beginning additive color theory

gistfile1.rb

# this gist teaches you how to balance colors using HEX-to-DEC conversions.
# In color theory, additive colors are colors that, when combined, produce solid white.

# HEX primaries, plus black and white

# remember, HEX colors desribe the state of a color channel. think of 00 as "OFF" and FF as "ON".
@red   = "FF0000" # red channel fully ON, all else fully OFF
@green = "00FF00" # green channel fully ON, all else fully OFF
@blue  = "0000FF" # blue channel fully ON, all else fully OFF
@black = "000000" # all channels fully OFF
@white = "FFFFFF" # all channels fully ON

# in other words, the shade white is produced when all the channels are ON, and the shade black is produced when all the channels are OFF.
# all other colors are produced by mixing the primary channels - red, green, and blue.

# Let's start converting the primary HEX colors to DEC.

class String
  def to_dec
    @colors = []
    self.scan(/.{2}/).each do |component|
      @colors << component.to_i(16)
    end
    return @colors
  end
end

puts @red.to_dec

# now we can start doing some math

red_in_dec = @red.to_dec
blue_in_dec = @blue.to_dec

combo = red_in_dec + blue_in_dec
puts combo.to_s


# yet there's a slight problem... we haven't actually added the values in each channel
# try an easy loop
i = 0
new_color = []
while i<3 do
  new_color << @red.to_dec[i] + @blue.to_dec[i]
  i += 1
end
puts new_color.to_s

# let's make a method out of that!

def add_two_colors(color1,color2)
  i = 0
  new_color = []
  while i<3 do
    new_color << @red.to_dec[i] + @blue.to_dec[i]
    i += 1
  end
  return new_color
end

puts add_two_colors(@red,@blue).to_s

# soon, we'll be adding as many colors as we want
# (consider: how much is too much when combining colors?)