let yoff = 0;

let zoff = 0;

let xscale_i = 0.05;

let yscale_i = 0.05;

let zscale_i = 0.0005;

let xscale = xscale_i;

let yscale = yscale_i;

let zscale = zscale_i;

let n_PIs_i = 2;

let n_PIs = n_PIs_i;

let vMag_i = 0.5;

let vMag = vMag_i;

​

let xoff_i;

let yoff_i;

let xoff_r;

let yoff_r;

let xscale_r = 0.01;

let yscale_r = 0.01;

​

let counter_x = 0;

let counter_y = 0;

let counter_speed = 0;

​

let scl = 30;

let cols, rows;

let background_a = 0.5;

let background_sub = 0;

let strokeWidthAddOn = 0;

​

let fr;

​

let controlRandom = "p";

let controlRandom_p = "p";

​

var particles = [];

let nParticlesToAdd_i = 10;

let nParticlesToAdd = 200;

let flowfield = [];

​

function setup() {

  createCanvas(windowWidth, windowHeight);

​

  //createCanvas(400, 400);

​

  cols = floor(width / scl);

  rows = floor(height / scl);

​

  pixelDensity(1);

  xoff_i = random(100);

  yoff_i = random(100);

  xoff_r = xoff_i;

  yoff_r = yoff_i;

  fr = createP("");

​

  flowfield = new Array(cols * rows);

  if (particles.length < 2500) {

    for (i = 0; i < 200; i++) {

      particles.push(new Particle());

    }

    nParticlesToAdd_i = nParticlesToAdd;

  }

​

  background(255 - background_sub);

}

​

function draw() {

  if (frameCount % 5 == 0) background(255 - background_sub, background_a);

  if (0) {

    xscale_r = random(0.005, xscale_r);

    yscale_r = random(0.005, yscale_r);

  }

​

  xoff = 0 + counter_x;

  xoff_r = xoff_i + counter_x;

​

  for (var x = 0; x < cols; x++) {

    yoff = 0 + counter_y;

    yoff_r = yoff_i + counter_y;

    for (var y = 0; y < rows + 1; y++) {

      var index = (x + y * cols) * 4;

      var index_vector = x + y * cols;

​

​

      var angle = noise(xoff, yoff, zoff) * TWO_PI * n_PIs;

      if (controlRandom === "d") {

        angle = noise(xoff, yoff, zoff) * TWO_PI * random(-n_PIs, n_PIs);

      }

      var v = p5.Vector.fromAngle(angle);

      v.setMag(vMag);

      flowfield[index_vector] = v;

​

​

      stroke(0, 50);

      strokeWeight(1);

      push();

      translate(x * scl, y * scl);

      rotate(v.heading());

      //line(0, 0, scl, 0);

      pop();

      //rect(x*scl,y*scl,scl,scl)

      yoff += yscale;

      yoff_r += yscale_r;

    }

    xoff += xscale;

    xoff_r += xscale_r;

    zoff += zscale;

  }

  // counter_x += random(counter_speed);

  // counter_y += random(counter_speed);

​

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

    particles[i].follow(flowfield, controlRandom_p);

    particles[i].update();

    particles[i].edges();

    particles[i].show(background_sub);

  }

​

  //fr.html(floor(frameRate()));

}

​

function keyTyped() {

  let controlKeys = [

    "P",

    "p",

    "C",

    "c",

    "Q",

    "q",

    "W",

    "w",

    "A",

    "a",

    "D",

    "d",

    "S",

    "s",

    "R",

    "r",

    "+",

    "=",

    "-",

    "_",

  ];

​

  if (controlKeys.includes(key)) {

    controlRandom = key;

    checkControlChanges();

  }

}

​

function checkControlChanges() {

  if (controlRandom == "p" || controlRandom == "P") {

    background(255 - background_sub, 10);

    controlRandom_p = "p";

    background_a = 5;

    xscale = xscale_i;

    yscale = yscale_i;

    zscale = zscale_i;

    vMag = vMag_i;

    n_PIs = n_PIs_i;

  }

​

  if (controlRandom == "c" || controlRandom == "C") {

    controlRandom_p = "c";

    background_a = 10;

    xscale = 0.15;

    yscale = 0.15;

    zscale = 0.009;

    vMag = 20;

    n_PIs = 6;

  }

​

  if (controlRandom == "r" || controlRandom == "R") {

    controlRandom_p = "r";

    background_a = 10;

    zscale = zscale_i;

    vMag = vMag_i;

  }

​

  if (controlRandom == "d" || controlRandom == "D") {

    background(255 - background_sub, 10);

    //controlRandom = "d";

​

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

      particles[i].updateSpeed(1);

    }

  }

​

  if (controlRandom == "a" || controlRandom == "A") {

    background(255 - background_sub, 10);

    //controlRandom = "a";

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

      particles[i].updateSpeed(-1);

    }

  }

​

  if (controlRandom == "s" || controlRandom == "S") {

    background(255 - background_sub, 10);

    controlRandom_p = "s";

    background_a = 5;

    xscale = xscale_i;

    yscale = yscale_i;

    zscale = zscale_i;

    vMag = vMag_i;

    n_PIs = 0.5;

  }

  if (controlRandom == "w" || controlRandom == "W") {

    background(255 - background_sub, 10);

    controlRandom_p = "p";

    background_a = 5;

    xscale = xscale_i;

    yscale = yscale_i;

    zscale = zscale_i;

    vMag = vMag_i;

    n_PIs = -0.5;

  }

​

  if (controlRandom === "q" || controlRandom === "Q") {

    background_sub = abs(background_sub - 255);

    background(255 - background_sub);

  }

​

  if (controlRandom == "+" || controlRandom == "=") {

    addParticles();

  }

  if (controlRandom == "-" || controlRandom == "_") {

    removeParticles();

  }

}

function addParticles() {

  if (particles.length < 2500) {

    for (i = 0; i < nParticlesToAdd_i; i++) {

      particles.push(new Particle());

    }

    nParticlesToAdd_i = nParticlesToAdd;

  }

}

​

function removeParticles() {

  particles.splice(particles.length - nParticlesToAdd_i, nParticlesToAdd_i);

  background(255 - background_sub, 10);

}

​