Module: JazzModel::ToneSequence

Defined in:
lib/jazz_model/tone_sequence.rb

Overview

This module is mixed in wherever a collection of tones is being returned and handles some of the fundamental logic involved in key and mode calculations and note values.

Instance Method Summary collapse

Instance Method Details

#all ⇒ Object

TODO: Have to use this until we figure out how to override find/default collection result



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# File 'lib/jazz_model/tone_sequence.rb', line 47

def all
	in_key_context! if key
	in_mode_context! if mode
	self.sort_by(&:position)
end

#in_key_context! ⇒ Object

Shifts indexes to simulate a key change



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# File 'lib/jazz_model/tone_sequence.rb', line 20

def in_key_context!
	self.each do |tone| 
		tone.tone = (tone.tone + key.index) % 12
		tone.letter_index = (tone.letter_index + key.letter_index) % 7
	end
	true
end

#in_key_of(in_key = nil) ⇒ Object

Manually specifies the key context for this tone sequence only.



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# File 'lib/jazz_model/tone_sequence.rb', line 14

def in_key_of(in_key = nil)
	@key = in_key.instance_of?(String) ? Key[in_key] : in_key
	self
end

#in_mode(mode) ⇒ Object

Manually specifies the mode context for this tone sequence only.



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# File 'lib/jazz_model/tone_sequence.rb', line 35

def in_mode(mode)
	@mode = mode
	self
end

#in_mode_context! ⇒ Object

Shifts mode positions to place tone sequence in mode context



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# File 'lib/jazz_model/tone_sequence.rb', line 41

def in_mode_context!
	self.each {|tone| tone.position = (tone.position - mode) % self.count + 1}
	true
end

#key ⇒ Object

Takes manually specified key context for this collection or delegates to th association owner.



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# File 'lib/jazz_model/tone_sequence.rb', line 9

def key
	@key || (proxy_owner.key if proxy_owner.respond_to?(:key))
end

#mode ⇒ Object

Takes manually specified mode context for this collection or delegates to the association owner.



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# File 'lib/jazz_model/tone_sequence.rb', line 30

def mode
	@mode || (proxy_owner.mode if proxy_owner.respond_to?(:mode))
end

#notes ⇒ Object

Does the magic in determining the actual note from the tones with tone and letter indexes.



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# File 'lib/jazz_model/tone_sequence.rb', line 55

def notes
	all.map do |tone|
		Key.from_index(tone.tone, tone.letter_index).name
	end.extend(NoteSequence)
end