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POGetting mouse coordinates method returning different values depending on time called
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  1. POGetting mouse coordinates method returning different values depending on time called
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    copied!<p>I was trying to solve <a href="https://stackoverflow.com/questions/20435152/issue-comparing-doubles">this</a> problem, when I finally found out the reason behind it - calling static methods get_mouse_x() and get_mouse_y() return different results depending on where it was called: if its called from object`s update() method, it always return 0.0, while if its called from draw() method, it returns valid answer.</p> <p>Button class (where problems occurs):</p> <pre><code>public abstract class Button extends Drawable_object { ... @Override public void update() { super.update(); mouseOver_last = mouseOver; mx = Game_logic.get_mouse_x(); my = Game_logic.get_mouse_y(); // for some reasons mx and my are always 0.0 if ((mx &lt;= x + ((double)width / 2))&amp;&amp; (mx &gt;= x - ((double)width / 2))&amp;&amp; (my &gt;= y - ((double)height / 2))&amp;&amp; (my &lt;= y + ((double)height / 2))) { mouseOver = true;} else mouseOver = false; ... } @Override public void draw(Graphics g) { super.draw (g); g.drawString ("x - width / 2 = " + String.valueOf(x - width), 10, 30); g.drawString ("mouse_x = " + String.valueOf(Game_logic.get_mouse_x()), 10, 40); // at this point get_mouse_x() returns true result g.drawString ("x + width / 2 = " + String.valueOf(x + width), 10, 50); g.drawString ("y - width / 2 = " + String.valueOf(y - width), 200, 30); g.drawString ("mouse_y= " + String.valueOf(Game_logic.get_mouse_y()), 200, 40); // at this point get_mouse_y() returns true result g.drawString ("y + width / 2 = " + String.valueOf(y + width), 200, 50); g.drawString ("mouseOver = " + String.valueOf(mouseOver), 10, 80); ... } ... } </code></pre> <p>The mouse coordinates are set in Board class using MouseAdapter:</p> <pre><code>public class Board extends JPanel implements ActionListener { ... private class MAdapter2 extends MouseAdapter { @Override public void mouseMoved(MouseEvent e) { Game_logic.set_mouse_x(e.getX()); Game_logic.set_mouse_y(e.getY()); } } ... } </code></pre> <p>All the things are updated and drawn in same Board class:</p> <pre><code>public void actionPerformed(ActionEvent e) { update(); // calls update() method in every object checkCollisions(); //checks collision repaint(); // calls draw() method in every drawable object } </code></pre> <p>So why does calling Game_logic.get_mouse_x() and Game_logic.get_mouse_y() inside object`s update() method return 0.0 values, and calling them inside objects draw() method always return correct values?</p>
 

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