<iframe width='500px' height='400px' src='https://nest.ktbyte.com/nest#358301' allowfullscreen></iframe>

int n=20;       // any values here ~30 and over will take too long to run and be seen as infinite loop
int[] fib = new int[n];

int RIGHT = 0;
int UP = 1;
int LEFT = 2;
int DOWN = 3;

// initialized for every spiral
int direction, b;
float x, y;

PImage bg = loadImage("https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTSCZec0R3WXp0ksCLw8ykZKzcNSILxa9hq6p_czrE88xtxl3EncRXv6Orqgx1K-WVN0aQ&usqp=CAU");

void setup() {
    size(1000, 1000);
    colorMode(HSB);
    strokeWeight(3);
    
    // fill the array with fibonacci numbers
    fib[0] = 1;
    fib[1] = 1;
    for(int i=2; i<n; i++) {
        fib[i] = fib[i-1] + fib[i-2]; 
    }
}


void draw() {

    background(255);
    image(bg, 0, 0, width, height);
    
    drawSpiral();
        
    // show the ratio on the screen
    fill(0);
    float ratio = (float)fib[n-1] / fib[n-2];
    textSize(40);
    text("Golden Ratio: " + nf(ratio, 0, 6), 100, 150);
}

void drawSpiral() {
    x = width/2;
    y = width/2;
    
    // uncomment this line to draw a static image (no motion)
    // direction = 2;
    b = 0;
    
    stroke(255);
    
    // draw the spiral
    for(int i=0; i<n; i++) {
        fill(128, 200, b, 50);
        stroke(0);
        rect(x, y, fib[i], fib[i]);
        
        
        drawArc(i, direction);
        
        
        // change start point for next rectangle
        if(i > 0) {
            if(direction == RIGHT) {
                x = x + fib[i];
            } else if(direction == UP) {
                x = x - fib[i-1];
                y = y + fib[i];
            } else if(direction == LEFT) {
                x = x - fib[i] - fib[i-1];
                y = y - fib[i-1];
            } else {
                y = y - fib[i] - fib[i-1];
            }
            
            direction = (direction + 1) % 4;
        }
        b += 15; b %= 256;
    }
}

void drawArc(int i, int direction) {
    if(direction == 0) {
        arc(x + fib[i], y + fib[i], fib[i]*2, fib[i]*2, PI, TWO_PI-PI/2);
    } else if(direction == 1) {
        arc(x, y + fib[i], fib[i]*2, fib[i]*2, TWO_PI-PI/2, TWO_PI);
    } else if(direction == 2) {
        arc(x, y, fib[i]*2, fib[i]*2, 0, PI/2);
    } else {
        arc(x + fib[i], y, fib[i]*2, fib[i]*2, PI/2, PI);
    }
}