SFML movement

#include <SFML/Graphics.hpp>
#include <vector>
#include <cstdlib>
#include <ctime>

class Game {
  public:
    Game();
    void run();

  private:
    void processEvents();
    void handleUserInput(sf::Keyboard::Key key, bool isPressed);
    void update(sf::Time deltaTime);
    void render();

  private:
      static const sf::Time TimePerFrame;
      static const float PlayerSpeed;
      sf::RenderWindow mWindow;
      sf::View mView;

      std::vector<sf::RectangleShape> mRectangles;
      sf::RectangleShape mPlayer;
      bool mIsMovingUp;
      bool mIsMovingDown;
      bool mIsMovingLeft;
      bool mIsMovingRight;
};
const sf::Time Game::TimePerFrame = sf::seconds(1.f/60.f);
const float Game::PlayerSpeed = 150.f;

Game::Game()
: mWindow(sf::VideoMode(800, 600), "Test")
, mIsMovingUp(false)
, mIsMovingDown(false)
, mIsMovingLeft(false)
, mIsMovingRight(false)
{
    mView = mWindow.getView();

    mPlayer.setPosition(100.f, 100.f);
    mPlayer.setSize(sf::Vector2f(10.f, 10.f));
    mPlayer.setFillColor(sf::Color::Green);

    //create some shapes just for viewing
    float pos_x;
    float pos_y = 20.f;
    for (int i = 0; i < 20; i++)
    {
        pos_x = rand()%800;
        pos_y = rand()%600;

        sf::RectangleShape rect;
        rect.setPosition(pos_x, pos_y);
        rect.setSize(sf::Vector2f(20.f, 20.f));
        mRectangles.push_back(rect);
    }
}


void Game::run()
{
    mWindow.setVerticalSyncEnabled(true); //can be changed later to take from config file

    sf::Clock clock;
    sf::Time timeSinceLastUpdate = sf::Time::Zero;
    while (mWindow.isOpen())
    {
        sf::Time elapsedTime = clock.restart();
        timeSinceLastUpdate += elapsedTime;
        while (timeSinceLastUpdate > TimePerFrame)
        {
            timeSinceLastUpdate -= TimePerFrame;
            processEvents();
            update(TimePerFrame);
        }
        render();
    }
}

void Game::handleUserInput(sf::Keyboard::Key key, bool isPressed)
{
    if (key == sf::Keyboard::W)
        mIsMovingUp = isPressed;
    else if (key == sf::Keyboard::S)
        mIsMovingDown = isPressed;
    else if (key == sf::Keyboard::A)
        mIsMovingLeft = isPressed;
    else if (key == sf::Keyboard::D)
        mIsMovingRight = isPressed;
}

void Game::processEvents()
{
    sf::Event event;
    while (mWindow.pollEvent(event))
    {
        switch(event.type)
        {
            case sf::Event::KeyPressed:
                handleUserInput(event.key.code, true);
                break;
            case sf::Event::KeyReleased:
                handleUserInput(event.key.code, false);
                break;
            case sf::Event::Closed:
                mWindow.close();
                break;
        }
    }
}

void Game::update(sf::Time deltaTime)
{
    sf::Vector2f movement(0.f, 0.f);
    if (mIsMovingUp)
        movement.y -= PlayerSpeed;
    if (mIsMovingDown)
        movement.y += PlayerSpeed;
    if (mIsMovingLeft)
        movement.x -= PlayerSpeed;
    if (mIsMovingRight)
        movement.x += PlayerSpeed;
    mPlayer.move(movement*deltaTime.asSeconds());
}


void Game::render()
{
    mWindow.clear();

    mView.setCenter(mPlayer.getPosition());
    mWindow.setView(mView);

    mWindow.draw(mPlayer);
    for (int i = 0; i < mRectangles.size(); i++)
        mWindow.draw(mRectangles[i]);
    mWindow.display();
}

int main()
{
    srand(time(NULL));
    Game game;
    game.run();
    return 0;
}