How do I determine darker or lighter color variant of a given color?

Question

Given a source color of any hue by the system or user, I\'d like a simple algorithm I can use to work out a lighter or darker variants of the selected color. Similar to effe

Answer 1

Assuming you get the color as RGB, first convert it to HSV (hue, saturation, value) color space. Then increase/decrease the value to produce lighter/darker shade of the color. Then convert back to RGB.