Sub-Attaq

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Q_INIT_RESOURCE(subattaq);

    MainWindow w;
    w.show();

    return app.exec();
}

    QMenu *file = menuBar()->addMenu(tr("&File"));

    QAction *newAction = file->addAction(tr("New Game"));
    newAction->setShortcut(QKeySequence(Qt::CTRL | Qt::Key_N));
    QAction *quitAction = file->addAction(tr("Quit"));
    quitAction->setShortcut(QKeySequence(Qt::CTRL | Qt::Key_Q));

    if (QApplication::arguments().contains("-fullscreen")) {
        scene = new GraphicsScene(0, 0, 750, 400, GraphicsScene::Small, this);
        setWindowState(Qt::WindowFullScreen);
    } else {
        scene = new GraphicsScene(0, 0, 880, 630, GraphicsScene::Big, this);
        layout()->setSizeConstraint(QLayout::SetFixedSize);
    }

    view = new QGraphicsView(scene, this);
    view->setAlignment(Qt::AlignLeft | Qt::AlignTop);
    scene->setupScene(newAction, quitAction);
    setCentralWidget(view);

    machine = new QStateMachine;

    //This state is active when the player is playing
    LevelState *levelState = new LevelState(scene, this, machine);

    //This state is active when the player is actually playing but the game is not paused
    QState *playingState = new QState(levelState);
    levelState->setInitialState(playingState);

    //This state is active when the game is paused
    PauseState *pauseState = new PauseState(scene, levelState);

    //We have one view, it receives the key press events
    QKeyEventTransition *pressPplay = new QKeyEventTransition(scene->views().at(0), QEvent::KeyPress, Qt::Key_P);
    pressPplay->setTargetState(pauseState);
    QKeyEventTransition *pressPpause = new QKeyEventTransition(scene->views().at(0), QEvent::KeyPress, Qt::Key_P);
    pressPpause->setTargetState(playingState);

    //Pause "P" is triggered, when the player pauses the game
    playingState->addTransition(pressPplay);

    //To get back to playing when the game has been paused
    pauseState->addTransition(pressPpause);

    //This state is active when player has lost
    LostState *lostState = new LostState(scene, this, machine);

    //This state is active when player has won
    WinState *winState = new WinState(scene, this, machine);

    //If boat has been destroyed then the game is finished
    levelState->addTransition(scene->boat, &Boat::boatExecutionFinished,lostState);

    //This transition checks if we have won or not
    WinTransition *winTransition = new WinTransition(scene, this, winState);

    //If boat has been destroyed then the game is finished
    levelState->addTransition(winTransition);

    //This state is for an animation when the score changes
    UpdateScoreState *scoreState = new UpdateScoreState(levelState);

    //This transition updates the score when a submarine is destroyed
    UpdateScoreTransition *scoreTransition = new UpdateScoreTransition(scene, this, levelState);
    scoreTransition->setTargetState(scoreState);

    //If the boat has been destroyed then the game is finished
    playingState->addTransition(scoreTransition);

    //We go back to play state
    scoreState->addTransition(playingState);

    //We start playing!!!
    machine->setInitialState(levelState);

    //Final state
    QFinalState *finalState = new QFinalState(machine);

    //This transition is triggered when the player presses space after completing a level
    CustomSpaceTransition *spaceTransition = new CustomSpaceTransition(scene->views().at(0), this, QEvent::KeyPress, Qt::Key_Space);
    spaceTransition->setTargetState(levelState);
    winState->addTransition(spaceTransition);

    //We lost so we should reach the final state
    lostState->addTransition(lostState, &QState::finished, finalState);

    scene->textInformationItem->hide();
    machine->start();

void LevelState::initializeLevel()
{
    //we re-init the boat
    scene->boat->setPos(scene->width()/2, scene->sealLevel() - scene->boat->size().height());
    scene->boat->setCurrentSpeed(0);
    scene->boat->setCurrentDirection(Boat::None);
    scene->boat->setBombsLaunched(0);
    scene->boat->show();
    scene->setFocusItem(scene->boat, Qt::OtherFocusReason);
    scene->boat->run();

    scene->progressItem->setScore(game->score);
    scene->progressItem->setLevel(game->currentLevel + 1);

    const GraphicsScene::LevelDescription currentLevelDescription = scene->levelsData.value(game->currentLevel);
    for (const QPair<int,int> &subContent : currentLevelDescription.submarines) {

        GraphicsScene::SubmarineDescription submarineDesc = scene->submarinesData.at(subContent.first);

        for (int j = 0; j < subContent.second; ++j ) {
            SubMarine *sub = new SubMarine(submarineDesc.type, submarineDesc.name, submarineDesc.points);
            scene->addItem(sub);
            int random = QRandomGenerator::global()->bounded(15) + 1;
            qreal x = random == 13 || random == 5 ? 0 : scene->width() - sub->size().width();
            qreal y = scene->height() -(QRandomGenerator::global()->bounded(150) + 1) - sub->size().height();
            sub->setPos(x,y);
            sub->setCurrentDirection(x == 0 ? SubMarine::Right : SubMarine::Left);
            sub->setCurrentSpeed(QRandomGenerator::global()->bounded(3) + 1);
        }
    }
}