keyboard.js

var keyboard = [
	["q", "w", "e", "r", "t", "y"],
	["a", "s", "d", "f", "g", "h"],
	["z", "x", "c", "v", "b", "n"]
]

var flippedX = false;
var flippedY = false;
var shifted = 0;

function flipX() {
	flippedX = flippedX ? false : true;
}
function flipY() {
	flippedY = flippedY ? false : true;
}
function shiftBy(i) {
	shifted = i;
}

function lookup(c) {
	var x = c[1];
	var y = c[0];
	if(shifted !== 0) {
		y = (Math.floor((shifted + x)/keyboard[y].length)) % keyboard.length;
		x = (shifted + x) % keyboard[y].length;
	}
	if(flippedY) {
		y = keyboard.length - 1 - y;
	}
	if(flippedX) {
		x = keyboard[y].length - 1 - x;
	} 
	
	return [y, x];

}

function read(c) {
	var ct = lookup(c);
	console.log(ct);
	console.log(keyboard[ct[0]][ct[1]]);
}

flipX()
read([0,0]);
flipY()
read([0,0]);
shiftBy(3)
read([0,0]);