nulldev.ps

/QUIET where { pop }{ (loading nulldev.ps...)print } ifelse

/DEVICE { graphicsdict /currgstate get /device get } def
/nulldevice {
    graphicsdict /currgstate get /device
    612 792 newnulldevice
    put
} def
/newnulldevice { % width height
    NULLDEV dup /Create get exec
} def

% NULLDEV device implements the "nulldevice", which
% does no drawing, but otherwise performs all graphics operations
% and will return appropriately-transformed graphics state parameters.
%
% In the list of procedures below, PGMIMAGE is the Class dictionary,
% IMAGE is an instance returned by Create.
% The nulldevice implementations of these methods
% merely have to consume these arguments from the stack
% using `pop`.
%
% procedures:
%           width height PGMIMAGE  Create  ->  IMAGE
%                   val x y IMAGE  PutPix  ->  -
%                       x y IMAGE  GetPix  ->  val
%           val x1 y1 x2 y2 IMAGE  DrawLine  ->  -
%      val x y width height IMAGE  DrawRect  ->  -
%      val x y width height IMAGE  FillRect  ->  -
%               val polygon IMAGE  FillPoly  ->  -
%                           IMAGE  Emit  ->  -
%                           IMAGE  Destroy  ->  -
%                           dict1  .copydict  dict2
%

/NULLDEV <<
    /nativecolorspace /DeviceGray
    /dimensions [0 0]

    /.copydict {
        dup length dict copy
        dup /width known {
            dup begin
                /dimensions [width height] def
            end
        } if
    }
    /Create { % width height IMAGE  .  IMAGE'
        begin {/height /width}{exch def}forall
        currentdict end
        dup /.copydict get exec
    }

    /Destroy { % IMAGE  .  -
        pop
    } 

    /PutPix { % val x y IMAGE  .  -
        pop pop pop pop
    }

    /GetPix { % x y IMAGE  .  val
        pop pop pop  0
    }

    /DrawLine { % val x1 y1 x2 y2 IMAGE  .  -
        pop pop pop pop pop pop
    }

    /DrawRect { % val x y w h IMAGE  .  -
        pop pop pop pop pop pop
    }

    /FillRect { % val x y w h IMAGE  .  -
        pop pop pop pop pop pop
    }

    /FillPoly { % val polygon IMAGE  .  -
        pop pop pop
    } 

    /Emit {
        pop
    }
>> def

/QUIET where { pop }{ (eof nulldev.ps\n)print } ifelse