Class: LuminosityContrast::Color

Inherits:
Object
  • Object
show all
Defined in:
lib/luminosity_contrast/color.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*args) ⇒ Color

Returns a new instance of Color.



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# File 'lib/luminosity_contrast/color.rb', line 5

def initialize(*args)
  input = args.size == 1 ? args[0] : args
  @r, @g, @b = Color.rgb_from(input)
end

Instance Attribute Details

#b ⇒ Object (readonly)

Returns the value of attribute b.



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# File 'lib/luminosity_contrast/color.rb', line 3

def b
  @b
end

#g ⇒ Object (readonly)

Returns the value of attribute g.



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# File 'lib/luminosity_contrast/color.rb', line 3

def g
  @g
end

#r ⇒ Object (readonly)

Returns the value of attribute r.



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# File 'lib/luminosity_contrast/color.rb', line 3

def r
  @r
end

Class Method Details

.rgb_from(input) ⇒ Object

expects a 3 or 6 character hex color code or an array with 3 numbers between 0 and 255 or an object that responds to .r, .g, .b



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# File 'lib/luminosity_contrast/color.rb', line 27

def rgb_from(input)
  case input
  when String # hex code
    raise 'Invalid hex code' unless input =~ /\A([0-9a-f]{3}){1,2}\z/i
    rgb = if input.size == 3
      input.split('').map { |h| h * 2 }
    else
      input.scan(/.{2}/)
    end
    rgb.map { |h| h.hex.to_i }
  when Array # array of numbers
    raise 'Invalid RGB array' unless input.size == 3
    input.map(&:to_f)
  when Hash
    rgb = input.values_at(:r, :g, :b)
    raise 'Invalid RGB hash' unless rgb.size == 3
    rgb.map(&:to_f)
  else
    methods = [:r,:g, :b]
    if methods.select { |m| input.respond_to?(m) }.size == methods.size
      methods.map { |m| input.send(m) }
    else
      raise 'Invalid input'
    end
  end
end

Instance Method Details

#ratio(color) ⇒ Object 



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# File 'lib/luminosity_contrast/color.rb', line 14

def ratio(color)
  LuminosityContrast.ratio(self, color)
end

#relative_luminance ⇒ Object 



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# File 'lib/luminosity_contrast/color.rb', line 10

def relative_luminance
  LuminosityContrast.relative_luminance(r,g,b)
end

#to_rgb ⇒ Object 



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# File 'lib/luminosity_contrast/color.rb', line 18

def to_rgb
  [r, g, b]
end