function fnGetRandomColour(iDarkLuma, iLightLuma)
{
for (var i=0;i<20;i++)
{
var sColour = ('ffffff' + Math.floor(Math.random() * 0xFFFFFF).toString(16)).substr(-6);
var rgb = parseInt(sColour, 16); // convert rrggbb to decimal
var r = (rgb >> 16) & 0xff; // extract red
var g = (rgb >> 8) & 0xff; // extract green
var b = (rgb >> 0) & 0xff; // extract blue
var iLuma = 0.2126 * r + 0.7152 * g + 0.0722 * b; // per ITU-R BT.709
if (iLuma > iDarkLuma && iLuma < iLightLuma) return sColour;
}
return sColour;
}
For pastel, pass in higher luma dark/light integers - ie fnGetRandomColour(120, 250)
Credits: all credits to http://paulirish.com/2009/random-hex-color-code-snippets/ stackoverflow.com/questions/12043187/how-to-check-if-hex-color-is-too-black