/// <summary>
/// Renders a PDF document with optional content.
/// </summary>
/// <param name="pdfFilename">The PDF filename.</param>
public static void RenderPdfUsingOptonalContent(string pdfFilename)
{
    // get name of output PDF file
    string outputFileName = System.IO.Path.Combine(System.IO.Path.GetDirectoryName(pdfFilename), 
        System.IO.Path.GetFileNameWithoutExtension(pdfFilename));
    outputFileName = outputFileName + "_{0}_{1}.tif";

    // open document stream
    using (System.IO.Stream documentStream = 
        System.IO.File.Open(pdfFilename, System.IO.FileMode.Open))
    {
        // create image collection, which will store pages of PDF document
        using (Vintasoft.Imaging.ImageCollection documentImages = 
            new Vintasoft.Imaging.ImageCollection())
        {
            // add document pages to the image collection
            documentImages.Add(documentStream);

            // open PDF document
            Vintasoft.Imaging.Pdf.PdfDocument document = 
                Vintasoft.Imaging.Pdf.PdfDocumentController.OpenDocument(documentStream);

            // if document does not have optional content
            if (document.OptionalContentProperties == null)
            {
                System.Console.WriteLine("Document does not have optional content.");
                return;
            }

            // if PDF document has the default optional content configuration
            if (document.OptionalContentProperties.DefaultConfiguration != null)
            {
                // set the default optional content configuration as current optional content configuration
                document.OptionalContentConfiguration = document.OptionalContentProperties.DefaultConfiguration;
                // render PDF pages and save them to a multipage TIFF file
                SaveImages(documentImages, string.Format(outputFileName, "defaultConfig", document.OptionalContentConfiguration.Name));
            }

            // if PDF document has a list of optional content configurations
            if (document.OptionalContentProperties.Configurations != null)
            {
                // for each optional content configuration
                foreach (Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration config in
                    document.OptionalContentProperties.Configurations)
                {
                    // set the optional content configuration as current optional content configuration
                    document.OptionalContentConfiguration = config;
                    // render PDF pages and save them to a multipage TIFF file
                    SaveImages(documentImages, string.Format(outputFileName, "config", config.Name));
                }
            }


            // create custom optional content configuration
            Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration myConfig =
                new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "MyConfig");
            // create an empty list of optional content groups whose state should
            // be set to ON when this configuration is applied
            myConfig.OnGroups =
                new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroupList(document);
            // specify that optional content groups are "Off" by default
            myConfig.BaseState =
                Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfigurationBaseState.Off;
            // set custom optional content configuration as
            // current optional content configuration of PDF document
            document.OptionalContentConfiguration = myConfig;
            // for each optional content group of PDF document
            foreach (Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup 
                group in document.OptionalContentProperties.OptionalContentGroups)
            {
                // clear list of "On" groups, i.e. specify that groups must be not visible
                myConfig.OnGroups.Clear();
                // add group to the list of "On" groups, i.e. specify that group must be visible
                myConfig.OnGroups.Add(group);
                // render PDF pages and save them to a file
                SaveImages(documentImages, string.Format(outputFileName, "group", group.Name));
            }


            // close PDF document
            Vintasoft.Imaging.Pdf.PdfDocumentController.CloseDocument(document);

            // free resources
            documentImages.ClearAndDisposeItems();
        }
    }
}

/// <summary>
/// Saves images (PDF pages) to the specified file.
/// </summary>
/// <param name="images">The image collection.</param>
/// <param name="filename">The filename where image collection must be saved.</param>
private static void SaveImages(Vintasoft.Imaging.ImageCollection images, string filename)
{
    // create encoder
    using (Vintasoft.Imaging.Codecs.Encoders.MultipageEncoderBase encoder = 
        Vintasoft.Imaging.Codecs.Encoders.AvailableEncoders.CreateMultipageEncoder(filename))
    {
        // set rendering settings
        images.SetRenderingSettings(new Vintasoft.Imaging.Codecs.Decoders.RenderingSettings(
            new Vintasoft.Imaging.Resolution(300, 300)));

        // specify that image collection should not be switched to new file
        encoder.SaveAndSwitchSource = false;
        // save images to a file
        images.SaveSync(filename, encoder);
    }
}

