* Laura Tessin

 * prompt: lush green

 *

 * based on: https://editor.p5js.org/ada10086/sketches/r1gmVaE07

 *

 */

​

var num = 1800;         // number of particles 

var noiseScale = 500;   // higher number -> being pulled in similar direction

var noiseStrength = -0.5;  // change direction

var particles = [num];

var direction = 1;

let canvas_size;

var noise_slider;

var speed_slider;

const colors = ['#B7CF0C',

                '#92C43C',

                '#85B72F',

                '#CDDD55',

                '#86BD26',

                '#B2C718',

                '#939730',

                '#809108',

                '#84A54A',

                '#F9CA00']

​

function setup() {

​

  // set up canvas

  canvas_size = windowHeight;

  createCanvas(canvas_size, canvas_size);

​

  noStroke();

  // set up slider

  noise_slider = createSlider(5, 500 ,500);

  noise_slider.position(10, canvas_size - 30);

  speed_slider = createSlider(0.5, 1.5, 1, 0.5);

  speed_slider.position(160, canvas_size - 30);

​

  // create particles

  for (let i = 0; i < num; i++) {

    var loc = createVector(random(-20, canvas_size + 20), random(-20, canvas_size + 20), 5);

    var angle = 0;

    var dir = createVector(cos(angle), sin(angle));

    var speed = random(0.5,2);

    var particle_col = random(colors);

    particles[i] = new Particle(loc, dir, speed, particle_col);

  }

}

​

function draw() {

​

  // draw background

  fill(54, 76, 15, 10)

  noStroke();

  rect(0, 0, width, height);

​

  // update slider values

  const n = noise_slider.value();

  noiseScale = n;

  const s = speed_slider.value();

  direction = s;

  // update particles

  for (let i = 0; i < particles.length; i++) {

    particles[i].run();

  }

}

​

class Particle{

​

  constructor(_loc,_dir,_speed, _color){

    this.loc = _loc;

    this.dir = _dir;

    this.speed = _speed;

    this.color = _color;

  }

​

  run() {

    this.move();

    this.checkEdges();

    this.update();

  }

​

  move() {

    let angle = noise(this.loc.x/noiseScale, this.loc.y/noiseScale, frameCount/noiseScale) * TWO_PI * noiseStrength;

    this.dir.x = cos(angle);

    this.dir.y = sin(angle);

    var vel = this.dir.copy();

    var d = direction;  //direction change

    vel.mult(this.speed * d);

    this.loc.add(vel);

  }

​

  checkEdges() {

    if (this.loc.x<0 || this.loc.x > canvas_size || this.loc.y < 0 || this.loc.y > canvas_size) {    

      this.loc.x = random(-20, canvas_size + 20);

      this.loc.y = random(-50, canvas_size);

    }

  }

​

  update() {

    fill(this.color);

    ellipse(this.loc.x, this.loc.y, this.loc.z, 5);

  }

}