Netbyzz

#A061
2d Snack Game

HTML :

<!-- CODE = #A061 -->
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>NETBYZZ A061</title>
    <link rel="stylesheet" href="style.css">
  </head>
  <body>
    <div class="score">0</div>
    <div class="stage"></div>
    <script src="script.js"></script>
  </body>
</html>

CSS :

* {
  box-sizing: border-box;
}

html,
body {
  background-color: #000;
  height: 100%;
}

body {
  background: #222;
  background: radial-gradient(#333, #111);
  background-position: center center;
  background-repeat: no-repeat;
  background-size: cover;
  color: #fff;
  font: 100%/1.5 sans-serif;
  overflow: hidden;
}

.score {
  color: rgba(255, 255, 255, 0.5);
  font-size: 16px;
  font-weight: bold;
  padding-top: 5px;
  text-align: center;
}

.stage {
  bottom: 0;
  left: 0;
  margin: auto;
  position: absolute;
  right: 0;
  top: 0;
  z-index: 2;
}

.tile {
  background: rgba(0, 0, 0, 0.15);
  position: absolute;
  transition-property: box-shadow, opacity, transform;
  transform: translateZ(0);
  transition-duration: 3000ms;
}

.tile:before {
  bottom: 0;
  content: "";
  height: 0;
  left: 0;
  margin: auto;
  opacity: 0;
  position: absolute;
  right: 0;
  top: 0;
  width: 0;
  transition: opacity 300ms;
}

.tile.path:before {
  opacity: 1;
}

.tile.up:before {
  border-bottom: 4px inset rgba(255, 255, 255, 0.15);
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
}

.tile.down:before {
  border-top: 4px inset rgba(255, 255, 255, 0.15);
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
}

.tile.left:before {
  border-right: 4px inset rgba(255, 255, 255, 0.15);
  border-top: 4px solid transparent;
  border-bottom: 4px solid transparent;
}

.tile.right:before {
  border-left: 4px inset rgba(255, 255, 255, 0.15);
  border-top: 4px solid transparent;
  border-bottom: 4px solid transparent;
}

@media (max-width: 900px),
(max-height: 900px) {

  .tile.up:before,
  .tile.down:before,
  .tile.left:before,
  .tile.right:before {
    border-width: 3px;
  }
}

@media (max-width: 500px),
(max-height: 500px) {

  .tile.up:before,
  .tile.down:before,
  .tile.left:before,
  .tile.right:before {
    border-width: 2px;
  }
}

.tile.pressed {
  background: rgba(0, 0, 0, 0.3);
  box-shadow: inset 0 0 10px rgba(0, 0, 0, 0.6);
  transition-duration: 0ms;
}

JS :

(function () {
  "use strict";

  var lastTime = 0;
  var vendors = ["webkit", "moz"];
  for (var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
    window.requestAnimationFrame = window[vendors[x] + "RequestAnimationFrame"];
    window.cancelAnimationFrame =
      window[vendors[x] + "CancelAnimationFrame"] ||
      window[vendors[x] + "CancelRequestAnimationFrame"];
  }

  if (!window.requestAnimationFrame) {
    window.requestAnimationFrame = function (callback, element) {
      var currTime = new Date().getTime();
      var timeToCall = Math.max(0, 16 - (currTime - lastTime));
      var id = window.setTimeout(function () {
        callback(currTime + timeToCall);
      }, timeToCall);
      lastTime = currTime + timeToCall;
      return id;
    };
  }

  if (!window.cancelAnimationFrame) {
    window.cancelAnimationFrame = function (id) {
      clearTimeout(id);
    };
  }
})();