''' <summary>
''' Renders a PDF document with optional content.
''' </summary>
''' <param name="pdfFilename">The PDF filename.</param>
Public Shared Sub RenderPdfUsingOptonalContent(pdfFilename As String)
    ' get name of output PDF file
    Dim outputFileName As String = System.IO.Path.Combine(System.IO.Path.GetDirectoryName(pdfFilename), System.IO.Path.GetFileNameWithoutExtension(pdfFilename))
    outputFileName = outputFileName & "_{0}_{1}.tif"

    ' open document stream
    Using documentStream As System.IO.Stream = System.IO.File.Open(pdfFilename, System.IO.FileMode.Open)
        ' create image collection, which will store pages of PDF document
        Using documentImages As New Vintasoft.Imaging.ImageCollection()
            ' add document pages to the image collection
            documentImages.Add(documentStream)

            ' open PDF document
            Dim document As Vintasoft.Imaging.Pdf.PdfDocument = Vintasoft.Imaging.Pdf.PdfDocumentController.OpenDocument(documentStream)

            ' if document does not have optional content
            If document.OptionalContentProperties Is Nothing Then
                System.Console.WriteLine("Document does not have optional content.")
                Return
            End If

            ' if PDF document has the default optional content configuration
            If document.OptionalContentProperties.DefaultConfiguration IsNot Nothing Then
                ' set the default optional content configuration as current optional content configuration
                document.OptionalContentConfiguration = document.OptionalContentProperties.DefaultConfiguration
                ' render PDF pages and save them to a multipage TIFF file
                SaveImages(documentImages, String.Format(outputFileName, "defaultConfig", document.OptionalContentConfiguration.Name))
            End If

            ' if PDF document has a list of optional content configurations
            If document.OptionalContentProperties.Configurations IsNot Nothing Then
                ' for each optional content configuration
                For Each config As Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration In document.OptionalContentProperties.Configurations
                    ' set the optional content configuration as current optional content configuration
                    document.OptionalContentConfiguration = config
                    ' render PDF pages and save them to a multipage TIFF file
                    SaveImages(documentImages, String.Format(outputFileName, "config", config.Name))
                Next
            End If


            ' create custom optional content configuration
            Dim myConfig As New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "MyConfig")
            ' create an empty list of optional content groups whose state should
            ' be set to ON when this configuration is applied
            myConfig.OnGroups = New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroupList(document)
            ' specify that optional content groups are "Off" by default
            myConfig.BaseState = Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfigurationBaseState.Off
            ' set custom optional content configuration as
            ' current optional content configuration of PDF document
            document.OptionalContentConfiguration = myConfig
            ' for each optional content group of PDF document
            For Each group As Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup In document.OptionalContentProperties.OptionalContentGroups
                ' clear list of "On" groups, i.e. specify that groups must be not visible
                myConfig.OnGroups.Clear()
                ' add group to the list of "On" groups, i.e. specify that group must be visible
                myConfig.OnGroups.Add(group)
                ' render PDF pages and save them to a file
                SaveImages(documentImages, String.Format(outputFileName, "group", group.Name))
            Next


            ' close PDF document
            Vintasoft.Imaging.Pdf.PdfDocumentController.CloseDocument(document)

            ' free resources
            documentImages.ClearAndDisposeItems()
        End Using
    End Using
End Sub

''' <summary>
''' Saves images (PDF pages) to the specified file.
''' </summary>
''' <param name="images">The image collection.</param>
''' <param name="filename">The filename where image collection must be saved.</param>
Private Shared Sub SaveImages(images As Vintasoft.Imaging.ImageCollection, filename As String)
    ' create encoder
    Using encoder As Vintasoft.Imaging.Codecs.Encoders.MultipageEncoderBase = Vintasoft.Imaging.Codecs.Encoders.AvailableEncoders.CreateMultipageEncoder(filename)
        ' set rendering settings
        images.SetRenderingSettings(New Vintasoft.Imaging.Codecs.Decoders.RenderingSettings(New Vintasoft.Imaging.Resolution(300, 300)))

        ' specify that image collection should not be switched to new file
        encoder.SaveAndSwitchSource = False
        ' save images to a file
        images.SaveSync(filename, encoder)
    End Using
End Sub

