Genetic Alogorithm

Class for Rocket Object

// Constructor function
function Rocket(dna) {
  this.locations=[];
  var rightWall;
  var leftWall;
  // Physics of rocket at current instance
  this.pos = createVector(0, height/2);
  this.vel = createVector();
  this.acc = createVector();
  // Checkes rocket has reached target
  this.completed = false;
  // Checks if rocket had crashed
  this.crashed = false;
  this.hitWall=false;
  // Gives a rocket dna
  if (dna) {
    this.dna = dna;
  } else {
    this.dna = new DNA();
  }
  this.fitness = 0;

// Object can recieve force and add to acceleration
  this.applyForce = function(force) {
    this.acc.add(force);
  }
  // Calulates fitness of rocket
  this.calcFitness = function() {
    // Takes distance to target
    var d = dist(this.pos.x, this.pos.y, target.x, target.y);

// Maps range of fitness
    this.fitness = map(d, 0, width, width, 0);
	this.fitness=pow(this.fitness,2);
    // If rocket gets to target increase fitness of rocket
    if (this.completed) {
      this.fitness = pow(this.fitness,2);
    }
    // If rocket does not get to target decrease fitness
    if (this.crashed) {
      this.fitness /= 100;
    }
	if(leftWall){this.fitness/=100};
	if(rightWall){this.fitness*=100;}

}
  // Updates state of rocket
  this.update = function(array) {
	rightWall=false;
	leftWall=false;
    // Checks distance from rocket to target
    var d = dist(this.pos.x, this.pos.y, target.x, target.y);
    // If distance less than 10 pixels, then it has reached target
    if (d < 10) {
      this.completed = true;
      this.pos = target.copy();
    }
    // Rocket hit the wall
   
	for(var i=0; i< array.length;i++){
		if (this.pos.x>array[i].x && this.pos.x< array[i].x+10 && this.pos.y>array[i].y && this.pos.y < array[i].y+120){
			this.crashed=true;
			this.hitWall=true;
			break;
		}
	}
    // Rocket has hit left  of window
    if (this.pos.x < 0) {
      this.crashed = true;
	  leftWall=true;
    }
	//hit the right wall(bonus of fitness)
	if(this.pos.x>width){
	  rightWall=true;
	}
    // Rocket has hit top or bottom of window
    if (this.pos.y > height || this.pos.y < 0) {
      this.crashed = true;
    }
	
	
    //applies the random vectors defined in dna to consecutive frames of rocket
    this.applyForce(this.dna.genes[count]);
    // if rocket has not got to goal and not crashed then update physics engine
    if (!this.completed && !this.crashed) {
	  if(drawBoo){
	  this.locations.push({x:this.pos.x,y:this.pos.y});}
      this.vel.add(this.acc);
      this.pos.add(this.vel);
      this.acc.mult(0);
      this.vel.limit(4);
	 
	  
	  fill(100,150,100);
	}
  }
  // displays rocket to window
  this.show = function() {
    // push and pop allow's rotating and translation not to affect other objects
    push();
    //color customization of rockets
    noStroke();
    fill(255, 150);
    //translate to the postion of rocket
    translate(this.pos.x, this.pos.y);
    //rotatates to the angle the rocket is pointing
    rotate(this.vel.heading());
    //creates a rectangle shape for rocket
    rectMode(CENTER);
    rect(0, 0, 25, 5);
    pop();
	if(this.locations==lifespan){this.locations=[];}
	if(this.locations.length>2){
		for(var i=0; i<this.locations.length-1;i++){
			stroke(150,150,150);
			line(this.locations[i].x,this.locations[i].y,this.locations[i+1].x,this.locations[i+1].y);
		}
	}
  }

}

Class for DNA Object

// Adds random mutation to the genes to add variance.
  this.mutation = function(num) {
    for (var i = 0; i < this.genes.length; i++) {
      // if random number less than 0.01, new gene is then random vector
	    if(num>0.6){
			if (random(1) < 0.3){
			this.genes[i] = p5.Vector.random2D();
			this.genes[i].setMag(maxforce);
			}
		}
		else if (random(1) < 0.02) {
				this.genes[i] = p5.Vector.random2D();
				this.genes[i].setMag(maxforce);
		}
	  }
    }
  }

Class for Population Object

function Population() {
  // Array of rockets
  this.rockets = [];
  this.average;
  var solution=false;
  var path;
  var total=0;
  // Amount of rockets
   // this.popsize = 10;
  // Amount parent rocket partners
  //this.matingpool = [];

// Associates a rocket to an array index
  for (var i = 0; i < popSize; i++) {
    this.rockets[i] = new Rocket();
  }

this.evaluate = function() {
	average=0;
	total=0;
	solution=false;
	for(var i=0;i<this.rockets.length;i++){
		if(this.rockets[i].completed){
			solution=true;
			path=this.rockets[i].dna;
		}
	}
	if(solution){
		for(var i=0; i<this.rockets.length;i++){
			this.rockets[i]=new Rocket(path);
		}
	}
	else{
    var maxfit = 0;
    // Iterate through all rockets and calcultes their fitness
    for (var i = 0; i < popSize; i++) {
      // Calculates fitness
      this.rockets[i].calcFitness();
      // If current fitness is greater than max, then make max eqaul to current
      if (this.rockets[i].fitness > maxfit) {
        maxfit = this.rockets[i].fitness;
      }
    }
    // Normalises fitnesses
    for (var i = 0; i < popSize; i++) {
      this.rockets[i].fitness /= maxfit;
    }
	for(var i = 0; i < popSize; i++){
		total+=this.rockets[i].fitness;
	}
	average=total/popSize;
	console.log(average);

/* this.matingpool = [];
    // Take rockets fitness make in to scale of 1 to 100
    // A rocket with high fitness will highly likely will be in the mating pool
    for (var i = 0; i < popSize; i++) {
      var n = this.rockets[i].fitness * 100;
      for (var j = 0; j < n; j++) {
        this.matingpool.push(this.rockets[i]);
			}	
		}*/
	}
  }
  // Selects appropriate genes for child
  this.selection = function() {
	if(!solution){
    var newRockets = [];
	var parentA;
	var parnetB;
	var child;
	var checked=false;
    for (var i = 0; i < this.rockets.length; i++) {
		    for (var j = 0; j < this.rockets.length; j++){
				if(random()<this.rockets[j].fitness){
					parentA=this.rockets[j].dna;
					break;
					}
			}
			for (var j = 0; j < this.rockets.length; j++){
				if(random()<this.rockets[j].fitness){
					parentB=this.rockets[j].dna;
					break;
					}
				
			}
		child = parentA.crossover(parentB);
		child.mutation(average);
		
      // Picks random dna
      //var parentA = random(this.matingpool).dna;
      //var parentB = random(this.matingpool).dna;
      // Creates child by using crossover function
      // Creates new rocket with child dna
		newRockets[i] = new Rocket(child);
    }
    // This instance of rockets are the new rockets
    this.rockets = newRockets;
	}
  }
  // Calls for update and show functions
  this.run = function(array) {
    for (var i = 0; i < popSize; i++) {
      this.rockets[i].update(array);
      // Displays rockets to screen
      this.rockets[i].show();
			}
		}
}

Genetic Alogorithm

Click on the canvas to place walls

Select Sample Size

Frames:

Generation:

The Model

Class for Rocket Object

Class for DNA Object

Class for Population Object

The Explanation