(function () {
  "use strict";

  function hasClass(elem, className) {
    return new RegExp(" " + className + " ").test(" " + elem.className + " ");
  }

  function addClass(elem, className) {
    if (!hasClass(elem, className)) {
      elem.className += " " + className;
    }
  }

  function removeClass(elem, className) {
    var newClass = " " + elem.className.replace(/[\t\r\n]/g, " ") + " ";
    if (hasClass(elem, className)) {
      while (newClass.indexOf(" " + className + " ") >= 0) {
        newClass = newClass.replace(" " + className + " ", " ");
      }
      elem.className = newClass.replace(/^\s+|\s+$/g, "");
    }
  }

  function toggleClass(elem, className) {
    var newClass = " " + elem.className.replace(/[\t\r\n]/g, " ") + " ";
    if (hasClass(elem, className)) {
      while (newClass.indexOf(" " + className + " ") >= 0) {
        newClass = newClass.replace(" " + className + " ", " ");
      }
      elem.className = newClass.replace(/^\s+|\s+$/g, "");
    } else {
      elem.className += " " + className;
    }
  }
})();

g = {};

(function () {
  "use strict";

  g.m = Math;
  g.mathProps =
    "E LN10 LN2 LOG2E LOG10E PI SQRT1_2 SQRT2 abs acos asin atan ceil cos exp floor log round sin sqrt tan atan2 pow max min".split(
      " "
    );
  for (var i = 0; i < g.mathProps.length; i++) {
    g[g.mathProps[i]] = g.m[g.mathProps[i]];
  }
  g.m.TWO_PI = g.m.PI * 2;

  g.isset = function (prop) {
    return typeof prop != "undefined";
  };

  g.log = function () {
    if (g.isset(g.config) && g.config.debug && window.console) {
      console.log(Array.prototype.slice.call(arguments));
    }
  };
})();

(function () {
  "use strict";

  g.Group = function () {
    this.collection = [];
    this.length = 0;
  };

  g.Group.prototype.add = function (item) {
    this.collection.push(item);
    this.length++;
  };

  g.Group.prototype.remove = function (index) {
    if (index < this.length) {
      this.collection.splice(index, 1);
      this.length--;
    }
  };

  g.Group.prototype.empty = function () {
    this.collection.length = 0;
    this.length = 0;
  };

  g.Group.prototype.each = function (action, asc) {
    var asc = asc || 0,
      i;
    if (asc) {
      for (i = 0; i < this.length; i++) {
        this.collection[i][action](i);
      }
    } else {
      i = this.length;
      while (i--) {
        this.collection[i][action](i);
      }
    }
  };
})();

(function () {
  "use strict";

  g.util = {};

  g.util.rand = function (min, max) {
    return g.m.random() * (max - min) + min;
  };

  g.util.randInt = function (min, max) {
    return g.m.floor(g.m.random() * (max - min + 1)) + min;
  };
})();

(function () {
  "use strict";

  g.states = {};

  g.addState = function (state) {
    g.states[state.name] = state;
  };

  g.setState = function (name) {
    if (g.state) {
      g.states[g.state].exit();
    }
    g.state = name;
    g.states[g.state].init();
  };

  g.currentState = function () {
    return g.states[g.state];
  };
})();

(function () {
  "use strict";

  g.Time = function () {
    this.reset();
  };

  g.Time.prototype.reset = function () {
    this.now = Date.now();
    this.last = Date.now();
    this.delta = 60;
    this.ndelta = 1;
    this.elapsed = 0;
    this.nelapsed = 0;
    this.tick = 0;
  };

  g.Time.prototype.update = function () {
    this.now = Date.now();
    this.delta = this.now - this.last;
    this.ndelta = Math.min(Math.max(this.delta / (1000 / 60), 0.0001), 10);
    this.elapsed += this.delta;
    this.nelapsed += this.ndelta;
    this.last = this.now;
    this.tick++;
  };
})();

(function () {
  "use strict";

  g.Grid = function (cols, rows) {
    this.cols = cols;
    this.rows = rows;
    this.tiles = [];
    for (var x = 0; x < cols; x++) {
      this.tiles[x] = [];
      for (var y = 0; y < rows; y++) {
        this.tiles[x].push("empty");
      }
    }
  };

  g.Grid.prototype.get = function (x, y) {
    return this.tiles[x][y];
  };

  g.Grid.prototype.set = function (x, y, val) {
    this.tiles[x][y] = val;
  };
})();

