How to create custom triangle annotation?
In This Topic
VintaSoft Annotation .NET Plug-in allows to create custom annotation from scratch, i.e.:
- Create a class, which derives AnnotationData and stores information about annotation data.
- Create a class, which implements IInteractionController interface and defines how the annotation can be built.
- Create a class, which implements IInteractionController interface and defines how the annotation can be transformed.
- Create a class, which derives InteractionPoint and defines a visual appearance of annotation's interactive points, if necessary.
- Create a class, which derives AnnotationView and defines annotation's visual appearance as well as how the user can interact with annotation.
Also Plug-in allows to use any standard annotation as a base class for custom annotation because SDK provides open architecture.
This article describes how to create triangle annotation, which is based on polygon annotation. For doing the task is necessary to create 3 classes:
TriangleAnnotationData class
TriangleAnnotationData class:
- Stores annotation's data (coordinates of triangle vertices) in class properties.
- Serializes annotation's data using the serialization constructor.
- Clones annotation's data using the Clone method.
Here is an example that shows implementation of TriangleAnnotationData class:
Imports System.Drawing
Imports System.Runtime.Serialization
Imports System.Security.Permissions
Imports Vintasoft.Imaging.Annotation
Namespace DemosCommonCode.Annotation
''' <summary>
''' Class that holds information about the annotation that displays a triangle.
''' </summary>
<Serializable> _
Public Class TriangleAnnotationData
Inherits PolygonAnnotationData
#Region "Constructors"
''' <summary>
''' Initializes a new instance of the <see cref="TriangleAnnotationData"/> class.
''' </summary>
Public Sub New()
MyBase.New()
End Sub
''' <summary>
''' Initializes a new instance of the <see cref="TriangleAnnotationData"/> class.
''' </summary>
''' <param name="info">The SerializationInfo to populate with data.</param>
''' <param name="context">The destination for this serialization.</param>
Public Sub New(info As SerializationInfo, context As StreamingContext)
MyBase.New(info, context)
Dim sdkVersion As Integer = 70
If TypeOf context.Context Is Integer Then
sdkVersion = CInt(context.Context)
End If
If sdkVersion < 70 Then
Try
Dim firstPoint As PointF = CType(info.GetValue("FirstPoint", GetType(PointF)), PointF)
Dim secondPoint As PointF = CType(info.GetValue("SecondPoint", GetType(PointF)), PointF)
Dim thirdPoint As PointF = CType(info.GetValue("ThirdPoint", GetType(PointF)), PointF)
Dim points As PointF() = New PointF() {firstPoint, secondPoint, thirdPoint}
Me.Points.ClearAndAddRange(points)
Catch
End Try
'
Me.Location = CType(info.GetValue("Location", GetType(PointF)), PointF)
Me.FillBrush = New AnnotationSolidBrush(Color.Transparent)
Me.Border = True
Me.Outline.DashStyle = AnnotationPenDashStyle.Solid
End If
End Sub
#End Region
#Region "Methods"
''' <summary>
''' Creates a new object that is a copy of the current instance.
''' </summary>
''' <returns>A new object that is a copy of this instance.</returns>
Public Overrides Function Clone() As Object
Dim result As New TriangleAnnotationData()
CopyTo(result)
Return result
End Function
#Region "ISerializable Members"
''' <summary>
''' Populates a SerializationInfo with the data needed to serialize the target object.
''' </summary>
''' <param name="info">The SerializationInfo to populate with data.</param>
''' <param name="context">The destination for this serialization.</param>
<SecurityPermission(SecurityAction.LinkDemand, Flags := SecurityPermissionFlag.SerializationFormatter)> _
Public Overrides Sub GetObjectData(info As SerializationInfo, context As StreamingContext)
If info Is Nothing Then
Throw New ArgumentNullException("info")
End If
Dim sdkVersion As Integer = 70
If TypeOf context.Context Is Integer Then
sdkVersion = CInt(context.Context)
End If
If sdkVersion >= 70 Then
MyBase.GetObjectData(info, context)
Else
info.AddValue("Guid", Me.Guid)
info.AddValue("CreationTime", Me.CreationTime)
info.AddValue("ModifiedTime", Me.ModifiedTime)
info.AddValue("Location", Me.Location)
info.AddValue("Rotation", Me.Rotation)
info.AddValue("Size", Me.Size)
info.AddValue("Visible", Me.IsVisible)
info.AddValue("HorizontalMirrored", Me.HorizontalMirrored)
info.AddValue("VerticalMirrored", Me.VerticalMirrored)
info.AddValue("Border", Me.Border)
info.AddValue("ZOrder", CInt(0))
info.AddValue("BackColor", Color.Black)
info.AddValue("Outline", Me.Outline)
info.AddValue("ToolTip", Me.ToolTip)
If sdkVersion >= 43 Then
info.AddValue("Name", Me.Name)
End If
info.AddValue("FirstPoint", PointF.Empty)
info.AddValue("SecondPoint", PointF.Empty)
info.AddValue("ThirdPoint", PointF.Empty)
End If
End Sub
#End Region
#End Region
End Class
End Namespace
using System;
using System.Drawing;
using System.Runtime.Serialization;
using System.Security.Permissions;
using Vintasoft.Imaging.Annotation;
namespace DemosCommonCode.Annotation
{
/// <summary>
/// Class that holds information about the annotation that displays a triangle.
