// lynntf January 2020

​

max_iters = 2000;

startup = 5;

xmin = 0;

xmax = 0;

ymin = 0;

ymax = 0;

maxnum = 100;

maxexposures = 10000000;

num = 0;

exposures = 0;

min_dim = 500;

dimx = 500;

dimy = 500;

shift_x = 0;

shift_y = 0;

m = 0;

q = 0;

K = 0.971635;

A = 1.0;

B = 1.0/A;

C = 1.0/A;

let slider;

// let inp;

​

let travelers = [];

​

function setup() {

  slider = createSlider(0,2,0.8,0.000001);

  slider.position(10,10);

  slider.style('width', '100px');

  slider.input(sliderFunction);

  inp = createInput(K);

  inp.position(120, 10);

  inp.size(100);

  inp.input(inputFunction);

  // slider.style('width', '100px')

  ymax = 2*PI;

  xmax = 2*PI;

  shift_x = PI;

  // shift_x = 0;

  shift_y = 0;

  var canvas = createCanvas(500, 500);

  // canvas.parent('p5sketch');

  background(0,0,0);

  colorMode(HSB);

  for (i = 0; i < maxnum; i++) {

    travelers[i] = new traveler(i);

    num++;

  }

}

​

function inputFunction(){

  slider.value(inp.value());

}

function sliderFunction(){

  inp.value(slider.value());

}

​

function draw() {

  if (exposures < maxexposures) {

    for (i = 0; i < maxnum; i++) {

      travelers[i].draw();

    }

    exposures += num;

  }

  q++;

  if (q > 15) {

    q = 0;

    m = 0;

  }

}

​

function touchStarted() {

  m++;

  q = 0;

  if (m > 1) {

    exposures = 0;

    background(0);

    for (i = 0; i < maxnum; i++) {

      travelers[i].rebirth();

    }

    m = 0;

    if (K == slider.value()){

      K = 4*random();

      slider.value(K);

    } else {

      K = slider.value();

    }

    console.log("K = ",K);

    inp.value(K); 

  }

}

​

​

class traveler {

  constructor(i) {

    this.x = random()*(xmax - xmin) + xmin;

    this.xo = this.x;

    this.y = random()*(ymax - ymin) + ymin;

    this.yo = this.y;

    this.xn = 0;

    this.yn = 0;

    this.xp = 0;

    this.yp = 0;

    this.age = 0;

    this.hue = random();

  }

​

  draw() {

    this.xn = (A*this.x + K*sin(this.y) + 2*PI)%(2*PI);

    this.yn = (B*this.y + C*this.xn + 2*PI)%(2*PI);

    this.x = this.xn;

    this.y = this.yn;

    if (i > startup) {

      this.xp = (this.x - shift_x + 2*PI)%(2*PI);

      this.yp = (this.y - shift_y + 2*PI)%(2*PI);

      // this.xp = (this.x + K*sin(this.y)/2 - shift_x + 2*PI)%(2*PI);

      // this.yp = (this.y + this.x - shift_y + 2*PI)%(2*PI);

      this.xp = (this.xp - xmin) / (xmax - xmin) * dimx;

      this.yp = (this.yp - ymin) / (ymax - ymin) * dimy;

      // stroke(this.xo*255/(2*PI), this.yo*255/(2*PI), 255, 0.1);

      stroke(this.hue*255, 255, 255, 0.2);

      point(this.yp, this.xp);

    }

    this.age++;

    if (this.age > max_iters) {

      this.rebirth();

    }

  }

​

  rebirth() {

    this.x = random()*(xmax - xmin) + xmin;

    this.xo = this.x;

    this.y = random()*(ymax - ymin) + ymin;

    this.yo = this.y;

    this.age = 0;

    this.hue = random();

  }

}