private void DrawLine(double x1, double y1, double x2, double y2, ChartPlotInfo info, Brush brush, bool isDashed = false)
        {
            var line = new Line();

            line.X1              = GeometricHelper.XCoordToChart(x1, info);
            line.X2              = GeometricHelper.XCoordToChart(x2, info);
            line.Y1              = GeometricHelper.YCoordToChart(y1, info);
            line.Y2              = GeometricHelper.YCoordToChart(y2, info);
            line.Stroke          = brush;
            line.StrokeThickness = 2;
            if (isDashed)
            {
                line.StrokeThickness  = 1;
                line.StrokeDashOffset = 5;
            }

            RenderElement(line);
        }
        private void DrawCircle(DateTime dateTime, double p, ChartPlotInfo info, Brush brush)
        {
            var circle = new Ellipse();

            circle.ToolTip = string.Format("Дата: {0:yyyy MMM dd}, значення: {1}", dateTime, p);

            circle.Stroke = brush;
            circle.Fill   = Brushes.White;

            circle.Width           = 10;
            circle.Height          = 10;
            circle.StrokeThickness = 2;
            var x = GeometricHelper.DateToChart(dateTime, info) - circle.Width / 2;
            var y = GeometricHelper.YCoordToChart(p, info) - circle.Height / 2;

            Canvas.SetTop(circle, y);
            Canvas.SetLeft(circle, x);

            RenderElement(circle);
        }
        private void DrawLine(DateTime x1, double y1, DateTime x2, double y2, ChartPlotInfo info, Brush brush, bool isDashed = false)
        {
            var line = new Line();

            line.X1              = GeometricHelper.DateToChart(x1, info);
            line.X2              = GeometricHelper.DateToChart(x2, info);
            line.Y1              = GeometricHelper.YCoordToChart(y1, info);
            line.Y2              = GeometricHelper.YCoordToChart(y2, info);
            line.Stroke          = brush;
            line.StrokeThickness = 2;
            if (isDashed)
            {
                DoubleCollection dashes = new DoubleCollection(2);
                dashes.Add(5);
                dashes.Add(5);
                line.StrokeThickness = 1;
                line.StrokeDashArray = dashes;
            }

            RenderElement(line);
        }