Ellipses do not scale with zoom in WPF sample

Hi and thank you for this repo,

When zooming, ellipses defined in a MapItemsControl do not appear to scale with the zoom level. As you zoom out they get bigger instead of smaller. This is the opposite behavior of a statically defined ellipse, which correctly scales (gets smaller) as you zoom out:

For instance, this works as described above (from your WPF sample app):

<map:MapPath Location="53.5,8.2" Stroke="Blue" StrokeThickness="3" Fill="#1F007F00">
                <map:MapPath.Data>
                    <EllipseGeometry RadiusX="1852" RadiusY="1852"/>
                </map:MapPath.Data>
            </map:MapPath>

But this doesn’t work; Extending your WPF Sample, I display an ellipse for each point location you’ve defined. They display perfectly fine, but as you zoom out they get bigger (whereas static ellipse stays a fixed size)

<Style x:Key="EllipseItemStyle" TargetType="map:MapItem">
            <Setter Property="map:MapPanel.Location" Value="{Binding Location}"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="map:MapItem">
                        <Canvas>
                            <map:MapPath Fill="Red" Opacity="0.7">
                                <map:MapPath.Data>
                                    <EllipseGeometry RadiusX="100" RadiusY="100"/>
                                </map:MapPath.Data>
                            </map:MapPath>
                        </Canvas>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>

And then beside the other mapcontrols:

 <map:MapItemsControl ItemsSource="{Binding Points}"
                                 ItemContainerStyle="{StaticResource EllipseItemStyle}"
                                 SelectionMode="Extended"/>

[ClemensFischer]

There is now a read-only MapTransform property in the MapItem class, which scales and rotates from map to view coordinates.

It may be used like this:

<ControlTemplate TargetType="map:MapItem">
    <Path Fill="Green" Opacity="0.2"
          RenderTransform="{Binding MapTransform, RelativeSource={RelativeSource TemplatedParent}}">
        <Path.Data>
            <EllipseGeometry RadiusX="100" RadiusY="100"/>
        </Path.Data>
    </Path>
</ControlTemplate>

[ClemensFischer]

@YiehraiS Forgot a commit or push last night. Will do later. For the scale bar, see the MapScale class.