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POStrange bug with default constructor (C++)
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copied!<p>First of all, I'd like to apologize in advance if the answer is obvious; I am very new to C++ and my first language is Java. I am also new to Stack Overflow, so if something is wrong with my question or you need anything else, please tell me.</p> <p>So. I have this piece of code here: (I am using SFML for the vector and the CircleShape)</p> <pre><code>Ball::Ball() { // This ugly thing calls the full constructor with a random x and y position // in such a way the the entire ball is inside the screen. Ball::Ball((rand() % (WINDOW_X - (2 * BALL_RADIUS))) + BALL_RADIUS, (rand() % (WINDOW_Y - (2 * BALL_RADIUS))) + BALL_RADIUS); } Ball::Ball(float x, float y) { loc.x = x; loc.y = y; ball.setPosition(loc.x - BALL_RADIUS, loc.y - BALL_RADIUS); ball.setRadius(BALL_RADIUS); ball.setFillColor(sf::Color::Red); ball.setOutlineColor(sf::Color::Black); ball.setOutlineThickness(1); } </code></pre> <p>And here is the header (#included into the above file):</p> <pre><code>class Ball { private: sf::CircleShape ball; sf::Vector2f loc; sf::Vector2f vel; sf::Vector2f acc; void update(); void bounce(); void draw(); public: Ball(); Ball(float x, float y); void run(); }; </code></pre> <p>When I create the ball with</p> <pre><code>Ball ball; </code></pre> <p>(and yes, all of the SFML rendering stuff works), it never shows. A bit of investigation shows that its loc.x and loc.y variables are not set, and probably, neither are the radius, fillcolor, etc of the ball object. If I print the values of these with std::cout <em>inside</em> the constructor, loc.x and loc.y and all the others <em>are</em> set, so I assume that they get unset somewhere after the constructor. What is strange is that if I create the ball with </p> <pre><code>Ball ball((rand() % (WINDOW_X - (2 * BALL_RADIUS))) + BALL_RADIUS, (rand() % (WINDOW_Y - (2 * BALL_RADIUS))) + BALL_RADIUS); </code></pre> <p>or even</p> <pre><code>Ball ball(400, 300); </code></pre> <p>everything works perfectly, and the ball shows up on-screen. I am really stumped guys. If anyone could help me, that would be great.</p> <p>BTW, I am running OS X 10.8 with Xcode 4.5.2, and using SFML RC2.0, if that makes any difference.</p> <p>Thanks,</p> <p>Matt</p>

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