WPF Path disappears at some size

I have encountered this problem while scaling graph, which is drawn over GIS control Greatmap. But a simple experiment persuades me that problems is somewhere deeper in WPF.

Consider simple WPF application:

This is MainWindow.xaml

<Grid>
    <StackPanel>
        <Slider ValueChanged="Size_Changed" Minimum="0" Maximum="300000"/>
        <TextBox x:Name="Value"></TextBox>
    </StackPanel>
    <Canvas>
        <Path x:Name="MyPath" Stroke="Black" StrokeThickness="2" />
    </Canvas>
</Grid>

And this is its code behind

private void Size_Changed(object sender,
        RoutedPropertyChangedEventArgs<double> e)
    {
        if (MyPath == null) return;
    var g = new StreamGeometry();
    using (var s = g.Open())
    {
        var pointA = new Point(0, 200);

        s.BeginFigure(pointA, false, false);

        var pointB = new Point(e.NewValue, 200);

        s.PolyLineTo(new[] {pointB}, true, true);

        Value.Text = $"zoom = {e.NewValue:0.0} ;  pointA = {pointA.X:#,0} ; pointB = {pointB.X:#,0}";
    }

    g.Freeze();

    MyPath.Data = g;
}

While I drag slider from 0 to 249999 it’s all right. I can see line on my view. But at the very moment slider’s value becomes 250000 – line disappears.

Is there any limitations in WPF ?

#c-sharp #wpf