MouseEvent too slow or am I missing something?

[Ivan Slavka]

Hi guys,

a month ago I decided to try to create a simple game. Well actually it's mostly playing with Java2D then creating a game.
Anyway here is my problem. I decided to learn how to move a shape (Sphere) based on the mouse position.
Ex. If I drag the mouse, the sphere follows the mouse, if I just press the button the sphere starts to move toward the mouse position.

My problem is I can't figure out how to stop the sphere when it's bounds contain the mouse position, basically when the sphere gets to the mouse it should stop.
Well to be more precise, I know how to do the logic to calculate if the mouse point is inside the sphere bounds, but the sphere doesn't stop. It just passes through.
And on some occasions when I start to drag the mouse very fast it stops.

At first I thought that it was concurrency problem (Main thread paints the sphere, MouseEvent thread assigns the mouse position), and I tested with locks, but the result was the same.
Is it possible that Java is just too slow for even this kind of simple animation, or am I missing something?

Here is my code:

Main class

...
@Override
	public void paint(Graphics g){

		g.setColor(Color.BLACK);
		g.fillRect(0,0,this.boardWidth, this.boardHeight);
		g.setColor(Color.WHITE);
		g.drawString("MoveAngle: " + this.ball.getMoveAngle() + " Mouse position(" + this.ball.getMouseX() + ", " + this.ball.getMouseY() + ")" , 20, 20);
		this.ball.drawBall(g);
	}

	@Override
	public void run() {

		while(true){
			try {
				Thread.sleep(1000 / FRAMES_PER_SECOND);
				this.repaint();
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
		}
	}
...

Ball class

...

// method where I perform the check for collision with the mouse, as you can see, neither way is successful.
private void moveSphere(){
		this.checkForCollisionWithBounds();
		//		if(this.getBounds().contains(this.mousePoint)){
		//			this.speed = 0;
		//		}
		if((this.mouseX >= this.x && this.mouseX <= this.x + this.radius) &&
				(this.mouseY >= this.y && this.mouseY <= this.y + this.radius)) {
			this.speed = 0;
		}
		this.x += this.speedX;
		this.y += this.speedY;
	}

	public void drawBall(Graphics g){
		this.moveSphere();
		
		g.setColor(Color.RED);
		g.fillOval((int)this.x,
				(int)this.y,
				(2 * this.radius),
				(2 * this.radius));
	}
...
@Override
	public void mousePressed(MouseEvent e) {

		switch(e.getButton()){
		case MouseEvent.BUTTON1:
			this.mouseX = e.getPoint().getX();
			this.mouseY = e.getPoint().getY();
			break;
		}
		this.speed = 5;

                // Math to calculate what is the angle of ball movement
		double centerX = this.x + this.radius;
		double centerY = this.y + this.radius;

		double adjectant = this.mouseX - centerX;
		double opposite = centerY - this.mouseY;

		double tangent = opposite / adjectant;
		this.moveAngle = Math.toDegrees(Math.atan(tangent));
		if(adjectant < 0){
			this.moveAngle += 180;
		}
		if(this.moveAngle < 0){
			this.moveAngle += 360;
		} else if (this.moveAngle > 360){
			this.moveAngle -= 360;
		}

		this.mousePoint.setLocation((int)this.mouseX, (int)this.mouseY);

		this.calculateVelocity();
	}
...

[Darryl Burke]

Please UseOneThreadPerQuestion. I'm locking this one. Continue in http://www.coderanch.com/t/566611/GUI/java/MouseEvent-too-slow-or-missing