/// <summary>
/// Creates PDF document with the optional content.
/// </summary>
/// <param name="pdfFilename">The PDF filename.</param>
public static void CreateDocumentWithOptionalContent(string pdfFilename)
{
    // create new PDF document
    using (Vintasoft.Imaging.Pdf.PdfDocument document = 
        new Vintasoft.Imaging.Pdf.PdfDocument(pdfFilename, Vintasoft.Imaging.Pdf.PdfFormat.Pdf_16))
    {
        // add empty page (A4 size)
        Vintasoft.Imaging.Pdf.Tree.PdfPage page = document.Pages.Add(
            Vintasoft.Imaging.PaperSizeKind.A4);

        // create two optional content groups
        Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup layer1 =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup(document, "Layer1");
        Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup layer2 =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup(document, "Layer2");

        // add optional content groups to OptionalContentProperties
        document.OptionalContentProperties =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentProperties(document);
        document.OptionalContentProperties.OptionalContentGroups.Add(layer1);
        document.OptionalContentProperties.OptionalContentGroups.Add(layer2);

        // get PdfGraphics for PDF page
        using (Vintasoft.Imaging.Pdf.Drawing.PdfGraphics g = page.GetGraphics())
        {
            Vintasoft.Imaging.Pdf.Tree.Fonts.PdfFont font = document.FontManager.GetStandardFont(
                Vintasoft.Imaging.Pdf.Tree.Fonts.PdfStandardFontType.TimesRoman);
            Vintasoft.Imaging.Pdf.Drawing.PdfBrush brush = new Vintasoft.Imaging.Pdf.Drawing.PdfBrush(
                System.Drawing.Color.Black);
            Vintasoft.Imaging.Pdf.Drawing.PdfBrush brush1 = new Vintasoft.Imaging.Pdf.Drawing.PdfBrush(
                System.Drawing.Color.Green);
            Vintasoft.Imaging.Pdf.Drawing.PdfBrush brush2 = new Vintasoft.Imaging.Pdf.Drawing.PdfBrush(
                System.Drawing.Color.Red);

            // draw not optional content
            g.DrawString("Not optional content", font, 20, brush, new System.Drawing.PointF(50, 650));

            // draw optional content "Layer1"
            g.BeginOptionalContent(layer1);
            g.DrawString(string.Format("Optional content '{0}'", layer1.Name),
                font, 25, brush1, new System.Drawing.PointF(50, 550));
            g.EndOptionalContent();

            // draw not optional content
            g.DrawString("Not optional content", font, 30, brush, new System.Drawing.PointF(50, 450));

            // draw optional content "Layer2"
            g.BeginOptionalContent(layer2);
            g.DrawString(string.Format("Optional content '{0}'", layer2.Name),
                font, 35, brush2, new System.Drawing.PointF(50, 350));
            g.EndOptionalContent();

            // draw not optional content
            g.DrawString("Not optional content", font, 40, brush, new System.Drawing.PointF(50, 250));
        }

        // create optional content configurations
        Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration configuration1 =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "Layer1 and Layer2");
        configuration1.SetGroupVisibility(layer1, true);
        configuration1.SetGroupVisibility(layer2, true);
        Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration configuration2 =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "Layer1");
        configuration2.SetGroupVisibility(layer1, true);
        configuration2.SetGroupVisibility(layer2, false);
        Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration configuration3 =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "Layer2");
        configuration3.SetGroupVisibility(layer1, false);
        configuration3.SetGroupVisibility(layer2, true);
        Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration configuration4 =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "No Layers");
        configuration4.SetGroupVisibility(layer1, false);
        configuration4.SetGroupVisibility(layer2, false);

        // create list of optional content configuration
        document.OptionalContentProperties.Configurations =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfigurationList(document);

        // add configurations to list
        document.OptionalContentProperties.Configurations.Add(configuration1);
        document.OptionalContentProperties.Configurations.Add(configuration2);
        document.OptionalContentProperties.Configurations.Add(configuration3);
        document.OptionalContentProperties.Configurations.Add(configuration4);

        // set default configuration
        document.OptionalContentProperties.DefaultConfiguration = configuration1;

        // set presentation order
        configuration1.PresentationOrder =
            new Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentPresentationOrder(document, layer1, layer2);

        // optional content panel is visible
        document.DocumentViewMode = Vintasoft.Imaging.Pdf.PdfDocumentViewMode.UseOC;

