pattern

function setup() {

  createCanvas(600, 600);

  background(0);

  stroke (255,255,255);

  strokeWeight(3);

  for (var i = 0;i<100;i++){

    line(0,i*20,i*20,height);}

​

  for (var u = 0;u<100;u++){

    line(u*20,0,width,u*20);}

    stroke(255,255,255);

  strokeWeight(5);

  strokeCap(SQUARE);

  for (let y = 0; y < height; y+=10) {

    for (let x = 0; x < width; x+=10) {

      line(x, y, x+5, y+5);

    }

  }

}