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POShoot to the mouse direction
 

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    <h2>The problem:</h2> <p>I've got this "Shot" class. In the code, the target variables are the mouseX and mouseY. So when i click the mouse button, my player class will create a new shot object. But the shooting is inaccurate. How can i calculate the correct dx and dy?</p> <p>If i add the dx and dy to the "bullet's" x and y, the bullet will move to the mouse's direction.This is what i want. The mouse position is stored in targetX and targetY, when the object is created. This is the point what the oval wants to reach.</p> <p><strong>Links:</strong></p> <blockquote> <p><a href="https://www.dropbox.com/s/dhvf5vbqj25sgyw/game.jar" rel="nofollow"><strong><em>The game (finished)</em></strong></a><br/></p> </blockquote> <p><strong>The code (from Shot.java):</strong> </p> <pre><code>public class Shot extends Entity { private float targetX, targetY; public Shot(World world, float x, float y, int width, int height, Color color, float targetX, float targetY) { super(world, x, y, width, height, color); this.targetX = targetX; this.targetY = targetY; } @Override public void render(GameContainer gc, Graphics g, Camera camera) { g.setColor(color); g.fillOval(x - camera.getX(), y - camera.getY(), width, height); } @Override public void update(GameContainer gc, int delta) { float dx = targetX - x; float dy = targetY - y; x += dx * delta * .001f; y += dy * delta * .001f; } } </code></pre> <p><strong>I tried this, but still not work:</strong></p> <pre><code>@Override public void update(GameContainer gc, int delta) { float length = (float) Math.sqrt((targetX - x) * (targetX - x) + (targetY - y) * (targetY - y)); double dx = (targetX - x) / length * delta; double dy = (targetY - y) / length * delta; x += dx; y += dy; } </code></pre> <p><strong>I did it! Here is my solution:</strong> <br/> The problem was that, the target was the window's mouse position, and not the world's mouse position. <br/></p> <p>This is how i calculated the world's mouse positions: <br/></p> <pre><code>float mouseWorldX = x + (mouseX - screen_width / 2); // x = player's x position float mouseWorldY = y + (mouseY - screen_height / 2); // y = player's y position </code></pre>
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    1. COPlease add more information about how you want the dx and dy to work. (Edit the quesiton). Thanks
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    2. COI try to add as much information as i can
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