/// </summary>
[Serializable]
public class TriangleAnnotationData : PolygonAnnotationData
{
#region Constructors
/// <summary>
/// Initializes a new instance of the <see cref="TriangleAnnotationData"/> class.
/// </summary>
public TriangleAnnotationData()
: base()
{
}
/// <summary>
/// Initializes a new instance of the <see cref="TriangleAnnotationData"/> class.
/// </summary>
/// <param name="info">The SerializationInfo to populate with data.</param>
/// <param name="context">The destination for this serialization.</param>
public TriangleAnnotationData(SerializationInfo info, StreamingContext context)
: base(info, context)
{
int sdkVersion = 70;
if (context.Context is int)
sdkVersion = (int)context.Context;
if (sdkVersion < 70)
{
try
{
PointF firstPoint = (PointF)info.GetValue("FirstPoint", typeof(PointF));
PointF secondPoint = (PointF)info.GetValue("SecondPoint", typeof(PointF));
PointF thirdPoint = (PointF)info.GetValue("ThirdPoint", typeof(PointF));
PointF[] points = new PointF[] { firstPoint, secondPoint, thirdPoint };
this.Points.ClearAndAddRange(points);
}
catch
{
}
//
this.Location = (PointF)info.GetValue("Location", typeof(PointF));
this.FillBrush = new AnnotationSolidBrush(Color.Transparent);
this.Border = true;
this.Outline.DashStyle = AnnotationPenDashStyle.Solid;
}
}
#endregion
#region Methods
/// <summary>
/// Creates a new object that is a copy of the current instance.
/// </summary>
/// <returns>A new object that is a copy of this instance.</returns>
public override object Clone()
{
TriangleAnnotationData result = new TriangleAnnotationData();
CopyTo(result);
return result;
}
#region ISerializable Members
/// <summary>
/// Populates a SerializationInfo with the data needed to serialize the target object.
/// </summary>
/// <param name="info">The SerializationInfo to populate with data.</param>
/// <param name="context">The destination for this serialization.</param>
[SecurityPermission(SecurityAction.LinkDemand, Flags = SecurityPermissionFlag.SerializationFormatter)]
public override void GetObjectData(SerializationInfo info, StreamingContext context)
{
if (info == null)
throw new ArgumentNullException("info");
int sdkVersion = 70;
if (context.Context is int)
sdkVersion = (int)context.Context;
if (sdkVersion >= 70)
{
base.GetObjectData(info, context);
}
else
{
info.AddValue("Guid", this.Guid);
info.AddValue("CreationTime", this.CreationTime);
info.AddValue("ModifiedTime", this.ModifiedTime);
info.AddValue("Location", this.Location);
info.AddValue("Rotation", this.Rotation);
info.AddValue("Size", this.Size);
info.AddValue("Visible", this.IsVisible);
info.AddValue("HorizontalMirrored", this.HorizontalMirrored);
info.AddValue("VerticalMirrored", this.VerticalMirrored);
info.AddValue("Border", this.Border);
info.AddValue("ZOrder", (int)0);
info.AddValue("BackColor", Color.Black);
info.AddValue("Outline", this.Outline);
info.AddValue("ToolTip", this.ToolTip);
if (sdkVersion >= 43)
info.AddValue("Name", this.Name);
info.AddValue("FirstPoint", PointF.Empty);
info.AddValue("SecondPoint", PointF.Empty);
info.AddValue("ThirdPoint", PointF.Empty);
}
}
#endregion
#endregion
}
}
TriangleAnnotationInteractionPoint class
TriangleAnnotationInteractionPoint class could have been not implemented, but we had decided to change the appearance of triangle vertices and will do this in this class.
