Blitz Basic Tutes - Image Scanner

Graphics 640,480
SetBuffer BackBuffer()
SeedRnd MilliSecs()
img=LoadImage("hill_castle.jpg")
img_grab=CreateImage(320,240) 
x=Rand(320)
y=Rand(240)
dx=1
dy=1
Repeat
  SetBuffer ImageBuffer(img)
  GrabImage img_grab,x,y
  SetBuffer BackBuffer()
  DrawBlock img_grab,0,0
  Flip
  x=x+dx
  If x<0 Then x=Rand(0,1):dx=1
  If x>320 Then x=320:dx=-1
  y=y+dy
  If y<0 Then y=Rand(0,1):dy=1
  If y>240 Then y=240:dy=-1
Until KeyHit(1)
End