reference.rb in prawn-0.1.2

- old
+ new

@@ -4,10 +4,12 @@
 #
 # Copyright April 2008, Gregory Brown.  All Rights Reserved.
 #
 # This is free software. Please see the LICENSE and COPYING files for details.
 
+require 'zlib'
+
 module Prawn  
   
   class Reference #:nodoc:
              
    attr_accessor :gen, :data, :offset
@@ -15,10 +17,11 @@
     
     def initialize(id,data)
       @identifier = id 
       @gen   = 0       
       @data  = data     
+      @compressed = false
     end            
     
     def object 
       output = "#{@identifier} #{gen} obj\n" <<
                Prawn::PdfObject(data) << "\n"
@@ -27,16 +30,22 @@
       end
       output << "endobj\n"
     end  
     
     def <<(data)
+      raise 'Cannot add data to a stream that is compressed' if @compressed
       (@stream ||= "") << data  
     end  
     
     def to_s            
       "#{@identifier} #{gen} R"
     end
-      
+
+    def compress_stream
+      @stream = Zlib::Deflate.deflate(@stream)
+      @data[:Filter] = :FlateDecode
+      @compressed = true
+    end
   end         
   
   module_function
   
   def Reference(*args) #:nodoc: