Class: PSD::Descriptor

Inherits:
Object
  • Object
show all
Defined in:
lib/psd/descriptor.rb

Overview

A descriptor is a block of data that describes a complex data structure of some kind. It was added sometime around Photoshop 5.0 and it superceded a few legacy things such as layer names and type data.

Instance Method Summary collapse

Constructor Details

#initialize(file) ⇒ Descriptor

Store a reference to our file and initialize our data structure.



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# File 'lib/psd/descriptor.rb', line 7

def initialize(file)
  @file = file
  @data = {}
end

Instance Method Details

#parse ⇒ Object

Parse the descriptor. Descriptors always start with a class identifier, followed by a variable number of items in the descriptor. We return the Hash that represents the full data structure.



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# File 'lib/psd/descriptor.rb', line 15

def parse
  PSD.logger.debug "Descriptor: pos = #{@file.tell}"

  @data[:class] = parse_class
  num_items = @file.read_int

  PSD.logger.debug "Class = #{@data[:class]}, Item count = #{num_items}"

  num_items.times do |i|
    id, value = parse_key_item
    @data[id] = value
  end

  @data
end