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ConvertLogicalToObjectPoints Method
See Also 
Leadtools.Annotations Namespace > AnnObject Class : ConvertLogicalToObjectPoints Method



points
An array points in logical coordinates.
points
An array points in logical coordinates.
Converts an array of points from logical to object coordinates.

Syntax

Visual Basic (Declaration) 
Public Function ConvertLogicalToObjectPoints( _
   ByVal points() As AnnPoint _
) As AnnPoint()
Visual Basic (Usage)Copy Code
Dim instance As AnnObject
Dim points() As AnnPoint
Dim value() As AnnPoint
 
value = instance.ConvertLogicalToObjectPoints(points)
C# 
public AnnPoint[] ConvertLogicalToObjectPoints( 
   AnnPoint[] points
)
C++/CLI 
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.

Example

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

Visual BasicCopy Code
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
C#Copy Code
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();
}

Remarks

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.

Requirements

Target Platforms: Microsoft .NET Framework 2.0, Windows 2000, Windows XP, Windows Server 2003 family, Windows Server 2008 family, Windows Vista, Windows 7

See Also

Leadtools.Annotations requires a Document or Medical toolkit license and unlock key. For more information, refer to: Imaging Pro/Document/Medical Features