var rgb = function(r, g, b, a) { var a = a || 255; return ~~ a << 32 ^ ~~ r << 16 ^ ~~ g << 8 ^ ~~ b; } var hsv = function(h, s, v) { } var red = function(color) { } var var hex = function(color) { return '#'+color.toString(16); } console.log(hex(rgb(0, 0, 255, 255)));