        // save changes in PDF document
        document.SaveChanges();
    }
}

''' <summary>
''' Creates PDF document with the optional content.
''' </summary>
''' <param name="pdfFilename">The PDF filename.</param>
Public Shared Sub CreateDocumentWithOptionalContent(pdfFilename As String)
    ' create new PDF document
    Using document As New Vintasoft.Imaging.Pdf.PdfDocument(pdfFilename, Vintasoft.Imaging.Pdf.PdfFormat.Pdf_16)
        ' add empty page (A4 size)
        Dim page As Vintasoft.Imaging.Pdf.Tree.PdfPage = document.Pages.Add(Vintasoft.Imaging.PaperSizeKind.A4)

        ' create two optional content groups
        Dim layer1 As New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup(document, "Layer1")
        Dim layer2 As New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentGroup(document, "Layer2")

        ' add optional content groups to OptionalContentProperties
        document.OptionalContentProperties = New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentProperties(document)
        document.OptionalContentProperties.OptionalContentGroups.Add(layer1)
        document.OptionalContentProperties.OptionalContentGroups.Add(layer2)

        ' get PdfGraphics for PDF page
        Using g As Vintasoft.Imaging.Pdf.Drawing.PdfGraphics = page.GetGraphics()
            Dim font As Vintasoft.Imaging.Pdf.Tree.Fonts.PdfFont = document.FontManager.GetStandardFont(Vintasoft.Imaging.Pdf.Tree.Fonts.PdfStandardFontType.TimesRoman)
            Dim brush As New Vintasoft.Imaging.Pdf.Drawing.PdfBrush(System.Drawing.Color.Black)
            Dim brush1 As New Vintasoft.Imaging.Pdf.Drawing.PdfBrush(System.Drawing.Color.Green)
            Dim brush2 As New Vintasoft.Imaging.Pdf.Drawing.PdfBrush(System.Drawing.Color.Red)

            ' draw not optional content
            g.DrawString("Not optional content", font, 20, brush, New System.Drawing.PointF(50, 650))

            ' draw optional content "Layer1"
            g.BeginOptionalContent(layer1)
            g.DrawString(String.Format("Optional content '{0}'", layer1.Name), font, 25, brush1, New System.Drawing.PointF(50, 550))
            g.EndOptionalContent()

            ' draw not optional content
            g.DrawString("Not optional content", font, 30, brush, New System.Drawing.PointF(50, 450))

            ' draw optional content "Layer2"
            g.BeginOptionalContent(layer2)
            g.DrawString(String.Format("Optional content '{0}'", layer2.Name), font, 35, brush2, New System.Drawing.PointF(50, 350))
            g.EndOptionalContent()

            ' draw not optional content
            g.DrawString("Not optional content", font, 40, brush, New System.Drawing.PointF(50, 250))
        End Using

        ' create optional content configurations
        Dim configuration1 As New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "Layer1 and Layer2")
        configuration1.SetGroupVisibility(layer1, True)
        configuration1.SetGroupVisibility(layer2, True)
        Dim configuration2 As New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "Layer1")
        configuration2.SetGroupVisibility(layer1, True)
        configuration2.SetGroupVisibility(layer2, False)
        Dim configuration3 As New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "Layer2")
        configuration3.SetGroupVisibility(layer1, False)
        configuration3.SetGroupVisibility(layer2, True)
        Dim configuration4 As New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfiguration(document, "No Layers")
        configuration4.SetGroupVisibility(layer1, False)
        configuration4.SetGroupVisibility(layer2, False)

        ' create list of optional content configuration
        document.OptionalContentProperties.Configurations = New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentConfigurationList(document)

        ' add configurations to list
        document.OptionalContentProperties.Configurations.Add(configuration1)
        document.OptionalContentProperties.Configurations.Add(configuration2)
        document.OptionalContentProperties.Configurations.Add(configuration3)
        document.OptionalContentProperties.Configurations.Add(configuration4)

        ' set default configuration
        document.OptionalContentProperties.DefaultConfiguration = configuration1

        ' set presentation order
        configuration1.PresentationOrder = New Vintasoft.Imaging.Pdf.Tree.OptionalContent.PdfOptionalContentPresentationOrder(document, layer1, layer2)

        ' optional content panel is visible
        document.DocumentViewMode = Vintasoft.Imaging.Pdf.PdfDocumentViewMode.UseOC

        ' save changes in PDF document
        document.SaveChanges()
    End Using
End Sub