MENU: 0,

  GAME: 1,

  GAME_OVER: 2

};

​

function getSpritePosition(row, col, w, h) {

  let dx = col * w;

  let dy = row * h;

  // let dx = int(col * w + w / 2);

  // let dy = int(row * h + h / 2);

  return { dx: dx, dy: dy };

}

​

function getRandomInt(min, max) {

  min = Math.ceil(min);

  max = Math.floor(max);

  return Math.floor(Math.random() * (max - min) + min);

}

​

class Block {

  constructor(

    row,

    col,

    width,

    height,

    _color,

    isBlock,

    isFood = false,

    dirX = 0,

    dirY = 0

  ) {

    this.row = row;

    this.col = col;

    this.width = width;

    this.height = height;

    this._color = _color;

    this.isBlock = isBlock;

    this.isFood = isFood;

    if (!isBlock && !isFood)

      this.isPlayer = true;

    this.direction = createVector(dirX, dirY);

​

    this.alive = 20;

  }

​

  updateDirection(x, y) {

    this.direction.x = x;

    this.direction.y = y;

  }

​

  update() {

    this.row += this.direction.y;

    this.col += this.direction.x;

​

    if (this.isFood) {

      this.alive--;

    }

  }

​

  draw() {

    noStroke();

    fill(this._color);

​

    let pos = getSpritePosition(this.row, this.col, this.width, this.height);

    rect(pos.dx, pos.dy, this.width, this.height);

  }

}

​

let grid;

let player;

let food;

let score;

let w, h;

let rows, cols;

let offset;

let entities;

let state;

​

let bg, fg;

​

function keyPressed() {

  switch (keyCode) {

    case UP_ARROW:

      player.updateDirection(0, -1);

      break;

    case DOWN_ARROW:

      player.updateDirection(0, 1);

      break;

    case LEFT_ARROW:

      player.updateDirection(-1, 0);

      break;

    case RIGHT_ARROW:

      player.updateDirection(1, 0);

      break;

    default:

      break;

  }

}

​

function setup() {

  score = 0;

  w = 16;

  h = 16;

  offset = 4; // offset between grid cells

​

  rows = 24;

  cols = 24;

​

  // nokia-ish screen colors

  bg = "#9bca1d";

  fg = "#203d04";

  state = STATES.MENU;

​

  entities = [];

​

  // player

  player = new Block(

    int(rows / 2) - 1,

    int(cols / 2) - 1,

    w,

    h,

    fg,

    false,

    false,

    (dirX = 1)

  );

  player.tail = []; // player is special

  player.tailDirs = [];

  entities.push(player);

​

  // walls

  for (let r = 0; r < rows; r++) {

    for (let c = 0; c < cols; c++) {

      if (r == 0 || c == 0 || r == rows - 1 || c == cols - 1)

        entities.push(

          new Block(r, c, w, h, fg, (isWall = true), (isFood = false))

        );

    }

  }

​

  createCanvas(cols * w, rows * h);

  // createCanvas(cols * w + (cols + 1) * offset, rows * h + (rows + 1) * offset);

​

  frameRate(2);

}

​

function draw() {

  background(bg);

​

  entities.forEach(function (e, index, object) {

    if (!e.isWall) {

      e.update();

​

      // remove if food and timer is gone

      if (e.isFood && e.alive <= 0) entities.splice(index, 1);

    }

    e.draw();

  });

  if (random() > 0.95) {

    let _r = getRandomInt(0, rows);

    let _c = getRandomInt(0, cols);

​

    entities.push(

      new Block(_r, _c, w, h, fg, (isWall = false), (isFood = true))

    );

  }

}

​