如何从最近的点找到路径上的点

user128300有一个很好的解决方案获取路径或折线上最接近断开点的点但是我似乎不能正确地使用边距来定位点。

Xaml代码

<Style x:Key="Test_Path_Actual" TargetType="Path">
    <Setter Property="Stroke" Value="Blue"/>
    <Setter Property="StrokeThickness" Value="1"/>
    <Setter Property="StrokeLineJoin" Value="Round"/>
    <Setter Property="Stretch" Value="Fill"/>
    <Setter Property="Data" Value="M 0,20 L 30 0 L 60,20 L 30,40 Z"/>
</Style>
<Style TargetType="{x:Type c:ConnectorStrip}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type c:ConnectorStrip}">
                <Grid x:Name="PART_Grid" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
                    <Path x:Name="PART_PathActual" Style="{StaticResource Test_Path_Actual}"/>
                    <Path x:Name="PART_PathHitArea" Style="{StaticResource Test_Path_Hit_Area}"/>
                    <s:ConnectorSeeker x:Name="PART_ConnectorSeeker" Visibility="collapsed"/>
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

c#代码

    void hitPath_MouseEnter(object sender, MouseEventArgs e)
    {
        ScaleX = this.DesiredSize.Width / origWidth;
        ScaleY = this.DesiredSize.Height / origHeight;
        ConnectorSeeker connSeekerL = GetConnectorSeeker();
        Point pt = GetClosestPointOnPath(e.GetPosition(this), actualPath.Data);
        if (connSeekerL != null)
        {
            double marginLeft = pt.X - (connSeekerL.Width / 2);
            double marginTop = pt.Y - (connSeekerL.Height / 2);
            double marginRight = this.DesiredSize.Width - pt.X - (connSeekerL.Width / 2);
            double marginBottom = this.DesiredSize.Height - pt.Y - (connSeekerL.Height / 2);
            connSeekerL.Margin = new Thickness(marginLeft, marginTop, marginRight, marginBottom);
            connSeekerL.Visibility = System.Windows.Visibility.Visible;
        }
        else
        {
            throw new Exception("Cannot find connector seeker");
        }
    }

当为当前光标位置使用e.t getposition (this)时，边距定位逻辑工作良好，但我希望该点位于最近的路径上