'scratchcard' image possible?

The forum is locked. These are the original blitzbasic.com forums, kept so they can still be read. No new topics, replies or edits can be made here. To join in, head over to the Blitz3D+ forums.

Graphics 800, 600
SetBuffer BackBuffer()
Color 0, 0, 0

image1 = LoadImage("image1.png") ;background
image2 = LoadImage("image2.png") ;gray

While Not KeyHit(1)
  If MouseDown(1)
    SetBuffer ImageBuffer(image2)
    Plot MouseX(), MouseY()
    SetBuffer BackBuffer()
  EndIf

  Drawblock image1, 0, 0
  DrawImage image2, 0, 0 ;NOTE the drawIMAGE command
  Flip
Wend