Class: Beats::Track

Inherits:
Object
  • Object
show all
Defined in:
lib/beats/track.rb

Overview

Domain object which models a kit sound playing a rhythm. For example, a bass drum playing every quarter note for two measures.

This object is like sheet music; the AudioEngine is responsible creating actual audio data for a Track (with the help of a Kit).

Defined Under Namespace

Classes: InvalidRhythmError

Constant Summary collapse

REST = 
"."
BEAT = 
"X"
BARLINE = 
"|"
SPACE = 
" "
DISALLOWED_CHARACTERS =

I.e., anything not an ‘X’, ‘.’, ‘|’, or ‘ ’

/[^X\.| ]/

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, rhythm) ⇒ Track

Returns a new instance of Track.



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# File 'lib/beats/track.rb', line 16

def initialize(name, rhythm)
  unless name.is_a?(String)
    raise ArgumentError, "Track name '#{name.inspect}' is invalid, must be a String"
  end

  unless rhythm.is_a?(String) && rhythm.match(DISALLOWED_CHARACTERS) == nil
    raise InvalidRhythmError, "Track '#{name}' has an invalid rhythm: '#{rhythm.inspect}'. Can only contain '#{BEAT}', '#{REST}', '#{BARLINE}', or ' '"
  end

  @name = name.dup.freeze
  @rhythm = rhythm.delete(BARLINE + SPACE).freeze

  @step_count = @rhythm.length
  @trigger_step_lengths = calculate_trigger_step_lengths.freeze
end

Instance Attribute Details

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/beats/track.rb', line 32

def name
  @name
end

#rhythm ⇒ Object (readonly)

Returns the value of attribute rhythm.



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# File 'lib/beats/track.rb', line 32

def rhythm
  @rhythm
end

#step_count ⇒ Object (readonly)

Returns the value of attribute step_count.



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# File 'lib/beats/track.rb', line 32

def step_count
  @step_count
end

#trigger_step_lengths ⇒ Object (readonly)

Returns the value of attribute trigger_step_lengths.



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# File 'lib/beats/track.rb', line 32

def trigger_step_lengths
  @trigger_step_lengths
end