font-color.js

/**
 * @url http://stackoverflow.com/questions/1855884/determine-font-color-based-on-background-color
 * @url http://stackoverflow.com/questions/596216/formula-to-determine-brightness-of-rgb-color
 **/
function perceptiveLuminance(color) {
    return 1 - (0.299 * color.r + 0.587 * color.g + 0.114 * color.b) / 255
}

function getFontColor(backgroundColor) {
    if (perceptiveLuminance(backgroundColor) < 0.5) {
        return {
            r: 0,
            g: 0,
            b: 0
        }
    } else {
        return {
            r: 255,
            g: 255,
            b: 255
        }
    }
}