How do I release a handle to a GDI region in a pointer array?

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VB

GDI

In my app I paint rectangles on a picturebox in diferent locations. I can drag them around with the mouse and even rotate them with the mouse wheel.

At first I used pictureboxes, but rotating them became a hassle, so I created my own class instead. My class holds the drawing point points of the object and in the paint event I create paths from these points and paint them.

To get mouse event I created regions in the paint event and stored them in a pointer array so I can use

PtInRegion()

to check if a mouse is over an object.

Great it all works. Object are painted, moved and rotated. I only needed to do the math for scaling the whole lot but then i got an out of memmory error.

What I have tried:

Using Process Explorer I traced the problem to this line:

ptrRegion(sx) = rgn.GetHrgn(g)

This is where I store a handle to the region in a pointer array.
In Proccess Explorer my GDI handle count skyrockets every time I move the objects.
Comenting the line out solves the GDI Handle problem but then I cannot drag the objects anymore.
Here is my paint event:

Try
	Dim g As Graphics = e.Graphics
   
	For Each Drop As MyPictureBox In DropList
		With Drop
			Dim sx As Integer
			sx = .ArrayIndex   'array index of drop 

			Dim mypath, fillPath As New System.Drawing.Drawing2D.GraphicsPath
			Dim curvepoints As Point() = {.BorderPoint1, .BorderPoint2, .BorderPoint3, .BorderPoint4}
			Dim fillPoint As Point() = {.FillPoint1, .FillPoint2, .FillPoint3, .FillPoint4}
			Dim rPoint = .DrawCentre

			mypath.AddPolygon(curvepoints)
			fillPath.AddPolygon(fillPoint)

			Dim mymatrix As New System.Drawing.Drawing2D.Matrix
			mymatrix.RotateAt(.ShelfRotation, rPoint)
			mypath.Transform(mymatrix)
			fillPath.Transform(mymatrix)

			Dim rgn As System.Drawing.Region
			rgn = New Region(mypath)
		  
			'If ptrRegion(sx) = 0 Then
			ptrRegion(sx) = rgn.GetHrgn(g) 'if I comment this line out promblem disappears but I cannot move the objects anymore.
			'End If
			
			g.FillPath(.BorderSolidBrush, mypath)
			g.FillPath(.FillSolidBrush, fillPath)

			rgn.Dispose()
			mypath.Dispose()
			fillPath.Dispose()
			mymatrix.Dispose()
		End With
	Next
   
Catch ex As Exception
	MsgBox("Error:" & ex.ToString)
End Try

And on mouse move:

Private Sub picFloor_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles picFloor.MouseMove
	lblCoordinates.Text = "Mouse is at X: " & e.X & " Y: " & e.Y

	Dim id As Integer
	id = 9999 'mouse pointing at background
	For Each Drop As MyPictureBox In DropList
		Dim x As Integer
		x = Drop.ArrayIndex
		If (PtInRegion(ptrRegion(x), e.X, e.Y)) Then
			id = x 'mouse is pointing to an object
			picFloor.ContextMenuStrip = rightClickMenu
			Exit For
		End If
	Next
	mouseOverID = id
	lblmouseid.Text = mouseOverID

	If drag = True Then
		picFloor.ContextMenuStrip = Nothing
		'Scroll the map on mouse right button
		If e.Button = Windows.Forms.MouseButtons.Right Then
			Dim DeltaX As Integer = (startPos.X - e.X)
			Dim DeltaY As Integer = (startPos.Y - e.Y)
			'Set the new autoscroll position.
			DropPannel.AutoScrollPosition = New Drawing.Point((DeltaX - DropPannel.AutoScrollPosition.X), (DeltaY - DropPannel.AutoScrollPosition.Y))
			panelScrollPoss = New Drawing.Point((DeltaX - DropPannel.AutoScrollPosition.X), (DeltaY - DropPannel.AutoScrollPosition.Y))
		End If

		'Drag the shelf on left button
		If (dragID <> 9999) Then
			If e.Button = Windows.Forms.MouseButtons.Left Then
				Dim Drop As MyPictureBox = DropList.Find(Function(c) c.ArrayIndex = dragID)
				If Drop.PositionLocked = False Then
					Dim diference = New Point(e.X - startPos.X, e.Y - startPos.Y) 'distance that the mouse moved.					
					Drop.DrawCentre = New Point(startPos.X + diference.X - mouseOfset.X, startPos.Y + diference.Y - mouseOfset.Y)
					Drop.SetCentrePoint()
					Me.Refresh()
				End If
			End If
		End If
	Else
		picFloor.Focus()
		DropPannel.AutoScrollPosition = panelScrollPoss 'Return scrollbars to its last position
	End If
End Sub

I tried to use region.translate instead of creating a new region every time, but couldn't figure it out. Can anyone please tell me how do I release the DGI handles? In my code at the end of the paint event, I dispose of everything I used but the GDI handle count still maxes when I move the map or othe objects on it.