​

//pode mudar essa variavel para 10, 20, 40, 50, 100...

var scl = 20;

var f;

​

function preload() {

  ponto = loadSound("ponto.wav");

  derrota = loadSound("derrota.wav");

  virada = loadSound("virada.wav");

}

​

function setup() {  

  createCanvas(600, 500);

  s = new Snake();

  s.body.push([0, 0]);

  f = new Food();

  frameRate(10);

  food = createVector(random(width), random(height));

}

​

function draw() {

  background(0);

  drawGrid();

  s.update();

  s.death();

  s.show();

  //verifica se está na mesma posição de f

  s.eat(f);

​

  f.show();

}

​

function keyPressed() {

  //VERIFICA SE NÃO ESTÁ TENTANDO ANDAR PRA TRÁS. PORÉM, SE FOR TAMANHO INICIAL, PERMITE ANDAR PRA TRÁS.

​

  if (keyCode === UP_ARROW && (s.yspeed != 1 || s.body.length == 1)) {

    s.direction(0, -1);

    virada.play();

  } else if (keyCode === DOWN_ARROW && (s.yspeed != -1 || s.body.length == 1)) {

    s.direction(0, 1);

    virada.play();

  } else if (keyCode === LEFT_ARROW && (s.xspeed != 1 || s.body.length == 1)) {

    s.direction(-1, 0);

    virada.play();

  } else if (

    (keyCode === RIGHT_ARROW && s.xspeed != -1) ||

    s.body.length == 1

  ) {

    s.direction(1, 0);

    virada.play();

  }

}

​

function drawGrid() {

  var passoX = floor(width / scl); // 400/20 = 20

  var passoY = floor(height / scl);

  var passoXX = width / passoX; 

  var passoYY = height / passoY;  

  //desenha linhas horizontais

  for (i = 0; i <= height; i = i + passoXX) {

    stroke(50);

    strokeWeight(0.5);

    line(0, i, width, i);

  }

  //desenha linhas verticais

  for (i = 0; i <= width; i = i + passoYY) {

    stroke(50);

    strokeWeight(0.5);

    line(i, 0, i, height);

  }

}

​

function Snake() {

  this.x = 0;

  this.y = 0;

  this.xspeed = 1;

  this.yspeed = 0;

  this.body = [];

​

  this.update = function () {

    this.x = this.x + this.xspeed * scl;

    this.y = this.y + this.yspeed * scl;

​

    //Verifica as extremidadas, fazendo mudar a direção

    if (this.x > width - scl) {

      this.x = 0;

    }

    if (this.x < 0) {

      this.x = width;

    }

    if (this.y > height - scl) {

      this.y = 0;

    }

    if (this.y < 0) {

      this.y = height;

    }

​

    this.x = constrain(this.x, 0, width - scl);

    this.y = constrain(this.y, 0, height - scl);

​

    // Adiciona o novo ponto no array

    this.body.push([this.x, this.y]);

    // Retira o primeiro ponto do array

    this.body.shift();

  };

​

  this.show = function () {

    fill(255);

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

      rect(this.body[i][0], this.body[i][1], scl, scl);

    }

  };

​

  this.direction = function (x, y) {

    this.xspeed = x;

    this.yspeed = y;

  };

​

  this.eat = function (food) {

    if (this.x == food.x && this.y == food.y) {

      this.body.push([this.x, this.y]);      

      food.newFood(s);

      ponto.play();

    }

  };

​

  this.death = function () {

    //maior elemento do array body

    var head = this.body.length - 1;

​

    //iterar através do body exceto o último elemento

    for (var i = 0; i < this.body.length - 1; i++) {

      if (

        this.body[i][0] == this.body[head][0] &&

        this.body[i][1] == this.body[head][1]

      ) {

        //morreu

        console.log("morreu");

        this.x = 0;

        this.y = 0;

        this.body = [];

        this.body.push([0, 0]);

        background(255, 0, 100);

        derrota.play();

      }

    }

  };

}

​

function Food() {

  this.RandomLocationX = function () {

    var cols = width / scl;

    return floor(random() * cols) * scl;

  };

​

  this.RandomLocationY = function () {

    var rows = height / scl;

    return floor(random() * rows) * scl;

  };

​

  this.x = this.RandomLocationX();

  this.y = this.RandomLocationY();

​

  this.newFood = function (s) {

    this.x = this.RandomLocationX();

    this.y = this.RandomLocationY();

​

    for (var i = 0; i < s.body.length; i++) {

      if (s.body[i][0] == this.x && s.body[i][1] == this.y) {

        this.newFood(s);

      }

    }

    this.show();

  };

​

  this.show = function () {

    fill(255, 0, 100);

    rect(this.x, this.y, scl, scl);

  };

}

​