Java shoot towards mouse

Question

I have a top down 2d game where you walk around shooting bad guys. I want to be able to shoot towards the mouse, no mater what direction it is but I have absolutely no idea how to do this.

Here is my bullet class:

public class bullet {

public double x, y,dy,dx,mx,my;
public int dir;

public Rectangle r = new Rectangle((int) x, (int) y, 5, 5);

public bullet(double x, double y) {
    this.x = x+10;
    this.y = y+10;
    this.mx = Comp.mx;
    this.my = Comp.my;
    r = new Rectangle((int) x, (int) y, 5, 5);
    if (x < mx+play.camx) {
        dx = 1;
    }
    if (x > mx+play.camx) {
        dx = -1;
    }
    if (y < my+play.camy) {
        dy = 1;
    }
    if (y > my+play.camy) {
        dy = -1;
    }
}

public void tick() {
    x+=dx;
    y+=dy;

    r = new Rectangle((int) x - play.camx, (int) y - play.camy, 5, 5);
}

public void render(Graphics g) {
    g.setColor(Color.black);
    g.fillRect((int) x - play.camx, (int) y - play.camy, 5, 5);
}
}

So you have two points (start//end), you need to calculate the angel between them — MadProgrammer, Dec 18 '14 at 19:49
http://wikicode.wikidot.com/get-angle-of-line-between-two-points — Mike G, Dec 18 '14 at 19:55

score 2 · Answer 1 · edited May 23 '17 at 12:14

Basicially, you need calculate the angel between the start point and end point, something like...

angle = -Math.toDegrees(Math.atan2(startX - endX, startY - endY)) + 180;

As an example:

To track the mouse, use a MouseListener and MouseMotionListerner

Take a look at:

score 0 · Answer 2 · answered Dec 18 '14 at 19:54

0

Try using MouseInfo.getPointerInfo().getPosition() ( http://download.oracle.com/javase/1.5.0/docs/api/java/awt/PointerInfo.html#getLocation%28%29) It will return a point object. Use a timer and on every timer event you'll move your bullet a specific length (which you would want it to move) towards the mouse position provided by aforementioned method. You could do it like reducing difference of x- and y- Variables of mouse position and bullet position.

answered Dec 18 '14 at 19:54

Niklas

375
1
3
17

I am trying to do this without using added libraries – user2279603 Dec 18 '14 at 19:57
Have you considered attaching a mouselistener to the panel or something where you're drawing in? – Niklas Dec 18 '14 at 20:00
yes I have no problem getting the cords of mouse x and mouse y I just cant do the angle and direction of the bullet – user2279603 Dec 18 '14 at 20:03
Or use a MouseMotionListener and get the call backs for free – MadProgrammer Dec 18 '14 at 20:05
Use the Pythagorean theorem – Niklas Dec 18 '14 at 20:05

Java shoot towards mouse

2 Answers2

Linked