OpenLibrary MACRO
  MOVE.L $4,A6
  MOVE.L #\1,A1
  MOVE.L #\2,D0
  CALLLIB _LVOOpenLibrary
  ENDM
  
  INCLUDE "graphics/gfxbase.i"
  INCLUDE "graphics_lvo.i" ; requires fd2pragma to create
  INCLUDE "exec/exec_lib.i"
  
; preserve registers code is below
  
PreserveViewAndCopperList:
  OpenLibrary GraphicsLibrary,0
  MOVE.L D0,GraphicsBase
  MOVE.L D0,A6  

  MOVE.L gb_ActiView(A6),OldView
  MOVE.L gb_copinit(A6),OldCopper

TakeOwnership:
  MOVE.L #0,A1
  CALLLIB _LVOLoadView ; nuke the view
  CALLLIB _LVOWaitTOF     ; wait two vertical blanks
  CALLLIB _LVOWaitTOF
  CALLLIB _LVOOwnBlitter
  CALLLIB _LVOWaitBlit    ; wait...

  MOVE.L $4,A6
  CALLLIB _LVOForbid ; the system is ours
  
  CNOP 0,4
OldView   dc.l 0
OldCopper dc.l 0
GraphicsBase dc.l 0

  CNOP 0,4
GraphicsLibrary GRAPHICSNAME