​

let myp = 50;                 // starting points / lines

let iterations = 300;         // line segments

let tn;                       // angle

let u = 0.918;                // ikeda factor

​

var xn = [iterations];

var yn = [iterations];

​

function setup() {

  createCanvas(500, 500);

  noLoop();

}

​

function draw() {

  background(255);

  translate(width / 2, height / 2);

  for (let i = 0; i < myp; i++) ikeda();

}

​

function ikeda() {

  xn[0] = random(-1, 1) * width / 2; // related to center translate need all 4 quadrants

  yn[0] = random(-1, 1) * height / 2;

  strokeWeight( random(1,4) );

  stroke( random(100,200),random(100,200),random(100,200) );

  for (let i = 1; i < iterations; i++) {

    tn = 0.4 - (6 / (1 + pow(xn[i - 1], 2) + pow(yn[i - 1], 2)));

    xn[i] = 1 + u * (xn[i - 1] * cos(tn) - yn[i - 1] * sin(tn));

    yn[i] = u * (xn[i - 1] * sin(tn) + yn[i - 1] * cos(tn));

    line(xn[i - 1], yn[i - 1], xn[i], yn[i]);

  }

}

​

/*

// IKEDA Function

// https://discourse.processing.org/t/drawing-ikeda-function/9536

// https://en.wikipedia.org/wiki/Ikeda_map#Octave/MATLAB_code_for_point_trajectories

​

int p =100;                  // starting points / lines

int iterations = 1000;       // line segments

float tn;                    // angle

float u = 0.9;//0.918;             // ikeda factor

float[] xn = new float[iterations];

float[] yn = new float[iterations];

color cp;

​

void setup() {

  size(500, 500);

  noLoop();

}

​

void ikeda() {

  xn[0] = random(-1,1)*width/2;  // related to center translate need all 4 quadrants

  yn[0] = random(-1,1)*height/2; 

  cp = color(random(127,200),random(127,200),random(127,200));

  for (int i=1; i<iterations; i++) {

    tn  = 0.4 - (6 /(1+pow(xn[i-1], 2) + pow(yn[i-1], 2)));

    xn[i] = 1 + u * (xn[i-1]* cos(tn) - yn[i-1]*sin(tn));

    yn[i] = u*( xn[i-1]*sin(tn)+yn[i-1]*cos(tn));

    stroke(cp);

    line(xn[i-1], yn[i-1], xn[i], yn[i]);

  }

}

​

void draw() {

  background(200,200,0);

  translate(width/2, height/2);

  for ( int k=0; k<p; k++) ikeda();

}

​

void mouseWheel(MouseEvent event) {

  float e = event.getCount();

  u += e*0.02;

  println("ikead: "+nf(u,1,3));

  redraw();

}

​

*/