let lineSpacing;

let linePoints = [];

​

function setup() {

  createCanvas(800, 800);

  lineSpacing = width / numLines;

  for (let i = 0; i < numLines; i++) {

    let points = [];

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

      points.push(createVector(i * lineSpacing + random(-5, 5), y));

    }

    linePoints.push(points);

  }

}

​

function draw() {

  background(255);

  stroke(0);

  for (let i = 0; i < numLines; i++) {

    let points = linePoints[i];

    for (let j = 0; j < points.length - 1; j++) {

      line(points[j].x, points[j].y, points[j + 1].x, points[j + 1].y);

    }

  }

}

​