class RubyXL::ColorConvenienceClasses::RgbColor

ciintelligence.blogspot.com/2012/02/converting-excel-theme-color-and-tint.html

Attributes

a[RW]
b[RW]
g[RW]
r[RW]

Public Class Methods

parse(str) click to toggle source
# File lib/rubyXL/convenience_methods/color.rb, line 62
def self.parse(str)
  r, g, b, a = str.unpack("A2A2A2A2")

  rgb_color = RgbColor.new
  rgb_color.r = r && r.to_i(16)
  rgb_color.g = g && g.to_i(16)
  rgb_color.b = b && b.to_i(16)
  rgb_color.a = a && a.to_i(16)

  rgb_color
end

Public Instance Methods

to_hls() click to toggle source
# File lib/rubyXL/convenience_methods/color.rb, line 24
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
to_s() click to toggle source
# File lib/rubyXL/convenience_methods/color.rb, line 74
def to_s
  str = r.to_s(16) + g.to_s(16) + b.to_s(16)
  str += a.to_s(16) if a && a != 0
  str
end