Class: Kracker::Zooka::Pixel

Inherits:
Object
  • Object
show all
Defined in:
lib/kracker/zooka/pixel.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(color_value) ⇒ Pixel

Returns a new instance of Pixel.



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# File 'lib/kracker/zooka/pixel.rb', line 6

def initialize(color_value)
  @alpha = ChunkyPNG::Color.a(color_value)
  @red   = ChunkyPNG::Color.r(color_value)
  @green = ChunkyPNG::Color.g(color_value)
  @blue  = ChunkyPNG::Color.b(color_value)
end

Instance Attribute Details

#alpha ⇒ Object

Returns the value of attribute alpha.



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# File 'lib/kracker/zooka/pixel.rb', line 4

def alpha
  @alpha
end

#blue ⇒ Object

Returns the value of attribute blue.



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# File 'lib/kracker/zooka/pixel.rb', line 4

def blue
  @blue
end

#green ⇒ Object

Returns the value of attribute green.



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# File 'lib/kracker/zooka/pixel.rb', line 4

def green
  @green
end

#red ⇒ Object

Returns the value of attribute red.



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# File 'lib/kracker/zooka/pixel.rb', line 4

def red
  @red
end

Instance Method Details

#brightness ⇒ Object 



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# File 'lib/kracker/zooka/pixel.rb', line 13

def brightness
  0.3 * @red + 0.59 * @green + 0.11 * @blue
end

#hue ⇒ Object 



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# File 'lib/kracker/zooka/pixel.rb', line 17

def hue
  red   = @red   / 255.0
  green = @green / 255.0
  blue  = @blue  / 255.0

  min = [red, green , blue].sort.first
  max = [red, green , blue].sort.last

  h = 0
  d = 0

  if max == min
    h = 0
  else
    d = max - min
    h = case max
    when red
      (green  - blue) / d + (green  < blue ? 6 : 0)
    when green
      (blue - red) / d + 2
    when blue
      (red - green ) / d + 4
    else
      0
    end

    h = h / 6.0
  end
  h
end