''' <summary>
''' Sets the color for first and second points of WPF arc annotation.
''' </summary>
''' <param name="arcAnnotationView">The WPF arc annotation view.</param>
''' <param name="firstArcPointColor">The color of the first point of arc annotation.</param>
''' <param name="secondArcPointColor">The color of the second point of arc annotation.</param>
Public Sub SetInteractionPointsColor(arcAnnotationView As Vintasoft.Imaging.Annotation.Wpf.UI.WpfArcAnnotationView, firstArcPointColor As System.Windows.Media.Color, secondArcPointColor As System.Windows.Media.Color)
    If arcAnnotationView Is Nothing Then
        Return
    End If

    SetInteractionPointsColor(arcAnnotationView.InteractionController, firstArcPointColor, secondArcPointColor)
End Sub

''' <summary>
''' Finds the <see cref="Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfPointBasedAnnotationPointTransformer"/> and updates
''' the <see cref="Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint.FirstPointFillColor"/> and
''' the <see cref="Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint.SecondPointFillColor"/>.
''' </summary>
''' <param name="interactionController">The interaction controller.</param>
''' <param name="firstArcPointColor">The color of the first point of arc annotation.</param>
''' <param name="secondArcPointColor">The color of the second point of arc annotation.</param>
Private Sub SetInteractionPointsColor(interactionController As Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.IWpfInteractionController, firstArcPointColor As System.Windows.Media.Color, secondArcPointColor As System.Windows.Media.Color)
    ' if interaction controller is composite interaction controller
    If TypeOf interactionController Is Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.WpfCompositeInteractionController Then
        Dim compositeInteractionController As Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.WpfCompositeInteractionController = TryCast(interactionController, Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.WpfCompositeInteractionController)

        ' for each interaction controller in composite interaction controller
        For Each item As Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.IWpfInteractionController In compositeInteractionController.Items
            SetInteractionPointsColor(item, firstArcPointColor, secondArcPointColor)
        Next
    End If

    ' if interaction controller is the point-based annotation point transformer
    If TypeOf interactionController Is Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfPointBasedAnnotationPointTransformer Then
        Dim pointTransformer As Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfPointBasedAnnotationPointTransformer = TryCast(interactionController, Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfPointBasedAnnotationPointTransformer)

        If TypeOf pointTransformer.PolygonPointTemplate Is Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint Then
            ' get the interactive point that is used for changing the arc annotation
            Dim arcTransformationInteractionPoint As Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint = DirectCast(pointTransformer.PolygonPointTemplate, Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint)

            ' set color of the first point of arc annotation
            arcTransformationInteractionPoint.FirstPointFillColor = firstArcPointColor
            ' set color of the second point of arc annotation
            arcTransformationInteractionPoint.SecondPointFillColor = secondArcPointColor
        End If
    End If
End Sub

/// <summary>
/// Sets the color for first and second points of WPF arc annotation.
/// </summary>
/// <param name="arcAnnotationView">The WPF arc annotation view.</param>
/// <param name="firstArcPointColor">The color of the first point of arc annotation.</param>
/// <param name="secondArcPointColor">The color of the second point of arc annotation.</param>
public void SetInteractionPointsColor(
    Vintasoft.Imaging.Annotation.Wpf.UI.WpfArcAnnotationView arcAnnotationView,
    System.Windows.Media.Color firstArcPointColor,
    System.Windows.Media.Color secondArcPointColor)
{
    if (arcAnnotationView == null)
        return;

    SetInteractionPointsColor(arcAnnotationView.InteractionController, firstArcPointColor, secondArcPointColor);
}

/// <summary>
/// Finds the <see cref="Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfPointBasedAnnotationPointTransformer"/> and updates
/// the <see cref="Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint.FirstPointFillColor"/> and
/// the <see cref="Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint.SecondPointFillColor"/>.
/// </summary>
/// <param name="interactionController">The interaction controller.</param>
/// <param name="firstArcPointColor">The color of the first point of arc annotation.</param>
/// <param name="secondArcPointColor">The color of the second point of arc annotation.</param>
private void SetInteractionPointsColor(
    Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.IWpfInteractionController interactionController,
    System.Windows.Media.Color firstArcPointColor,
    System.Windows.Media.Color secondArcPointColor)
{
    // if interaction controller is composite interaction controller
    if (interactionController is Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.WpfCompositeInteractionController)
    {
        Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.WpfCompositeInteractionController compositeInteractionController =
            interactionController as Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.WpfCompositeInteractionController;

        // for each interaction controller in composite interaction controller
        foreach (Vintasoft.Imaging.Wpf.UI.VisualTools.UserInteraction.IWpfInteractionController item in compositeInteractionController.Items)
            SetInteractionPointsColor(item, firstArcPointColor, secondArcPointColor);
    }

    // if interaction controller is the point-based annotation point transformer
    if (interactionController is Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfPointBasedAnnotationPointTransformer)
    {
        Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfPointBasedAnnotationPointTransformer pointTransformer =
            interactionController as Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfPointBasedAnnotationPointTransformer;

        if (pointTransformer.PolygonPointTemplate is Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint)
        {
            // get the interactive point that is used for changing the arc annotation
            Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint arcTransformationInteractionPoint =
                (Vintasoft.Imaging.Annotation.Wpf.UI.VisualTools.UserInteraction.WpfArcTransformationInteractionPoint)pointTransformer.PolygonPointTemplate;

            // set color of the first point of arc annotation
            arcTransformationInteractionPoint.FirstPointFillColor = firstArcPointColor;
            // set color of the second point of arc annotation
            arcTransformationInteractionPoint.SecondPointFillColor = secondArcPointColor;
        }
    }
}