private void BouncingWindow_MouseDown(Object sender, MouseButtonEventArgs e)
{
if (e.LeftButton == MouseButtonState.Pressed)
{
if (this.bouncingBalls.Count < MainWindow.MaxBalls)
{
BouncingBall ball = new BouncingBall(this.rand);
ball.Left = e.GetPosition(this.BouncingCanvas).X - BouncingBall.Radius;
ball.Top = e.GetPosition(this.BouncingCanvas).Y - BouncingBall.Radius;
Monitor.Enter(this);
this.bouncingBalls.Add(ball);
this.BouncingCanvas.Children.Add(ball.Circle);
Monitor.Exit(this);
}
}
else if (e.RightButton == MouseButtonState.Pressed)
{
int count = this.bouncingBalls.Count;
if (count == 0)
return;
Monitor.Enter(this);
this.bouncingBalls.RemoveAt(count - 1);
this.BouncingCanvas.Children.RemoveAt(count - 1);
Monitor.Exit(this);
}
}
private void BouncingWindow_Loaded(Object sender, RoutedEventArgs e)
{
// create single random generator for all balls
this.rand = new Random();
// add first ball
BouncingBall ball = new BouncingBall(this.rand);
this.bouncingBalls.Add(ball);
this.BouncingCanvas.Children.Add(ball.Circle);
// start bouncing thread
this.bouncingThread = new Thread(this.BouncingThreadProc);
this.stopped = false;
this.bouncingThread.Start();
}
private void CheckCollisions(BouncingBall ball)
{
bool colorswap = false;
for (int i = 0; i < this.bouncingBalls.Count; i++)
{
if (Object.ReferenceEquals(ball, this.bouncingBalls[i]))
continue;
Vector difference = ball.Center - this.bouncingBalls[i].Center;
if (difference.Length <= (BouncingBall.Radius * 2))
{
difference.Normalize();
ball.Direction += difference;
colorswap = true;
}
}
ball.NormalizeDirection();
if (colorswap)
{
if (ball.Circle.Stroke == Brushes.Blue)
ball.Circle.Stroke = Brushes.Red;
else if (ball.Circle.Stroke == Brushes.Red)
ball.Circle.Stroke = Brushes.Green;
else if (ball.Circle.Stroke == Brushes.Green)
ball.Circle.Stroke = Brushes.Yellow;
else if (ball.Circle.Stroke == Brushes.Yellow)
ball.Circle.Stroke = Brushes.White;
else if (ball.Circle.Stroke == Brushes.White)
ball.Circle.Stroke = Brushes.Blue;
}
}
private void MoveBall(BouncingBall ball)
{
// move ball
ball.Left += ball.Direction.X;
ball.Top += ball.Direction.Y;
// check boundaries of window and remaining balls
this.CheckBoundaries(ball);
this.CheckCollisions(ball);
}
private void CheckBoundaries(BouncingBall ball)
{
if (ball.Center.Y < BouncingBall.Radius)
{
// top wall collision, invert direction vertical
if (ball.Direction.Y < 0)
ball.Direction = new Vector(ball.Direction.X, -ball.Direction.Y);
}
else if (ball.Center.Y > (this.BouncingCanvas.ActualHeight - BouncingBall.Radius))
{
// bottom wall collision, invert direction vertical
if (ball.Direction.Y > 0)
ball.Direction = new Vector(ball.Direction.X, -ball.Direction.Y);
}
else if (ball.Center.X < BouncingBall.Radius)
{
// left wall collision, invert direction horizontal
if (ball.Direction.X < 0)
ball.Direction = new Vector(-ball.Direction.X, ball.Direction.Y);
}
else if (ball.Center.X > (this.BouncingCanvas.ActualWidth - BouncingBall.Radius))
{
// left wall collision, invert direction horizontal
if (ball.Direction.X > 0)
ball.Direction = new Vector(-ball.Direction.X, ball.Direction.Y);
}
}