var radius = 150;

function setup() {
 createCanvas( 600, 600 );
 background( 255 );
 stroke( 0 );
 noFill();
 strokeWeight( 2 );
 drawCircles();
}

function draw() {}

function drawCircles() {
 background( 255 );
 for(var r = 0; r < 2; r++ ) {
 for(var c = 0; c < 2; c++ ) {
 push();
 translate( 150+(300*r), 150+(300*c));
 for(var i = 0; i < random(100,300); i++ ) {
 var a = random(0, TWO_PI);
 var x1 = radius*cos(a);
 var y1 = radius*sin(a);
 a = random(0, TWO_PI);
 var x2 = radius*cos(a);
 var y2 = radius*sin(a);
 stroke(20); 
 line( x1, y1, x2, y2);
 }
 pop();
 }
 }
}

function mousePressed() {
 drawCircles();
}