Annotation performance

I'm trying to use annotations, with VB2005 and FW2.0. To start my job I'm looking at your example VBAutomationDemo. One of the most important feature I need is to put on an image many annotations (also 500 annotations). The example work fine, and it demonstrate the functionality I need, but with many object the application goes slowly. If I try to select an annotation, only select, it respond after some seconds and if try to move the annotation all proceed slowly. The hardware performance is very high and doing tests I understand that the problem is not a performance problem. Can you help me,  is there some recursively event fired whenever I move or some property to disable some function not needed?

Thanks.

Hi Maen,

the problem is always visible, also if I restart the pc and I run immediatly the application, other application running on the pc are not affected by any performance problem. Even if the application with 500 annotation take over 600-700 MB of Ram, I've 2GB installed on the pc.
In the attached example I use the automation manager with toolbar and then I add 500 stamps manually. If you try to select one stamp and move it in the container you can see how slow it is. Try also with 50 stamps. you'll se the difference. In my application I don't need to use the automation manager and the toolbar, for me is just ok to add stamps or any other object manually like in the example attached. Do you think automation manager uses many resources and for thi is so slow?

Thanks!!!!!!!!

File Attachment(s):

WindowsApplication1.zip (529kb) downloaded 34 time(s).

Hi Maen,

I understand which is the problem! Every time I select  or I  move an annotation the method Draw of the annotation container is called for refresh the image, but in the draw method as you can see below there'a a loop that force the redraw of every annotation.

Public Overridable Sub Draw(ByVal g As Graphics)
      If Me.Visible Then
            Dim state1 As GraphicsState = g.Save
            Using region1 As Region = New Region(Me.BoundsPixels)
                  If (Not Me.Transform Is Nothing) Then
                        region1.Transform(Me.Transform)
                  End If
                  g.Clip = region1
            End Using
            If (Me._ignoreDrawObjectEvents <= 0) Then
                  Me.OnBeforeDrawingObjects(New AnnPaintEventArgs(g))
            End If
            Dim obj1 As AnnObject
            For Each obj1 In Me.Objects
                  obj1.Draw(g)
            Next
            If (Me._ignoreDrawObjectEvents <= 0) Then
                  Me.OnAfterDrawingObjects(New AnnPaintEventArgs(g))
            End If
            g.Restore(state1)
      End If
End Sub

This method is called in the PostTransformPaint event of them ImageViewer, and if I don't implement it the annotation are not redrawn! How can optimize this event? Can I Force the redraw only when I need and which is the best moment to do this?

Thanks!