Class: Prawn::Core::ObjectStore

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/prawn/core/object_store.rb

Overview

:nodoc:

Constant Summary collapse

BASE_OBJECTS = 
%w[info pages root]

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(opts = {}) ⇒ ObjectStore

Returns a new instance of ObjectStore.



21
22
23
24
25
26
27
28
29
30
31
32
 
# File 'lib/prawn/core/object_store.rb', line 21

def initialize(opts = {})
  @objects = {}
  @identifiers = []

  load_file(opts[:template]) if opts[:template]

  @info  ||= ref(opts[:info] || {}).identifier
  @root  ||= ref(:Type => :Catalog).identifier
  if pages.nil?
    root.data[:Pages] = ref(:Type => :Pages, :Count => 0, :Kids => [])
  end
end

Instance Attribute Details

#min_version ⇒ Object (readonly)

Returns the value of attribute min_version.



17
18
19
 
# File 'lib/prawn/core/object_store.rb', line 17

def min_version
  @min_version
end

Instance Method Details

#[](id) ⇒ Object 



78
79
80
 
# File 'lib/prawn/core/object_store.rb', line 78

def [](id)
  @objects[id]
end

#compact ⇒ Object 



87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
 
# File 'lib/prawn/core/object_store.rb', line 87

def compact
  # Clear live markers
  each { |o| o.live = false }

  # Recursively mark reachable objects live, starting from the roots
  # (the only objects referenced in the trailer)
  root.mark_live
  info.mark_live

  # Renumber live objects to eliminate gaps (shrink the xref table)
  if @objects.any?{ |_, o| !o.live }
    new_id = 1
    new_objects = {}
    new_identifiers = []

    each do |obj|
      if obj.live
        obj.identifier = new_id
        new_objects[new_id] = obj
        new_identifiers << new_id
        new_id += 1
      end
    end

    @objects = new_objects
    @identifiers = new_identifiers
  end
end

#each ⇒ Object 



72
73
74
75
76
 
# File 'lib/prawn/core/object_store.rb', line 72

def each
  @identifiers.each do |id|
    yield @objects[id]
  end
end

#info ⇒ Object 



38
39
40
 
# File 'lib/prawn/core/object_store.rb', line 38

def info
  @objects[@info]
end

#object_id_for_page(k) ⇒ Object

returns the object ID for a particular page in the document. Pages are indexed starting at 1 (not 0!).

object_id_for_page(1)
=> 5
object_id_for_page(10)
=> 87
object_id_for_page(-11)
=> 17



126
127
128
129
130
 
# File 'lib/prawn/core/object_store.rb', line 126

def object_id_for_page(k)
  k -= 1 if k > 0
  flat_page_ids = get_page_objects(pages).flatten
  flat_page_ids[k]
end

#page_count ⇒ Object 



50
51
52
 
# File 'lib/prawn/core/object_store.rb', line 50

def page_count
  pages.data[:Count]
end

#pages ⇒ Object 



46
47
48
 
# File 'lib/prawn/core/object_store.rb', line 46

def pages
  root.data[:Pages]
end

#push(*args, &block) ⇒ Object Also known as: <<

Adds the given reference to the store and returns the reference object. If the object provided is not a Prawn::Core::Reference, one is created from the arguments provided.



58
59
60
61
62
63
64
65
66
67
68
 
# File 'lib/prawn/core/object_store.rb', line 58

def push(*args, &block)
  reference = if args.first.is_a?(Prawn::Core::Reference)
    args.first
  else
    Prawn::Core::Reference.new(*args, &block)
  end

  @objects[reference.identifier] = reference
  @identifiers << reference.identifier
  reference
end

#ref(data, &block) ⇒ Object 



34
35
36
 
# File 'lib/prawn/core/object_store.rb', line 34

def ref(data, &block)
  push(size + 1, data, &block)
end

#root ⇒ Object 



42
43
44
 
# File 'lib/prawn/core/object_store.rb', line 42

def root
  @objects[@root]
end

#size ⇒ Object Also known as: length 



82
83
84
 
# File 'lib/prawn/core/object_store.rb', line 82

def size
  @identifiers.size
end