cam::pdf::content(3pm) [debian man page]

CAM::PDF::Content(3pm)					User Contributed Perl Documentation				    CAM::PDF::Content(3pm)

NAME

       CAM::PDF::Content - PDF page layout parser

LICENSE

       Same as CAM::PDF

SYNOPSIS

	   use CAM::PDF;
	   my $pdf = CAM::PDF->new($filename);

	   my $contentTree = $pdf->getPageContentTree(4);
	   $contentTree->validate() || die 'Syntax error';
	   print $contentTree->render('CAM::PDF::Renderer::Text');
	   $pdf->setPageContent(5, $contentTree->toString());

DESCRIPTION

       This class is used to manipulate the layout commands for a single page of PDF.  The page content is passed as a scalar and parsed according
       to Adobe's PDF Reference 3rd edition (for PDF v1.4).  All of the commands from Appendix A of that document are parsed and understood.

       Much of the content object's functionality is wrapped up in renderers that can be applied to it.  See the canonical renderer, CAM::PDF::GS,
       and the render() method below for more details.

FUNCTIONS

       $pkg->new($content)
       $pkg->new($content, $data)
       $pkg->new($content, $data, $verbose)
	   Parse a scalar CONTENT containing PDF page layout content.  Returns a parsed, but unvalidated, data structure.

	   The DATA argument is a hash reference of contextual data that may be needed to work with content.  This is only needed for toString()
	   method (which needs "doc => CAM::PDF object" to work with images) and the render methods, to which the DATA reference is passed
	   verbatim.  See the individual renderer modules for details about required elements.

	   The VERBOSE boolean indicates whether the parser should Carp when it encounters problems.  The default is false.

       $self->parse($contentref)
	   This is intended to be called by the new() method.  The argument should be a reference to the content scalar.  It's passed by reference
	   so it is never copied.

       $self->validate()
	   Returns a boolean if the parsed content tree conforms to the PDF specification.

       $self->render($rendererclass)
	   Traverse the content tree using the specified rendering class.  See CAM::PDF::GS or CAM::PDF::Renderer::Text for renderer examples.
	   Renderers should typically derive from CAM::PDF::GS, but it's not essential.  Typically returns an instance of the renderer class.

	   The rendering class is loaded via "require" if not already in memory.

       $self->computeGS()
       $self->computeGS($skiptext)
	   Traverses the content tree and computes the coordinates of each graphic point along the way.  If the $skiptext boolean is true
	   (default: false) then text blocks are ignored to save time, since they do not change the global graphic state.

	   This is a thin wrapper around render() with CAM::PDF::GS or CAM::PDF::GS::NoText selected as the rendering class.

       $self->findImages()
	   Traverse the content tree, accumulating embedded images and image references, according to the CAM::PDF::Renderer::Images renderer.

       $self->traverse($rendererclass)
	   This recursive method is typically called only by wrapper methods, like render().  It instantiates renderers as needed and calls
	   methods on them.

       $self->toString()
	   Flattens a content tree back into a scalar, ready to be inserted back into a PDF document.  Since whitespace is discarded by the
	   parser, the resulting scalar will not be identical to the original.

AUTHOR

       See CAM::PDF

perl v5.14.2							    2012-07-08						    CAM::PDF::Content(3pm)

PDF::API2::Basic::PDF::Objind(3pm)			User Contributed Perl Documentation			PDF::API2::Basic::PDF::Objind(3pm)

NAME

       PDF::API2::Basic::PDF::Objind - PDF indirect object reference. Also acts as an abstract superclass for all elements in a PDF file.

INSTANCE VARIABLES

       Instance variables differ from content variables in that they all start with a space.

       parent
	   For an object which is a reference to an object in some source, this holds the reference to the source object, so that should the
	   reference have to be de-referenced, then we know where to go and get the info.

       objnum (R)
	   The object number in the source (only for object references)

       objgen (R)
	   The object generation in the source

	   There are other instance variables which are used by the parent for file control.

       isfree
	   This marks whether the object is in the free list and available for re-use as another object elsewhere in the file.

       nextfree
	   Holds a direct reference to the next free object in the free list.

METHODS

   PDF::API2::Basic::PDF::Objind->new()
       Creates a new indirect object

   uid
       Returns a Unique id for this object, creating one if it didn't have one before

   $r->release
       Releases ALL of the memory used by this indirect object, and all of its component/child objects.  This method is called automatically by
       '"PDF::API2::Basic::PDF::File->release"' (so you don't have to call it yourself).

       NOTE, that it is important that this method get called at some point prior to the actual destruction of the object.  Internally, PDF files
       have an enormous amount of cross-references and this causes circular references within our own internal data structures.  Calling
       '"release()"' forces these circular references to be cleaned up and the entire internal data structure purged.

       Developer note: As part of the brute-force cleanup done here, this method will throw a warning message whenever unexpected key values are
       found within the "PDF::API2::Basic::PDF::Objind" object.  This is done to help ensure that unexpected and unfreed values are brought to
       your attention, so you can bug us to keep the module updated properly; otherwise the potential for memory leaks due to dangling circular
       references will exist.

   $r->val
       Returns the val of this object or reads the object and then returns its value.

       Note that all direct subclasses *must* make their own versions of this subroutine otherwise we could be in for a very deep loop!

   $r->realise
       Makes sure that the object is fully read in, etc.

   $r->outobjdeep($fh, $pdf)
       If you really want to output this object, then you must need to read it first.  This also means that all direct subclasses must subclass
       this method or loop forever!

   $r->outobj($fh)
       If this is a full object then outputs a reference to the object, otherwise calls outobjdeep to output the contents of the object at this
       point.

   $r->elementsof
       Abstract superclass function filler. Returns self here but should return something more useful if an array.

   $r->empty
       Empties all content from this object to free up memory or to be read to pass the object into the free list. Simplistically undefs all
       instance variables other than object number and generation.

   $r->merge($objind)
       This merges content information into an object reference place-holder.  This occurs when an object reference is read before the object
       definition and the information in the read data needs to be merged into the object place-holder

   $r->is_obj($pdf)
       Returns whether this object is a full object with its own object number or whether it is purely a sub-object. $pdf indicates which output
       file we are concerned that the object is an object in.

   $r->copy($pdf, $res)
       Returns a new copy of this object. The object is assumed to be some kind of associative array and the copy is a deep copy for elements
       which are not PDF objects, according to $pdf, and shallow copy for those that are.  Notice that calling "copy" on an object forces at least
       a one level copy even if it is a PDF object. The returned object loses its PDF object status though.

       If $res is defined then the copy goes into that object rather than creating a new one. It is up to the caller to bless $res, etc. Notice
       that elements from $self are not copied into $res if there is already an entry for them existing in $res.

perl v5.14.2							    2011-03-10					PDF::API2::Basic::PDF::Objind(3pm)