var lifespan = 200;

var lifeP;

var count = 0;

var target;

var maxforce = 0.4;

var rx = 100;

var ry = 150;

var rw = 200;

var rh = 10;

var currentMax;

​

function setup() {

  createCanvas(400, 300);

  population = new Population();

  lifeP = createP();

  target = createVector(width / 2, 50);

}

​

function draw() {

  background(0);

  population.run();

  lifeP.html(count);

​

  count++;

  if (count == lifespan) {

    population.evaluate();

    population.selection();

    count = 0;

  }

  fill(255);

  rect(rx, ry, rw, rh);

  ellipse(target.x, target.y, 16, 16);

}

​

function Population() {

  this.rockets = [];

  this.popsize = 25;

  this.matingpool = [];

​

  for (var i = 0; i < this.popsize; i++) {

    this.rockets[i] = new Rocket();

  }

​

  this.evaluate = function() {

    var maxfit = 0;

    for (var i = 0; i < this.popsize; i++) {

      this.rockets[i].calcFitness();

      if (this.rockets[i].fitness > maxfit) {

        maxfit = this.rockets[i].fitness;

      }

    }

    currentMax = maxfit;

    console.log(currentMax);

    for (var i = 0; i < this.popsize; i++) {

      this.rockets[i].fitness /= maxfit;

    }

​

    this.matingpool = [];

    for (var i = 0; i < this.popsize; i++) {

      var n = this.rockets[i].fitness * 100;

      for (var j = 0; j < n; j++) {

        this.matingpool.push(this.rockets[i]);

      }

    }

  }

​

  this.selection = function() {

    var newRockets = [];

    for (var i = 0; i < this.rockets.length; i++) {

      var parentA = random(this.matingpool).dna;

      var parentB = random(this.matingpool).dna;

      var child = parentA.crossover(parentB);

      child.mutation();

      newRockets[i] = new Rocket(child);

    }

    this.rockets = newRockets;

  }

  this.run = function() {

    for (var i = 0; i < this.popsize; i++) {

      this.rockets[i].update();

      this.rockets[i].show();

    }

  }

}

​

function DNA(genes) {

  if (genes) {

    this.genes = genes;

  } else {

    this.genes = [];

    for (var i = 0; i < lifespan; i++) {

      this.genes[i] = p5.Vector.random2D();

      this.genes[i].setMag(maxforce);

    }

  }

  this.crossover = function(partner) {

    var newgenes = [];

    var mid = floor(random(this.genes.length));

    for (var i = 0; i < this.genes.length; i++) {

      if (i > mid) {

        newgenes[i] = this.genes[i];

      } else {

        newgenes[i] = partner.genes[i];

      }

    }

    return new DNA(newgenes);

  }

​

  this.mutation = function() {

    for (var i = 0; i < this.genes.length; i++) {

      if (random(1) < 0.01) {

        this.genes[i] = p5.Vector.random2D();

        this.genes[i].setMag(maxforce);

      }

    }

  }

​

}

​

function Rocket(dna) {

  this.pos = createVector(width / 2, height);

  this.vel = createVector();

  this.acc = createVector();

  this.completed = false;

  this.crashed = false;

  if (dna) {

    this.dna = dna;

  } else {

    this.dna = new DNA();

  }

  this.fitness = 0;

​

  this.applyForce = function(force) {

    this.acc.add(force);

  }

​

  this.calcFitness = function() {

    var d = dist(this.pos.x, this.pos.y, target.x, target.y);

    this.fitness = map(d, 0, width, width, 0);

​

    if (this.completed) {

      this.fitness *= 10;

    }

​

    if (this.crashed) {

      this.fitness /= 10;

    }

​

  }

​

  this.update = function() {

    var d = dist(this.pos.x, this.pos.y, target.x, target.y);

    if (d < 10) {

      this.completed = true;

      this.pos = target.copy();

      console.log("Target Reached");

    }

​

    if (this.pos.x > rx && this.pos.x < rx + rw && this.pos.y > ry && this.pos.y < ry + rh) {

      this.crashed = true;

    }

​

    if (this.pos.x > width || this.pos.x < 0) {

      this.crashed = true;

    }

​

    if (this.pos.y > height || this.pos.y < 0) {

      this.crashed = true;

    }

​

    this.applyForce(this.dna.genes[count]);

    if (!this.completed && !this.crashed) {

      this.vel.add(this.acc);

      this.pos.add(this.vel);

      this.acc.mult(0);

      this.vel.limit(4);

    }

  }

​

  this.show = function() {

    push();

    noStroke();

    fill(255, 150);

    translate(this.pos.x, this.pos.y);

    rotate(this.vel.heading());

    rectMode(CENTER);

    rect(0, 0, 25, 5);

    pop();

  }

}