void CompositionTarget_Rendering(object sender, EventArgs e)
{
if (ellipses.Count == 0)
{
int halfCanvasWidth = (int)canvas.ActualWidth / 2;
Random rnd = new Random();
int count = rnd.Next(minEllipses, maxEllipses);
for (int i = 0; i < count; i++)
{
Ellipse ellipse = new Ellipse();
ellipse.Fill = Brushes.LimeGreen;
ellipse.Width = ellipseRadius;
ellipse.Height = ellipseRadius;
Canvas.SetLeft(ellipse, halfCanvasWidth + rnd.Next(-halfCanvasWidth, halfCanvasWidth));
Canvas.SetTop(ellipse, 0);
canvas.Children.Add(ellipse);
EllipseInfo info = new EllipseInfo(ellipse, speedRatio * rnd.Next(minStartingSpeed, maxStartingSpeed));
ellipses.Add(info);
}
}
else
{
for (int i = 0; i < ellipses.Count - 1; i++)
{
EllipseInfo info = ellipses[i];
double top = Canvas.GetTop(info.Ellipse);
Canvas.SetTop(info.Ellipse, top + 1 * info.VelocityY);
if (Top >= (canvas.ActualHeight - ellipseRadius * 2))
{
ellipses.Remove(info);
}
else
{
info.VelocityY += accelerationY;
}
}
if (ellipses.Count == 0)
{
CompositionTarget.Rendering -= CompositionTarget_Rendering;
rendering = false;
}
}
}
private void DrawEllipse(EllipseInfo e)
{
var ell = new System.Windows.Shapes.Ellipse();
ell.StrokeThickness = 2;
ell.Stroke = Brushes.Black;
Shapes.Ellipse myEll = new Shapes.Ellipse(new Vec2f(e.f1[0], e.f1[1]),
new Vec2f(e.f2[0], e.f2[1]), e.bigO);
ell.Height = myEll.a * 2 * 100;
ell.Width = myEll.b * 2 * 100;
panel.Children.Add(ell);
}