Class: Musicality::Meter

Inherits:
Object
  • Object
show all
Includes:
Parseable, Packable, Validatable
Defined in:
lib/musicality/notation/model/meter.rb,
lib/musicality/printing/lilypond/meter_engraving.rb,
lib/musicality/notation/parsing/convenience_methods.rb

Constant Summary collapse

PARSER = 
Parsing::MeterParser.new
CONVERSION_METHOD = 
:to_meter

Constants included from Parseable

Parseable::DEFAULT_SPLIT_PATTERN

Constants included from Packable

Packable::PACKED_CLASS_KEY

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Parseable

included

Methods included from Validatable

#errors, #invalid?, #valid?, #validatables, #validate

Methods included from Packable

#class_str, included, #init_params, #pack, pack_val, recover_class, unpack_val

Constructor Details

#initialize(beats_per_measure, beat_duration) ⇒ Meter

Returns a new instance of Meter.



12
13
14
15
16
 
# File 'lib/musicality/notation/model/meter.rb', line 12

def initialize beats_per_measure, beat_duration
  @beats_per_measure = beats_per_measure
  @beat_duration = beat_duration
  @measure_duration = beats_per_measure * beat_duration    
end

Instance Attribute Details

#beat_duration ⇒ Object (readonly)

Returns the value of attribute beat_duration.



10
11
12
 
# File 'lib/musicality/notation/model/meter.rb', line 10

def beat_duration
  @beat_duration
end

#beats_per_measure ⇒ Object (readonly)

Returns the value of attribute beats_per_measure.



10
11
12
 
# File 'lib/musicality/notation/model/meter.rb', line 10

def beats_per_measure
  @beats_per_measure
end

#measure_duration ⇒ Object (readonly)

Returns the value of attribute measure_duration.



10
11
12
 
# File 'lib/musicality/notation/model/meter.rb', line 10

def measure_duration
  @measure_duration
end

Instance Method Details

#==(other) ⇒ Object 



42
43
44
45
 
# File 'lib/musicality/notation/model/meter.rb', line 42

def ==(other)
  return (@beats_per_measure == other.beats_per_measure &&
    @beat_duration == other.beat_duration)
end

#check_beat_duration ⇒ Object 



32
33
34
35
36
37
38
39
40
 
# File 'lib/musicality/notation/model/meter.rb', line 32

def check_beat_duration
  unless @beat_duration > 0
    raise NonPositiveError, "beat duration #{@beat_duration} is not positive"
  end
  
  unless @beat_duration > 0
    raise NonRationalError, "beat duration #{@beat_duration} is a rational"
  end
end

#check_beats_per_measure ⇒ Object 



22
23
24
25
26
27
28
29
30
 
# File 'lib/musicality/notation/model/meter.rb', line 22

def check_beats_per_measure
  unless @beats_per_measure > 0
    raise NonPositiveError, "beats per measure #{@beats_per_measure} is not positive"
  end
  
  unless @beats_per_measure.is_a?(Integer)
    raise NonIntegerError, "beats per measure #{@beats_per_measure} is not an integer"
  end
end

#check_methods ⇒ Object 



18
19
20
 
# File 'lib/musicality/notation/model/meter.rb', line 18

def check_methods
  [ :check_beats_per_measure, :check_beat_duration ]
end

#to_lilypond ⇒ Object 



4
5
6
7
8
 
# File 'lib/musicality/printing/lilypond/meter_engraving.rb', line 4

def to_lilypond
  num = beats_per_measure * beat_duration.numerator
  den = beat_duration.denominator
  "\\time #{num}/#{den}"
end

#to_s ⇒ Object 



47
48
49
50
51
52
53
54
55
 
# File 'lib/musicality/notation/model/meter.rb', line 47

def to_s
  if beat_duration.numerator == 1
    num = beats_per_measure * beat_duration.numerator
    den = beat_duration.denominator
    "#{num}/#{den}"
  else
    "#{beats_per_measure}*#{beat_duration}"
  end
end