// Which iteration of the Hilbert curve to draw
var iteration = 6;

// Length of each line in the Hilbert curve
var length = 5;

var forward = function(distance) {
    line(0, 0, 0, distance);
    translate(0, distance);
};

var right = function(angle) {
    rotate(angle * PI / (180+5*sin(millis())));
};

var left = function(angle) {
    right(-angle);
};

var rightHilbert;

var leftHilbert = function(l, w) {
    if (l === 0) {
        return;
    }
    right(90);
    rightHilbert(l - 1, w);
    forward(w);
    left(90);
    leftHilbert(l - 1, w);
    forward(w);
    leftHilbert(l - 1, w);
    left(90);
    forward(w);
    rightHilbert(l - 1, w);
    right(90);
};

rightHilbert = function(l, w) {
    if (l === 0) {
        return;
    }
    left(90);
    leftHilbert(l - 1, w);
    forward(w);
    right(90);
    rightHilbert(l - 1, w);
    forward(w);
    rightHilbert(l - 1, w);
    right(90);
    forward(w);
    leftHilbert(l - 1, w);
    left(90);
};

var draw = function() {
    resetMatrix();
    translate(390, 10);
    background(random(0, 200), 212, 134);
    stroke(3, 3, 3);
    strokeWeight(2);
    leftHilbert(iteration, length);
};