HLuv is a perceptually uniform color space with a constant luminance.
Download this repository in your addons folder
$ cd ../addons/
$ git clone https://github.com/PauRosello97/ofxHLuv/
#include "ofxHLuv.h";
float hue = 30; // Hue from 0 to 360
float luminance = 60; // Luminance from 0 to 100
ofSetColor(HLuv.getColor(hue, luminance));
ofDrawRectangle(0, 0, ofGetWidth(), ofGetHeight());
Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.