private void button1_Click(object sender, RoutedEventArgs e) { for (int cntr = 1; cntr <= 1; cntr++) { Color lineColor = UtilityWPF.GetRandomColor(64, 192); ScreenSpaceLines3D lineModel = new ScreenSpaceLines3D(false); lineModel.Thickness = 1d; lineModel.Color = lineColor; Point3D fromPoint = Math3D.GetRandomVector(15d).ToPoint(); Point3D toPoint = Math3D.GetRandomVector(15d).ToPoint(); //lineModel.AddLine(fromPoint, toPoint); lineModel.Points.Add(fromPoint); lineModel.Points.Add(toPoint); _viewport.Children.Add(lineModel); lineModel.CalculateGeometry(); _lastLine = lineModel; } }