Colourful fibonacci spiral.

Tushar

var a = 1;
var b = 1;
var mode = 0;
var recta = 0;
var rectb = 0;
var xpos = 0;
var ypos = 0;
var rgb;

function setup(){
    createCanvas(1600,900);
    background(0);
    noFill();
    strokeWeight(1);
    rectMode(CORNERS);
}

function draw(){

    if (a > 2*width && a > 2*height){
        noLoop();
    }

    if (mode == 0){
        xpos -= ((b-a) / 2);
    }

    else if (mode == 1){
        ypos -= (b-a) / 2;
    }

    else if (mode == 2){
        xpos += (b-a) / 2;
    }

    else {
        ypos += (b-a) / 2;
    }

    rgb = getRGB();
    stroke(rgb[0], rgb[1], rgb[2]);

    translate(width / 2 + xpos, height / 2 + ypos);
    arc( 0 , 0 , b, b, mode* (PI / 2), (mode * PI / 2) + PI/2, PIE);

    temp = a;
    a = b;
    b = b + temp;

    mode+=1;
    mode%=4;
}

function getRGB(){
    var end = 0;
    while (end == 0){
        var r = random([0,127,255]);
        var g = random([0,127,255]);
        var b = random([0,127,255]);

        if (r+g+b > 0){end = 1;} 
    }
    return [r,g,b];
}