TriangleAnnotationInteractionPoint class:
- Defines appearance of triangle vertices (the vertex will be drawn as large red circle) in class constructor.
- Draws a vertex of rectangle using the Draw method.
- Clones a vertex of rectangle using the Clone method.
Here is an example that shows implementation of TriangleAnnotationInteractionPoint class:
Imports System.Drawing
Imports Vintasoft.Imaging.UI
Imports Vintasoft.Imaging.UI.VisualTools.UserInteraction
Namespace DemosCommonCode.Annotation
''' <summary>
''' Represents rounded interaction point for vertices of triangle annotation.
''' </summary>
Public Class TriangleAnnotationInteractionPoint
Inherits InteractionPolygonPoint
#Region "Constructors"
''' <summary>
''' Initializes a new instance of the <see cref="TriangleAnnotationInteractionPoint"/> class.
''' </summary>
Public Sub New()
MyBase.New("Resize")
BorderColor = Color.Black
FillColor = Color.FromArgb(100, Color.Red)
Radius = 6
End Sub
#End Region
#Region "Methods"
''' <summary>
''' Draws the interaction area on specified graphics.
''' </summary>
''' <param name="viewer">The image viewer.</param>
''' <param name="g">The graphics to draw the interaction area.</param>
Public Overrides Sub Draw(viewer As ImageViewer, g As Graphics)
Dim rect As RectangleF = GetDrawingRect()
If FillBrush IsNot Nothing Then
g.FillEllipse(FillBrush, rect)
End If
If BorderPen IsNot Nothing Then
g.DrawEllipse(BorderPen, rect)
End If
End Sub
''' <summary>
''' Creates a new object that is a copy of the current instance.
''' </summary>
''' <returns>A new object that is a copy of this instance.</returns>
Public Overrides Function Clone() As InteractionArea
Dim area As New TriangleAnnotationInteractionPoint()
CopyTo(area)
Return area
End Function
#End Region
End Class
End Namespace
using System.Drawing;
using Vintasoft.Imaging.UI;
using Vintasoft.Imaging.UI.VisualTools.UserInteraction;
namespace DemosCommonCode.Annotation
{
/// <summary>
/// Represents rounded interaction point for vertices of triangle annotation.
/// </summary>
public class TriangleAnnotationInteractionPoint : InteractionPolygonPoint
{
#region Constructors
/// <summary>
/// Initializes a new instance of the <see cref="TriangleAnnotationInteractionPoint"/> class.
/// </summary>
public TriangleAnnotationInteractionPoint()
: base("Resize")
{
BorderColor = Color.Black;
FillColor = Color.FromArgb(100, Color.Red);
Radius = 6;
}
#endregion
#region Methods
/// <summary>
/// Draws the interaction area on specified graphics.
/// </summary>
/// <param name="viewer">The image viewer.</param>
/// <param name="g">The graphics to draw the interaction area.</param>
public override void Draw(ImageViewer viewer, Graphics g)
{
RectangleF rect = GetDrawingRect();
if (FillBrush != null)
g.FillEllipse(FillBrush, rect);
if (BorderPen != null)
g.DrawEllipse(BorderPen, rect);
}
/// <summary>
/// Creates a new object that is a copy of the current instance.
/// </summary>
/// <returns>A new object that is a copy of this instance.</returns>
public override InteractionArea Clone()
{
TriangleAnnotationInteractionPoint area = new TriangleAnnotationInteractionPoint();
CopyTo(area);
return area;
}
#endregion
}
}
TriangleAnnotationView class
TriangleAnnotationView class:
- Determines that for annotation building is necessary to use standard point based transformer and that the object should contain 3 points.
- Determines that for transforming of annotation as rectangle is necessary to use standard rectangle based transformer.
- Determines that for transforming of annotation as a set of points is necessary to use standard point based transformer, for drawing of vertices should be used TriangleAnnotationInteractionPoint class.
- Clones annotation's appearance using the Clone method.
Here is an example that shows implementation of TriangleAnnotationView class:
Imports System.Drawing
Imports Vintasoft.Imaging.Annotation
Imports Vintasoft.Imaging.Annotation.UI
Imports Vintasoft.Imaging.Annotation.UI.VisualTools.UserInteraction
Namespace DemosCommonCode.Annotation
''' <summary>
''' Class that determines how to display the annotation that displays a triangle
''' and how user can interact with annotation.
