Binaryworld - DrawFlipImage - flipping an image on one or both axes ... [ VB.net -> Graphics ]

' Flip an image on one or both axes. The x and y
' parameters are the coordinates of the upper-left point
' Note: requires Imports System.Drawing.Imaging
'
' Example:
' Dim gr As Graphics = Me.CreateGraphics
' gr.Clear(Color.White)
' Dim bmp As New Bitmap("logo.bmp")
' DrawFlipImage(gr, bmp, 100, 20, False, False)
' DrawFlipImage(gr, bmp, 300, 20, True, False)
' DrawFlipImage(gr, bmp, 100, 120, False, True)
' DrawFlipImage(gr, bmp, 300, 120, True, True)
' bmp.Dispose()
' gr.Dispose()

Sub DrawFlipImage(ByVal gr As Graphics, ByVal bmp As Bitmap, ByVal x As Single, _
  ByVal y As Single, ByVal flipX As Boolean, ByVal flipY As Boolean)
  ' Start with values of parallelogram's vertex as if no flipping occurs.
  Dim x0 As Single = x
  Dim y0 As Single = y
  Dim x1 As Single = x + bmp.Width
  Dim y1 As Single = y
  Dim x2 As Single = x
  Dim y2 As Single = y + bmp.Height

  ' Account for horizontal flipping.
  If flipX Then
    x0 = x + bmp.Width
    x1 = x
    x2 = x0
  End If
  ' Account for vertical flipping.
  If flipY Then
    y0 = y + bmp.Height
    y1 = y0
    y2 = y
  End If
  ' Create the points array.
  Dim points() As Point = {New Point(x0, y0), New Point(x1, y1), New Point(x2, _
    y2)}
  ' Draw the flipped image
  gr.DrawImage(bmp, points)
End Sub