Class: PhotoUtils::Compensation

Inherits:
Value show all
Defined in:
lib/photo_utils/compensation.rb

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Value

#<=>, #==, #decr, #incr, #initialize

Methods inherited from Float

#format, #prec

Constructor Details

This class inherits a constructor from PhotoUtils::Value

Class Method Details

.new_from_factor(f) ⇒ Object

amount specified in factor



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# File 'lib/photo_utils/compensation.rb', line 7

def self.new_from_factor(f)
  new(f)
end

.new_from_v(v) ⇒ Object 



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# File 'lib/photo_utils/compensation.rb', line 11

def self.new_from_v(v)
  new(2 ** v)
end

Instance Method Details

#format_factor ⇒ Object 



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# File 'lib/photo_utils/compensation.rb', line 23

def format_factor
  "x%.1f" % to_f.format(10)
end

#format_value ⇒ Object 



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# File 'lib/photo_utils/compensation.rb', line 27

def format_value
  v = to_v
  "Cv:%s%s" % [
    (v < 0) ? '-' : '+',
    v.abs.format(10)
  ]
end

#to_factor ⇒ Object 



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# File 'lib/photo_utils/compensation.rb', line 15

def to_factor
  to_f
end

#to_s(format = :factor) ⇒ Object 



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# File 'lib/photo_utils/compensation.rb', line 35

def to_s(format=:factor)
  case format
  when :factor
    format_factor
  when :value
    format_value
  else
    raise "Unknown format: #{format.inspect}"
  end
end

#to_v ⇒ Object 



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# File 'lib/photo_utils/compensation.rb', line 19

def to_v
  Math.log2(to_f)
end