Let's say I've got the colour FF0000, which is red. Finding a darker colour is easy, I just type maybe CC instead of the FF, but let's say I've got the colour AE83FC, which is a complicated colour, how the heck would I find a lighter or darker version of it automatically?

I figured the easy way to do this is to convert my RGB to HSB [Hue, Saturation, Brightness]

How would I do that in Objective-C?

Let's say I've got a RGB which is: 1.0, 0.0, 0.0. That's red.

CGFloat r = 1.0;
CGFloat g = 0.0;
CGfloat b = 0.0;

How would I convert that to HSB and then transform the colors and make it go back to RGB to I can use CGContextRGBSetFillColor?

Are there any HSB functions?

Please help. :)