Vivid line

let num = 20;

let vecLocation = [];

let vecVelocity = [];

let fillRed = [];

let fillGreen = [];

let fillBlue = [];

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  frameRate(60);

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

    vecLocation[i] = createVector(width / 2, height / 2);

    vecVelocity[i] = createVector(random(-2, 2), random(-2, 2));

    fillRed[i] = Math.floor(Math.random()*2)*255

    fillGreen[i]= Math.floor(Math.random()*2)*255

    fillBlue[i]= Math.floor(Math.random()*2)*255

  }

   background(0);

}

​

function draw() {

 // background(0);

  noStroke();

  let diamiter= 20;

​

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

    fill(fillRed[i],fillGreen[i],fillBlue[i])

    vecLocation[i].add(vecVelocity[i]);

      ellipse(vecLocation[i].x, vecLocation[i].y, diamiter+i*2,diamiter+i*2);

    if (vecLocation[i].x < 0 || vecLocation[i].x > width ) {

      vecVelocity[i].x = vecVelocity[i].x * -1;

      fillRed[i] = Math.floor(Math.random()*2)*255

      fillGreen[i] = Math.floor(Math.random()*2)*255

      fillBlue[i] = Math.floor(Math.random()*2)*255

    }

    if (vecLocation[i].y < 0 || vecLocation[i].y > height) {

      vecVelocity[i].y = vecVelocity[i].y * -1;

      fillRed[i] = Math.floor(Math.random()*2)*255

      fillGreen[i] = Math.floor(Math.random()*2)*255

      fillBlue[i] = Math.floor(Math.random()*2)*255

    }

  }

}