Revision control

++ #include <QGuiApplication>
++ #include <QQmlApplicationEngine>
++ #include <QtQuick3D/qquick3d.h>
++
++ int main(int argc, char *argv[])
++ {
++ QGuiApplication app(argc, argv);
++
++ QSurfaceFormat::setDefaultFormat(QQuick3D::idealSurfaceFormat());
++
++ QQmlApplicationEngine engine;
++ engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
++ if (engine.rootObjects().isEmpty())
++ return -1;
++
++ return app.exec();
++ }