''' </summary>
Public Class TriangleAnnotationView
Inherits PolygonAnnotationView
#Region "Constructors"
''' <summary>
''' Initializes a new instance of the <see cref="TriangleAnnotationView"/> class.
''' </summary>
''' <param name="annotationData">Object that stores the annotation data.</param>
Public Sub New(annotationData As TriangleAnnotationData)
MyBase.New(annotationData)
FillBrush = Nothing
' create a point-based builder
Builder = New PointBasedAnnotationPointBuilder(Me, 3, 3)
' create a transformer for rectangular mode
Dim rectangleTransformer As New PointBasedAnnotationRectangularTransformer(Me)
' show bounding box area
rectangleTransformer.BoundingBoxArea.IsVisible = True
RectangularTransformer = rectangleTransformer
' create a transformer for point mode
Dim pointsTransformer As New PointBasedAnnotationPointTransformer(Me)
' change interaction points color
pointsTransformer.InteractionPointBackColor = Color.FromArgb(100, Color.Red)
pointsTransformer.SelectedInteractionPointBackColor = Color.FromArgb(150, Color.Red)
' change interaction points type
pointsTransformer.PolygonPointTemplate = New TriangleAnnotationInteractionPoint()
PointTransformer = pointsTransformer
GripMode = GripMode.RectangularAndPoints
End Sub
#End Region
#Region "Methods"
''' <summary>
''' Creates a new object that is a copy of the current
''' <see cref="TriangleAnnotationView"/> instance.
''' </summary>
''' <returns>A new object that is a copy of this <see cref="TriangleAnnotationView"/>
''' instance.</returns>
Public Overrides Function Clone() As Object
Return New TriangleAnnotationView(DirectCast(Me.Data.Clone(), TriangleAnnotationData))
End Function
#End Region
End Class
End Namespace
using System.Drawing;
using Vintasoft.Imaging.Annotation;
using Vintasoft.Imaging.Annotation.UI;
using Vintasoft.Imaging.Annotation.UI.VisualTools.UserInteraction;
namespace DemosCommonCode.Annotation
{
/// <summary>
/// Class that determines how to display the annotation that displays a triangle
/// and how user can interact with annotation.
/// </summary>
public class TriangleAnnotationView : PolygonAnnotationView
{
#region Constructors
/// <summary>
/// Initializes a new instance of the <see cref="TriangleAnnotationView"/> class.
/// </summary>
/// <param name="annotationData">Object that stores the annotation data.</param>
public TriangleAnnotationView(TriangleAnnotationData annotationData)
: base(annotationData)
{
FillBrush = null;
// create a point-based builder
Builder = new PointBasedAnnotationPointBuilder(this, 3, 3);
// create a transformer for rectangular mode
PointBasedAnnotationRectangularTransformer rectangleTransformer = new PointBasedAnnotationRectangularTransformer(this);
// show bounding box area
rectangleTransformer.BoundingBoxArea.IsVisible = true;
RectangularTransformer = rectangleTransformer;
// create a transformer for point mode
PointBasedAnnotationPointTransformer pointsTransformer = new PointBasedAnnotationPointTransformer(this);
// change interaction points color
pointsTransformer.InteractionPointBackColor = Color.FromArgb(100, Color.Red);
pointsTransformer.SelectedInteractionPointBackColor = Color.FromArgb(150, Color.Red);
// change interaction points type
pointsTransformer.PolygonPointTemplate = new TriangleAnnotationInteractionPoint();
PointTransformer = pointsTransformer;
GripMode = GripMode.RectangularAndPoints;
}
#endregion
#region Methods
/// <summary>
/// Creates a new object that is a copy of the current
/// <see cref="TriangleAnnotationView"/> instance.
/// </summary>
/// <returns>A new object that is a copy of this <see cref="TriangleAnnotationView"/>
/// instance.</returns>
public override object Clone()
{
return new TriangleAnnotationView((TriangleAnnotationData)this.Data.Clone());
}
#endregion
}
}
Register link between TriangleAnnotationData and TriangleAnnotationView classes
Link between TriangleAnnotationData and TriangleAnnotationView classes should be registered before any instance of TriangleAnnotationView class will be created. Link between TriangleAnnotationData and TriangleAnnotationView classes can be registered using the
AnnotationViewFactory.RegisterViewForAnnotationData method.
Examples
The implementation of triangle annotation in C# and VB.NET is a part of AnnotationDemo and WpfAnnotationDemo project code.