- Qt 5.5
- Qt3D Module
- Qt3D: Dynamic Scene C++ Example
- examplescene.cpp Example File
- Qt 5.5.1 Reference Documentation

# examplescene.cpp Example File

dynamicscene-cpp/examplescene.cpp

    /****************************************************************************
    **
    ** Copyright (C) 2015 Klaralvdalens Datakonsult AB (KDAB).
    ** Contact: http://www.qt-project.org/legal
    **
    ** This file is part of the Qt3D module of the Qt Toolkit.
    **
    ** $QT_BEGIN_LICENSE:LGPL3$
    ** 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 http://www.qt.io/terms-conditions. For further
    ** information use the contact form at http://www.qt.io/contact-us.
    **
    ** GNU Lesser General Public License Usage
    ** Alternatively, this file may be used under the terms of the GNU Lesser
    ** General Public License version 3 as published by the Free Software
    ** Foundation and appearing in the file LICENSE.LGPLv3 included in the
    ** packaging of this file. Please review the following information to
    ** ensure the GNU Lesser General Public License version 3 requirements
    ** will be met: https://www.gnu.org/licenses/lgpl.html.
    **
    ** GNU General Public License Usage
    ** Alternatively, this file may be used under the terms of the GNU
    ** General Public License version 2.0 or later as published by the Free
    ** Software Foundation and appearing in the file LICENSE.GPL included in
    ** the packaging of this file. Please review the following information to
    ** ensure the GNU General Public License version 2.0 requirements will be
    ** met: http://www.gnu.org/licenses/gpl-2.0.html.
    **
    ** $QT_END_LICENSE$
    **
    ****************************************************************************/

    #include "examplescene.h"
    #include "boxentity.h"

    #include <QTimer>
    #include <qmath.h>

    ExampleScene::ExampleScene(Qt3D::QNode *parent)
        : Qt3D::QEntity(parent)
        , m_timer(new QTimer(this))
        , m_even(true)
    {
        QObject::connect(m_timer, SIGNAL(timeout()), SLOT(updateScene()));
        m_timer->setInterval(1200);
        m_timer->start();
    }

    ExampleScene::~ExampleScene()
    {
        qDeleteAll(m_entities);
    }

    void ExampleScene::updateScene()
    {
        if (m_entities.isEmpty()) {
            buildScene();
        } else {
            int i = 0;
            Q_FOREACH (BoxEntity *entity, m_entities) {
                if (i % 2 == 0)
                    entity->setParent(m_even ? Q_NULLPTR : this);
                else
                    entity->setParent(m_even ? this : Q_NULLPTR);
                ++i;
            }
            m_even = !m_even;
        }
    }

    void ExampleScene::buildScene()
    {
        int count = 20;
        const float radius = 5.0f;

        for (int i = 0; i < count; ++i) {
            BoxEntity *entity = new BoxEntity;
            const float angle = M_PI * 2.0f * float(i) / count;
            entity->setAngle(angle);
            entity->setRadius(radius);
            entity->setDiffuseColor(QColor(qFabs(qCos(angle)) * 255, 204, 75));
            m_entities.append(entity);
        }
    }