Method: RubyXL::ColorConvenienceClasses::RgbColor#to_hls

Defined in:
lib/rubyXL/convenience_methods/color.rb

#to_hls ⇒ Object

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# File 'lib/rubyXL/convenience_methods/color.rb', line 22

def to_hls
  hls_color = HlsColor.new

  # Note that we are overriding accessors with local vars here:
  r = self.r / 255.0
  g = self.g / 255.0
  b = self.b / 255.0

  hls_color.a = (self.a || 0) / 255.0

  min = [r, g, b].min
  max = [r, g, b].max
  delta = max - min

  if (max == min) then
    hls_color.h = hls_color.s = 0
    hls_color.l = max
    return hls_color
  end

  hls_color.l = (min + max) / 2

  if (hls_color.l < 0.5) then
    hls_color.s = delta / (max + min);
  else
    hls_color.s = delta / (2.0 - max - min);
  end

  hls_color.h = (g - b) / delta       if (r == max)
  hls_color.h = 2.0 + ((b - r) / delta) if (g == max)
  hls_color.h = 4.0 + ((r - g) / delta) if (b == max)

  hls_color.h *= 60;
  hls_color.h += 360 if hls_color.h < 0

  hls_color
end