scriptP5.js

//Inspiration from Daniel Shiffman
//Coding Train


var twitPopulation;//
var lifeSpan = 400;//

var count = 0;//
var target;//
var maxforce = 0.2;//

var rx = 100;//
var ry = 150;//
var rw = 200;//
var rh = 10;//

function setup() {
    var canvas = createCanvas(windowWidth/2, windowHeight);
    canvas.parent('sketch-holder');
    twitPopulation = new Population();
    target = createVector(width/2, 50);
}


function draw() {
    background(0);
    twitPopulation.run();
    
    count++;  
    if (count == lifeSpan) {
        twitPopulation.evaluate();
        twitPopulation.selection();
        count = 0;
    }

    // fill(255);
    // rect(rx, ry, rw, rh);

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

function Population() {

    this.twitRocket = [];
    this.popsize = 15;
    this.matingpool = [];

    for ( var i = 0; i < this.popsize; i++) {
        this.twitRocket[i] = new Rocket(); //
    }

    //DNA Selection 
    this.evaluate = function() {

        var maxfit = 0;

        for (var i = 0; i < this.popsize; i++) {
            this.twitRocket[i].calcFitness();
            if (this.twitRocket[i].fitness > maxfit) {
                maxfit = this.twitRocket[i].fitness;
            }
        }

        for (var i = 0; i < this.popsize; i++) {
            this.twitRocket[i].fitness /= maxfit;
        }

        this.matingpool = [];

        for (var i = 0; i < this.popsize; i++) {
            var n = this.twitRocket[i].fitness * 100;
            for (var j = 0; j < n; j++) {
                this.matingpool.push(this.twitRocket[i]);
            }
        }
    }

    this.selection = function() {
        var newTwitRocket = [];
        for (var i = 0; i < this.twitRocket.length; i++) {
            var parentA = random(this.matingpool).dna;
            var parentB = random(this.matingpool).dna;

            var child = parentA.crossover(parentB);
            child.mutation();
            newTwitRocket[i] = new Rocket(child);
        }
        this.twitRocket = newTwitRocket;

    }

    this.run = function() {
        for ( var i = 0; i < this.popsize; i++) {
            this.twitRocket[i].update();
            this.twitRocket[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);  // force of vectors
        }
    }

    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(); // velocity start at 0
    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();
        }
        // 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(0, 172, 237);
        translate(this.pos.x, this.pos.y);
        rotate(this.vel.heading());
        rectMode(CENTER);        
        // rect(0, 0, 30, 10); //object structure 
        ellipse(0, 0, 25, 25);
        pop();
    }



}