wordColors.js

var actualCharacterIndex = -1;
var alphabet = 'abcdefghijklmnopqrstuvwxyz!?1234567890 ';
var word = window.prompt('Please a word or sentence you think is funny',
	'badibaduba');

function setup() {
	colorMode(HSB, alphabet.length, word.length, 1, 1);
	createCanvas(windowWidth, windowHeight);
}

function draw() {
	var endOfWordReached = word.length - 1 === actualCharacterIndex;
	actualCharacterIndex = !endOfWordReached ? actualCharacterIndex + 1 : -1;
	var character = getCharacterByIndex(word, actualCharacterIndex);
	colorize(character);
}

function getCharacterByIndex(string, index) {
	return string.split('')[index];
}

function colorize(character) {
	var positionInAlphabet = alphabet.indexOf(character);
	background(positionInAlphabet, actualCharacterIndex, 1, 1);
}