Module: Prawn::Document::Internals

Included in:
Prawn::Document
Defined in:
lib/prawn/document/internals.rb

Overview

This module exposes a few low-level PDF features for those who want to extend Prawn’s core functionality. If you are not comfortable with low level PDF functionality as defined by Adobe’s specification, chances are you won’t need anything you find here.

Instance Method Summary collapse

Instance Method Details

#add_content(str) ⇒ Object

Appends a raw string to the current page content.

# Raw line drawing example:           
x1,y1,x2,y2 = 100,500,300,550
pdf.add_content("%.3f %.3f m" % [ x1, y1 ])  # move 
pdf.add_content("%.3f %.3f l" % [ x2, y2 ])  # draw path
pdf.add_content("S") # stroke



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# File 'lib/prawn/document/internals.rb', line 37

def add_content(str)
 @page_content << str << "\n"
end

#names ⇒ Object

The Name dictionary (PDF spec 3.6.3) for this document. It is lazily initialized, so that documents that do not need a name dictionary do not incur the additional overhead.



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# File 'lib/prawn/document/internals.rb', line 68

def names
  @root.data[:Names] ||= ref(:Type => :Names)
end

#page_fonts ⇒ Object

The Font dictionary for the current page



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# File 'lib/prawn/document/internals.rb', line 56

def page_fonts
  page_resources[:Font] ||= {}
end

#page_resources ⇒ Object

The Resources dictionary for the current page



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# File 'lib/prawn/document/internals.rb', line 50

def page_resources
  @current_page.data[:Resources] ||= {}
end

#page_xobjects ⇒ Object

The XObject dictionary for the current page



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# File 'lib/prawn/document/internals.rb', line 61

def page_xobjects
  page_resources[:XObject] ||= {}
end

#proc_set(*types) ⇒ Object

Add a new type to the current pages ProcSet



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# File 'lib/prawn/document/internals.rb', line 43

def proc_set(*types)
  @current_page.data[:ProcSet] ||= ref([])
  @current_page.data[:ProcSet].data |= types
end

#ref(data, &block) ⇒ Object

Creates a new Prawn::Reference and adds it to the Document’s object list. The data argument is anything that Prawn::PdfObject() can convert.

If a block is given, it will be invoked just before the object is written out to the PDF document stream. This allows you to do deferred processing on some references (such as fonts, which you might know all the details about until the last page of the document is finished).



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# File 'lib/prawn/document/internals.rb', line 25

def ref(data, &block)
  @objects.push(Prawn::Reference.new(@objects.size + 1, data, &block)).last
end