Show axis scale

Hello.

I'm just stuck.

I've starte research Helix-tookit. I very like, but I have some troubles.

 I want to display axis scale(perfectly it's display real numbers corresponding to grid node)

Markup looks like

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<Window x:Class="UpDirectionDemo.MainWindow" 
 xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
 xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:h="clr-namespace:HelixToolkit.Wpf;assembly=HelixToolkit.Wpf" Title="UpDirectionDemo" Height="480" Width="640" xmlns:local="clr-namespace:UpDirectionDemo" > 
 <DockPanel> 
 <TextBlock DockPanel.Dock="Top" HorizontalAlignment="Center" Text="HelixViewport3D.ModelUpDirection = 0,1,0" Padding="8" Foreground="Black"/> 
 <h:HelixViewport3D x:Name="view1" CameraRotationMode="Turntable" ModelUpDirection="0,1,0" ShowCoordinateSystem="True" > 
 <h:HelixViewport3D.Camera> 
 <PerspectiveCamera Position="5, 30, 40" LookDirection="-5, -30, -40" FieldOfView="45" UpDirection="0,1,0"/> 
 </h:HelixViewport3D.Camera> 
 <h:DefaultLights/> 
 <h:CoordinateSystemVisual3D ArrowLengths="10" /> 
 <h:BillboardTextVisual3D Position="12 0 0" FontSize="24" Text="X" /> 
 <h:BillboardTextVisual3D Position="0 12 0" FontSize="24" Text="Y" /> 
 <h:BillboardTextVisual3D Position="0 0 12" FontSize="24" Text="Z" /> 
 <h:GridLinesVisual3D Normal="0,1,0" LengthDirection="1,0,0"/> 
 </h:HelixViewport3D> 
 </DockPanel> 
</Window> 

--------------------------

I cant find this params. I've just only found ThetaDiv in ArrowVisual3D class. 

Is any way to display to display what I want? Thearetically I can create my own class MyArrowVisual3D(extends from ArrowVisual3D ) and create method for display it, but it to complex, I guess.

Thx!