Qt 5.6 | Qt 3D | Qt 3D: Simple C++ Example | main.cpp Example File

Qt 5.6.3 Reference Documentation

# main.cpp Example File

simple-cpp/main.cpp

      /****************************************************************************
      **
      ** Copyright (C) 2014 Klaralvdalens Datakonsult AB (KDAB).
      ** Contact: http://www.qt-project.org/legal
      **
      ** This file is part of the Qt3D module of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:LGPL3$
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      **
      ** 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.
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      #include <QGuiApplication>

      #include <Qt3DCore/QEntity>
      #include <Qt3DCore/QCamera>
      #include <Qt3DCore/QCameraLens>
      #include <Qt3DCore/QTransform>
      #include <Qt3DCore/QAspectEngine>

      #include <Qt3DInput/QInputAspect>

      #include <Qt3DRender/QRenderAspect>
      #include <Qt3DRender/QFrameGraph>
      #include <Qt3DRender/QForwardRenderer>
      #include <Qt3DRender/QPhongMaterial>
      #include <Qt3DRender/QCylinderMesh>
      #include <Qt3DRender/QSphereMesh>
      #include <Qt3DRender/QTorusMesh>
      #include <Qt3DRender/QWindow>

      #include <QPropertyAnimation>

      class OrbitTransformController : public QObject
      {
          Q_OBJECT
          Q_PROPERTY(Qt3DCore::QTransform* target READ target WRITE setTarget NOTIFY targetChanged)
          Q_PROPERTY(float radius READ radius WRITE setRadius NOTIFY radiusChanged)
          Q_PROPERTY(float angle READ angle WRITE setAngle NOTIFY angleChanged)

      public:
          OrbitTransformController(QObject *parent = 0)
              : QObject(parent)
              , m_target(Q_NULLPTR)
              , m_matrix()
              , m_radius(1.0f)
              , m_angle(0.0f)
          {
          }

          void setTarget(Qt3DCore::QTransform *target)
          {
              if (m_target != target) {
                  m_target = target;
                  emit targetChanged();
              }
          }

          Qt3DCore::QTransform *target() const { return m_target; }

          void setRadius(float radius)
          {
              if (!qFuzzyCompare(radius, m_radius)) {
                  m_radius = radius;
                  updateMatrix();
                  emit radiusChanged();
              }
          }

          float radius() const { return m_radius; }

          void setAngle(float angle)
          {
              if (!qFuzzyCompare(angle, m_angle)) {
                  m_angle = angle;
                  updateMatrix();
                  emit angleChanged();
              }
          }

          float angle() const { return m_angle; }

      signals:
          void targetChanged();
          void radiusChanged();
          void angleChanged();

      protected:
          void updateMatrix()
          {
              m_matrix.setToIdentity();
              m_matrix.rotate(m_angle, QVector3D(0.0f, 1.0f, 0.0f));
              m_matrix.translate(m_radius, 0.0f, 0.0f);
              m_target->setMatrix(m_matrix);
          }

      private:
          Qt3DCore::QTransform *m_target;
          QMatrix4x4 m_matrix;
          float m_radius;
          float m_angle;
      };

      int main(int argc, char* argv[])
      {
          QGuiApplication app(argc, argv);
          Qt3DRender::QWindow view;
          Qt3DInput::QInputAspect *input = new Qt3DInput::QInputAspect;
          view.registerAspect(input);

          // Root entity
          Qt3DCore::QEntity *rootEntity = new Qt3DCore::QEntity();

          // Camera
          Qt3DCore::QCamera *cameraEntity = view.defaultCamera();

          cameraEntity->lens()->setPerspectiveProjection(45.0f, 16.0f/9.0f, 0.1f, 1000.0f);
          cameraEntity->setPosition(QVector3D(0, 0, -40.0f));
          cameraEntity->setUpVector(QVector3D(0, 1, 0));
          cameraEntity->setViewCenter(QVector3D(0, 0, 0));
          input->setCamera(cameraEntity);

          // Material
          Qt3DRender::QMaterial *material = new Qt3DRender::QPhongMaterial(rootEntity);

          // Torus
          Qt3DCore::QEntity *torusEntity = new Qt3DCore::QEntity(rootEntity);
          Qt3DRender::QTorusMesh *torusMesh = new Qt3DRender::QTorusMesh;
          torusMesh->setRadius(5);
          torusMesh->setMinorRadius(1);
          torusMesh->setRings(100);
          torusMesh->setSlices(20);

          Qt3DCore::QTransform *torusTransform = new Qt3DCore::QTransform;
          torusTransform->setScale3D(QVector3D(1.5, 1, 0.5));
          torusTransform->setRotation(QQuaternion::fromAxisAndAngle(QVector3D(1, 0, 0), 45.0f));

          torusEntity->addComponent(torusMesh);
          torusEntity->addComponent(torusTransform);
          torusEntity->addComponent(material);

          // Sphere
          Qt3DCore::QEntity *sphereEntity = new Qt3DCore::QEntity(rootEntity);
          Qt3DRender::QSphereMesh *sphereMesh = new Qt3DRender::QSphereMesh;
          sphereMesh->setRadius(3);

          Qt3DCore::QTransform *sphereTransform = new Qt3DCore::QTransform;
          OrbitTransformController *controller = new OrbitTransformController(sphereTransform);
          controller->setTarget(sphereTransform);
          controller->setRadius(20.0f);

          QPropertyAnimation *sphereRotateTransformAnimation = new QPropertyAnimation(sphereTransform);
          sphereRotateTransformAnimation->setTargetObject(controller);
          sphereRotateTransformAnimation->setPropertyName("angle");
          sphereRotateTransformAnimation->setStartValue(QVariant::fromValue(0));
          sphereRotateTransformAnimation->setEndValue(QVariant::fromValue(360));
          sphereRotateTransformAnimation->setDuration(10000);
          sphereRotateTransformAnimation->setLoopCount(-1);
          sphereRotateTransformAnimation->start();

          sphereEntity->addComponent(sphereMesh);
          sphereEntity->addComponent(sphereTransform);
          sphereEntity->addComponent(material);

          view.setRootEntity(rootEntity);
          view.show();

          return app.exec();
      }

      #include "main.moc"