ConvertLogicalToObjectPoints Method

C#
Visual Basic
Objective-C
Java
C++

public AnnPoint[] ConvertLogicalToObjectPoints( 
   AnnPoint[] points
)

'Declaration
 
Public Function ConvertLogicalToObjectPoints( _
   ByVal points() As AnnPoint _
) As AnnPoint()

'Usage
 
Dim instance As AnnObject
Dim points() As AnnPoint
Dim value() As AnnPoint
 
value = instance.ConvertLogicalToObjectPoints(points)

public:
array<AnnPoint>^ ConvertLogicalToObjectPoints( 
   array<AnnPoint>^ points
)

Parameters

points: An array points in logical coordinates.

Return Value

An array of points representing the original array but in object coordinates.

An AnnObject may contain various points, lines, curves and rectangles that denote the object coordinates and where it should be drawn on an image. Also, the AnnObject contains a System.Drawing.Drawing2D.Matrix object that may be updated with a transformation when the object is moved, rotated or sized. This transformation as well as the container's own transformation are used to translate an object point to image coordinates and then to the screen.

The coordinates stored in the object (for example, AnnLineObject.StartPoint or AnnRectangleObject.Bounds are called object coordinates. These coordinates do not translate 1 to 1 to pixel values on the image used in the annotations because of the transformation matrices involved.

The values corresponding to the object coordinates in pixels are called logical coordinates. For example, a logical coordinate of AnnLineObject.StartPoint is its pixel value (in top left-position) in the image it is annotating. Converting from object to logical coordinates is what happens when you call the AnnAutomation.Realize method.

To manipulate an object's position and size manually from outside the annotation framework, you need to first convert its coordinates to logical values, perform your own transformations, convert them back to object coordinates before setting them back to the object.

To convert a point or a group of points from object to logical coordinates, use the ConvertObjectToLogicalPoints method.

To convert a point or a group of points from logical to object coordinates, use the ConvertLogicalToObjectPoints method.

To convert a rectangle from object to logical coordinates, use the ConvertObjectToLogicalRectangle method.

To convert a rectangle from logical to object coordinates, use the ConvertLogicalToObjectRectangle method.

For an example on converting object to logical coordinates, refer to ConvertObjectToLogicalPoints.

This example will offset all the line and rectangle objects to the left by 5 pixels

C#
Visual Basic
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Annotations
Imports Leadtools.Codecs
Imports Leadtools.WinForms
Imports Leadtools.Drawing

Private Sub OffsetLinesAndRectangles(ByVal automation As AnnAutomation)
   ' Loop through all the objects in the annotation container
   For Each annObj As AnnObject In automation.Container.Objects
      If (TypeOf annObj Is AnnLineObject) Then
         Dim lineObj As AnnLineObject = DirectCast(annObj, AnnLineObject)
         ' Move this line object to the left by 5 logical pixels

         ' Convert the line points to logical (image coordinates)
         Dim pts() As AnnPoint = {lineObj.StartPoint, lineObj.EndPoint}

         pts = lineObj.ConvertObjectToLogicalPoints(pts)

         ' Convert the points to pixels
         Dim pt1Pixels As PointF = pts(0).ConvertTo(automation.Container.UnitConverter, AnnUnit.Pixel).ToPointF()
         Dim pt2Pixels As PointF = pts(1).ConvertTo(automation.Container.UnitConverter, AnnUnit.Pixel).ToPointF()

         ' Move them to the right
         pt1Pixels.X -= 5
         pt2Pixels.Y -= 5

         ' Set it back to the line
         pts(0) = New AnnPoint(pt1Pixels, AnnUnit.Pixel)
         pts(1) = New AnnPoint(pt2Pixels, AnnUnit.Pixel)
         pts = lineObj.ConvertLogicalToObjectPoints(pts)
         lineObj.StartPoint = pts(0)
         lineObj.EndPoint = pts(1)
      ElseIf (TypeOf annObj Is AnnRectangleObject) Then
         Dim rectObj As AnnRectangleObject = DirectCast(annObj, AnnRectangleObject)

         ' Yes, get the bounds in pixels

         ' Convert the rectangle bounds to logical (image coordinates)
         Dim bounds As AnnRectangle = rectObj.ConvertObjectToLogicalRectangle(rectObj.Bounds)

         ' Convert the bounds to pixels
         Dim boundsPixels As RectangleF = bounds.ConvertTo(automation.Container.UnitConverter, AnnUnit.Pixel).ToRectangleF()

         ' Move it to the right
         boundsPixels.Offset(-5, 0)

         ' Re-set to bounds
         bounds = rectObj.ConvertLogicalToObjectRectangle(New AnnRectangle(boundsPixels, AnnUnit.Pixel))
         rectObj.Bounds = bounds
      End If
   Next

   ' Invalidate
   automation.Viewer.Invalidate()
End Sub

using Leadtools;
using Leadtools.Annotations;
using Leadtools.Codecs;
using Leadtools.WinForms;
using Leadtools.Drawing;

private void OffsetLinesAndRectangles(AnnAutomation automation)
{
   // Loop through all the objects in the annotation container
   foreach(AnnObject annObj in automation.Container.Objects)
   {
      if(annObj is AnnLineObject)
      {
         AnnLineObject lineObj = annObj as AnnLineObject;
         // Move this line object to the left by 5 logical pixels

         // Convert the line points to logical (image coordinates)
         AnnPoint[] pts = { lineObj.StartPoint, lineObj.EndPoint };

         pts = lineObj.ConvertObjectToLogicalPoints(pts);

         // Convert the points to pixels
         PointF pt1Pixels = pts[0].ConvertTo(automation.Container.UnitConverter, AnnUnit.Pixel).ToPointF();
         PointF pt2Pixels = pts[1].ConvertTo(automation.Container.UnitConverter, AnnUnit.Pixel).ToPointF();

         // Move them to the right
         pt1Pixels.X -= 5;
         pt2Pixels.Y -= 5;

         // Set it back to the line
         pts[0] = new AnnPoint(pt1Pixels, AnnUnit.Pixel);
         pts[1] = new AnnPoint(pt2Pixels, AnnUnit.Pixel);
         pts = lineObj.ConvertLogicalToObjectPoints(pts);
         lineObj.StartPoint = pts[0];
         lineObj.EndPoint = pts[1];
      }
      else if(annObj is AnnRectangleObject)
      {
         AnnRectangleObject rectObj = annObj as AnnRectangleObject;

         // Yes, get the bounds in pixels

         // Convert the rectangle bounds to logical (image coordinates)
         AnnRectangle bounds = rectObj.ConvertObjectToLogicalRectangle(rectObj.Bounds);

         // Convert the bounds to pixels
         RectangleF boundsPixels = bounds.ConvertTo(automation.Container.UnitConverter, AnnUnit.Pixel).ToRectangleF();

         // Move it to the right
         boundsPixels.Offset(-5, 0);

         // Re-set to bounds
         bounds = rectObj.ConvertLogicalToObjectRectangle(new AnnRectangle(boundsPixels, AnnUnit.Pixel));
         rectObj.Bounds = bounds;
      }
   }

   // Invalidate
   automation.Viewer.Invalidate();
}

Target Platforms

Reference

AnnObject Class
AnnObject Members