Module: Prawn::Stamp

Included in:
Document
Defined in:
lib/prawn/stamp.rb

Overview

The Prawn::Stamp module is used to create content that will be included multiple times in a document. Using a stamp has three advantages over creating content anew each time it is placed on the page:

i.   faster document creation
ii.  smaller final document
iii. faster display on subsequent displays of the repeated
element because the viewer application can cache the rendered
results

Example:

pdf.create_stamp("my_stamp") {
  pdf.fill_circle([10, 15], 5)
  pdf.draw_text("hello world", :at => [20, 10])
}
pdf.stamp("my_stamp")

Stable API (collapse)

Instance Method Details

- (Object) create_stamp(name, &block)

Creates a re-usable stamp named name

raises Prawn::Errors::NameTaken if a stamp already exists in this document with this name raises Prawn::Errors::InvalidName if name.empty?

Example:

pdf.create_stamp("my_stamp") {
  pdf.fill_circle([10, 15], 5)
  pdf.draw_text("hello world", :at => [20, 10])
}


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# File 'lib/prawn/stamp.rb', line 78

def create_stamp(name, &block)
  dictionary = create_stamp_dictionary(name)

  state.page.stamp_stream(dictionary, &block)
end

- (Object) stamp(name)

Renders the stamp named name to the page raises Prawn::Errors::InvalidName if name.empty? raises Prawn::Errors::UndefinedObjectName if no stamp has been created with this name

Example:

pdf.create_stamp("my_stamp") {
  pdf.fill_circle([10, 15], 5)
  pdf.text("hello world", :at => [20, 10])
}
pdf.stamp("my_stamp")


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# File 'lib/prawn/stamp.rb', line 42

def stamp(name)
  dictionary_name, dictionary = stamp_dictionary(name)
  renderer.add_content "/#{dictionary_name} Do"
  update_annotation_references dictionary.data[:Annots]
  state.page.xobjects.merge!(dictionary_name => dictionary)
end

- (Object) stamp_at(name, point)

Renders the stamp named name at a position offset from the initial coords at which the elements of the stamp was created

Example:

pdf.create_stamp("circle") do
  pdf.fill_circle([0, 0], 25)
end
# draws a circle at 100, 100
pdf.stamp_at("circle", [100, 100])

See stamp() for exceptions that might be raised



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# File 'lib/prawn/stamp.rb', line 62

def stamp_at(name, point)
  translate(point[0], point[1]) { stamp(name) }
end