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#include "qt3dquickwindow.h"
#include <Qt3DQuick/QQmlAspectEngine>
#include <Qt3DRender/qcamera.h>
#include <Qt3DRender/qrenderaspect.h>
#include <Qt3DRender/qframegraph.h>
#include <Qt3DRender/qrendersurfaceselector.h>
#include <Qt3DInput/qinputaspect.h>
#include <Qt3DInput/qinputsettings.h>
#include <Qt3DLogic/qlogicaspect.h>

#include <QQmlContext>

#include <QtGui/qopenglcontext.h>

QT_BEGIN_NAMESPACE

Qt3DQuickWindow::Qt3DQuickWindow(QWindow *parent)
    : QQuickWindow(parent)
    , m_engine(new Qt3DCore::Quick::QQmlAspectEngine)
    , m_renderAspect(new Qt3DRender::QRenderAspect)
    , m_inputAspect(new Qt3DInput::QInputAspect)
    , m_logicAspect(new Qt3DLogic::QLogicAspect)
    , m_initialized(false)
    , m_cameraAspectRatioMode(AutomaticAspectRatio)
{
    setSurfaceType(QSurface::OpenGLSurface);

    resize(1024, 768);

    QSurfaceFormat format;
    if (QOpenGLContext::openGLModuleType() == QOpenGLContext::LibGL) {
        format.setVersion(4, 3);
        format.setProfile(QSurfaceFormat::CoreProfile);
    }
    format.setDepthBufferSize(24);
    format.setSamples(4);
    format.setStencilBufferSize(8);
    setFormat(format);
    create();

    m_engine->aspectEngine()->registerAspect(m_renderAspect);
    m_engine->aspectEngine()->registerAspect(m_inputAspect);
    m_engine->aspectEngine()->registerAspect(m_logicAspect);
}

Qt3DQuickWindow::~Qt3DQuickWindow()
{
}

void Qt3DQuickWindow::registerAspect(Qt3DCore::QAbstractAspect *aspect)
{
    Q_ASSERT(!isVisible());
    m_engine->aspectEngine()->registerAspect(aspect);
}

void Qt3DQuickWindow::registerAspect(const QString &name)
{
    Q_ASSERT(!isVisible());
    m_engine->aspectEngine()->registerAspect(name);
}

void Qt3DQuickWindow::setSource(const QUrl &source)
{
    m_source = source;
}

Qt3DCore::Quick::QQmlAspectEngine *Qt3DQuickWindow::engine() const
{
    return m_engine.data();
}

void Qt3DQuickWindow::setCameraAspectRatioMode(CameraAspectRatioMode mode)
{
    if (m_cameraAspectRatioMode == mode)
        return;

    m_cameraAspectRatioMode = mode;
    setCameraAspectModeHelper();
    emit cameraAspectRatioModeChanged(mode);
}

Qt3DQuickWindow::CameraAspectRatioMode Qt3DQuickWindow::cameraAspectRatioMode() const
{
    return m_cameraAspectRatioMode;
}

void Qt3DQuickWindow::showEvent(QShowEvent *e)
{
    if (!m_initialized) {

        // Connect to the QQmlAspectEngine's statusChanged signal so that when the QML is loaded
        // and th eobjects hav ebeen instantiated, but before we set them on the QAspectEngine we
        // can swoop in and set the window surface and camera on the framegraph and ensure the camera
        // respects the window's aspect ratio
        connect(m_engine.data(), &Qt3DCore::Quick::QQmlAspectEngine::sceneCreated,
                this, &Qt3DQuickWindow::onSceneCreated);

        m_engine->setSource(m_source);

        // Set the QQmlIncubationController on the window
        // to benefit from asynchronous incubation
        m_engine->qmlEngine()->setIncubationController(QQuickWindow::incubationController());

        m_initialized = true;
    }
    QQuickWindow::showEvent(e);
}

void Qt3DQuickWindow::onSceneCreated(QObject *rootObject)
{
    Q_ASSERT(rootObject);

    setWindowSurface(rootObject);

    if (m_cameraAspectRatioMode == AutomaticAspectRatio) {
        // Set aspect ratio of first camera to match the window
        QList<Qt3DRender::QCamera *> cameras
            = rootObject->findChildren<Qt3DRender::QCamera *>();
        if (cameras.isEmpty()) {
            qWarning() << "No camera found";
        } else {
            m_camera = cameras.first();
            setCameraAspectModeHelper();
        }
    }

    // Set ourselves up as a source of input events for the input aspect
    Qt3DInput::QInputSettings *inputSettings = rootObject->findChild<Qt3DInput::QInputSettings *>();
    if (inputSettings) {
        inputSettings->setEventSource(this);
    } else {
        qWarning() << "No Input Settings found, keyboard and mouse events won't be handled";
    }
}

void Qt3DQuickWindow::setWindowSurface(QObject *rootObject)
{
    // Find surface selector in framegraph and set ourselves up as the
    // render surface there
    Qt3DRender::QFrameGraph *frameGraphComponent
        = rootObject->findChild<Qt3DRender::QFrameGraph *>();
    if (!frameGraphComponent) {
        qWarning() << "No frame graph component found";
        return;
    }

    Qt3DCore::QNode *frameGraphRoot = frameGraphComponent->activeFrameGraph();
    if (!frameGraphRoot) {
        qWarning() << "No active frame graph found";
        return;
    }

    Qt3DRender::QRenderSurfaceSelector *surfaceSelector
        = frameGraphRoot->findChild<Qt3DRender::QRenderSurfaceSelector *>();
    if (!surfaceSelector) {
        qWarning() << "No render surface selector found in frame graph";
        return;
    }

    surfaceSelector->setWindow(this);
}

void Qt3DQuickWindow::setCameraAspectModeHelper()
{
    switch (m_cameraAspectRatioMode) {
    case AutomaticAspectRatio:
        connect(this, &QWindow::widthChanged, this, &Qt3DQuickWindow::updateCameraAspectRatio);
        connect(this, &QWindow::heightChanged, this, &Qt3DQuickWindow::updateCameraAspectRatio);
        break;
    case UserAspectRatio:
        disconnect(this, &QWindow::widthChanged, this, &Qt3DQuickWindow::updateCameraAspectRatio);
        disconnect(this, &QWindow::heightChanged, this, &Qt3DQuickWindow::updateCameraAspectRatio);
        break;
    }
}

void Qt3DQuickWindow::updateCameraAspectRatio()
{
    if (m_camera) {
        m_camera->setAspectRatio(static_cast<float>(width()) /
                                 static_cast<float>(height()));
    }
}

QT_END_NAMESPACE