cvMap.Children.Clear();
                foreach (Teilstrecke teilstrecke in teilstrecken)
                {
                    Line line = new Line();
                    if (teilstrecke.vonOrt.StartsWith("A"))
                        line.Stroke = Brushes.Red;
                    else if (teilstrecke.vonOrt.StartsWith("B"))
                        line.Stroke = Brushes.Blue;
                    else
                        line.Stroke = Brushes.Green;
                    sizeFactorX = cvMap.ActualWidth / 60000.0;
                    sizeFactorY = cvMap.ActualHeight / 30000.0;
                    line.X1 = teilstrecke.vonPoint.X * sizeFactorX;
                    line.X2 = teilstrecke.bisPoint.X * sizeFactorX;
                    line.Y1 = teilstrecke.vonPoint.Y * sizeFactorY;
                    line.Y2 = teilstrecke.bisPoint.Y * sizeFactorY;
                    line.StrokeThickness = 2;
                    cvMap.Children.Add(line);
                }