public bool IsColiding(Ball ball)
{
double d = (Center.X - ball.Center.X) * (Center.X - ball.Center.X) + (Center.Y - ball.Center.Y) * (Center.Y - ball.Center.Y);
return d <= (2 * RADIUS) * (2 * RADIUS);
}
public void AddBall(Ball ball)
{
Balls.Add(ball);
}
private void Form1_MouseClick(object sender, MouseEventArgs e)
{
Ball ball = new Ball(e.Location, currentColor);
ballsDoc.AddBall(ball);
Invalidate(true);
}