converts RGB values to HSB

ruby_rgb_to_hsb.rb

# Input rgb values 1...255
# based on http://forums.devshed.com/c-programming-42/rgb-to-hsv-conversion-rountine-162526.html

r = r / 255.0
g = g / 255.0
b = b / 255.0
max = [r, g, b].max
min = [r, g, b].min
delta = max - min
v = max * 100

if (max != 0.0)
	s = delta / max *100
else
	s = 0.0
end

if (s == 0.0) 
	h = 0.0
else
	if (r == max)
		h = (g - b) / delta
	elsif (g == max)
		h = 2 + (b - r) / delta
	elsif (b == max)
		h = 4 + (r - g) / delta
	end

	h *= 60.0
	
	if (h < 0)
		h += 360.0
	end
end

# returns h in the range of 0..360 deg
# s 0...100 
# v 0...100

Nice! I'm trying to write a HSV to RGB now... :)