Find a middle color between two colors given.

midcolor.js

/**
 * From hex to dec.
 */
function hex(hex)
{
	var result = 0
	for (var i = 0; i < hex.length; i++)
	{
		result = result * 16 + '0123456789abcdefgh'.indexOf(hex[i].toLowerCase());
	}

	return result
}

/**
 * factor2 needs to be between 0 and 1, to calculate how much of the
 * two colors you want your middle color.
 */
function midcolor(color1, color2, factor2)
{
	var c1 = color1.replace('#', '').match(/.{1,2}/g)
	var c2 = color2.replace('#', '').match(/.{1,2}/g)

	var factor1 = 1 - factor2

	var c3 = [
		parseInt(hex(c1[0]) * factor1 + hex(c2[0]) * factor2).toString(16),
		parseInt(hex(c1[1]) * factor1 + hex(c2[1]) * factor2).toString(16),
		parseInt(hex(c1[2]) * factor1 + hex(c2[2]) * factor2).toString(16),
	]

	return '#' + c3.join('')
}

console.log(
	midcolor('#f0ad4e', '#5cb85c', 0.5)
)