Class: InevitableCacophony::Rhythm

Inherits:
Object
  • Object
show all
Defined in:
lib/inevitable_cacophony/rhythm.rb

Direct Known Subclasses

Polyrhythm

Defined Under Namespace

Classes: Beat

Constant Summary collapse

START_DELAY =

Amount of silence before a note, as a fraction of the note’s duration

(0.3).rationalize
AFTER_DELAY =

Amount of silence after notes, as a fraction of duration.

(0.3).rationalize

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(beats) ⇒ Rhythm

Returns a new instance of Rhythm.



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# File 'lib/inevitable_cacophony/rhythm.rb', line 77

def initialize(beats)
	@beats = beats
end

Instance Attribute Details

#beats ⇒ Object (readonly)

Returns the value of attribute beats.



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# File 'lib/inevitable_cacophony/rhythm.rb', line 81

def beats
  @beats
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/inevitable_cacophony/rhythm.rb', line 122

def == other
	self.class == other.class &&
		self.beats == other.beats
end

#canonical ⇒ Array<Numeric,NilClass>

Returns An array where a is the amplitude of the beat at time-step i (rests are 0), or nil if no beat is played then. This will be as long as necessary to represent the rhythm accurately, including early and late beats.

Returns:

  • (Array<Numeric,NilClass>) —

    An array where a is the amplitude of the beat at time-step i (rests are 0), or nil if no beat is played then. This will be as long as necessary to represent the rhythm accurately, including early and late beats.



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# File 'lib/inevitable_cacophony/rhythm.rb', line 96

def canonical
	if duration != duration.to_i
		raise "Cannot yet canonicalise rhythms with non-integer length"
	end
        
	# Figure out the timing offset we need to allow for,
	# and space the beats enough to make it work.
	timing_offset_denominators = self.beats.map do |beat|
		beat.start_offset.rationalize.denominator
	end
	denominator = timing_offset_denominators.inject(1, &:lcm)
        
	scaled_duration = duration * denominator
	Array.new(scaled_duration).tap do |spaced_beats|
		self.beats.each_with_index do |beat, index|
			offset_index = index + beat.start_offset
			scaled_index = offset_index * denominator
			spaced_beats[scaled_index] = beat.amplitude
		end
	end
end

#duration ⇒ Integer

Returns Total duration of all beats in this rhythm.

Returns:

  • (Integer) —

    Total duration of all beats in this rhythm.



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# File 'lib/inevitable_cacophony/rhythm.rb', line 88

def duration
	each_beat.sum(&:duration)
end

#each_beat(&block) ⇒ Object 



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# File 'lib/inevitable_cacophony/rhythm.rb', line 83

def each_beat(&block)
	@beats.each(&block)
end

#inspect ⇒ Object 



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# File 'lib/inevitable_cacophony/rhythm.rb', line 118

def inspect
	"<#Rhythm duration=#{duration} @beats=#{beats.inspect}>"
end