution, e.g. CVDisplayLink on macOS, which is potentially
+// more efficient than a timer, queued metacalls, etc.
+//
+// However, the rendering behavior is identical no matter how the next round of
+// rendering is triggered: the rendering thread is throttled to the presentation rate
+// (either in beginFrame() or endFrame()) so the triangle should rotate at the exact
+// same speed no matter which approach is taken here.
+
+#if 1
+    requestUpdate();
+#else
+    QTimer::singleShot(0, this, [this] { render(); });
+#endif
+}
+
+void Window::customInit()
+{
+}
+
+void Window::customRender()
+{
+}
diff --git a/tests/manual/graphicsframecapture/window.h b/tests/manual/graphicsframecapture/window.h
new file mode 100644
index 0000000000..faacdabfc1
--- /dev/null
+++ b/tests/manual/graphicsframecapture/window.h
@@ -0,0 +1,55 @@
+// Copyright (C) 2023 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#ifndef WINDOW_H
+#define WINDOW_H
+
+#include <QWindow>
+#include <QOffscreenSurface>
+#include <rhi/qrhi.h>
+#include <QtGui/private/qgraphicsframecapture_p.h>
+
+class Window : public QWindow
+{
+public:
+    Window(QRhi::Implementation graphicsApi);
+
+    void releaseSwapChain();
+
+protected:
+    virtual void customInit();
+    virtual void customRender();
+
+    // destruction order matters to a certain degree: the fallbackSurface must
+    // outlive the rhi, the rhi must outlive all other resources.  The resources
+    // need no special order when destroying.
+#if QT_CONFIG(opengl)
+    std::unique_ptr<QOffscreenSurface> m_fallbackSurface;
+#endif
+    std::unique_ptr<QRhi> m_rhi;
+    std::unique_ptr<QRhiSwapChain> m_sc;
+    std::unique_ptr<QRhiRenderBuffer> m_ds;
+    std::unique_ptr<QRhiRenderPassDescriptor> m_rp;
+
+    bool m_hasSwapChain = false;
+    QMatrix4x4 m_proj;
+
+private:
+    void init();
+    void resizeSwapChain();
+    void render();
+
+    void exposeEvent(QExposeEvent *) override;
+    bool event(QEvent *) override;
+
+    QRhi::Implementation m_graphicsApi;
+
+    bool m_running = false;
+    bool m_notExposed = false;
+    bool m_newlyExposed = false;
+
+    QScopedPointer<QGraphicsFrameCapture> m_capturer;
+    bool m_shouldCapture = false;
+};
+
+#endif