(function () {
  "use strict";

  g.BoardTile = function (opt) {
    this.parentState = opt.parentState;
    this.parentGroup = opt.parentGroup;
    this.col = opt.col;
    this.row = opt.row;
    this.x = opt.x;
    this.y = opt.y;
    this.z = 0;
    this.w = opt.w;
    this.h = opt.h;
    this.elem = document.createElement("div");
    this.elem.style.position = "absolute";
    this.elem.className = "tile";
    this.parentState.stageElem.appendChild(this.elem);
    this.classes = {
      pressed: 0,
      path: 0,
      up: 0,
      down: 0,
      left: 0,
      right: 0,
    };
    this.updateDimensions();
  };

  g.BoardTile.prototype.update = function () {
    for (var k in this.classes) {
      if (this.classes[k]) {
        this.classes[k]--;
      }
    }

    if (
      this.parentState.food.tile.col == this.col ||
      this.parentState.food.tile.row == this.row
    ) {
      this.classes.path = 1;
      if (this.col < this.parentState.food.tile.col) {
        this.classes.right = 1;
      } else {
        this.classes.right = 0;
      }
      if (this.col > this.parentState.food.tile.col) {
        this.classes.left = 1;
      } else {
        this.classes.left = 0;
      }
      if (this.row > this.parentState.food.tile.row) {
        this.classes.up = 1;
      } else {
        this.classes.up = 0;
      }
      if (this.row < this.parentState.food.tile.row) {
        this.classes.down = 1;
      } else {
        this.classes.down = 0;
      }
    } else {
      this.classes.path = 0;
    }

    if (this.parentState.food.eaten) {
      this.classes.path = 0;
    }
  };

  g.BoardTile.prototype.updateDimensions = function () {
    this.x = this.col * this.parentState.tileWidth;
    this.y = this.row * this.parentState.tileHeight;
    this.w = this.parentState.tileWidth - this.parentState.spacing;
    this.h = this.parentState.tileHeight - this.parentState.spacing;
    this.elem.style.left = this.x + "px";
    this.elem.style.top = this.y + "px";
    this.elem.style.width = this.w + "px";
    this.elem.style.height = this.h + "px";
  };

  g.BoardTile.prototype.render = function () {
    var classString = "";
    for (var k in this.classes) {
      if (this.classes[k]) {
        classString += k + " ";
      }
    }
    this.elem.className = "tile " + classString;
  };
})();

(function () {
  "use strict";

  g.SnakeTile = function (opt) {
    this.parentState = opt.parentState;
    this.parentGroup = opt.parentGroup;
    this.col = opt.col;
    this.row = opt.row;
    this.x = opt.x;
    this.y = opt.y;
    this.w = opt.w;
    this.h = opt.h;
    this.color = null;
    this.scale = 1;
    this.rotation = 0;
    this.blur = 0;
    this.alpha = 1;
    this.borderRadius = 0;
    this.borderRadiusAmount = 0;
    this.elem = document.createElement("div");
    this.elem.style.position = "absolute";
    this.parentState.stageElem.appendChild(this.elem);
  };

  g.SnakeTile.prototype.update = function (i) {
    this.x = this.col * this.parentState.tileWidth;
    this.y = this.row * this.parentState.tileHeight;
    if (i == 0) {
      this.color = "#fff";
      this.blur =
        this.parentState.dimAvg * 0.03 +
        Math.sin(this.parentState.time.elapsed / 200) *
          this.parentState.dimAvg *
          0.015;
      if (this.parentState.snake.dir == "n") {
        this.borderRadius =
          this.borderRadiusAmount + "% " + this.borderRadiusAmount + "% 0 0";
      } else if (this.parentState.snake.dir == "s") {
        this.borderRadius =
          "0 0 " +
          this.borderRadiusAmount +
          "% " +
          this.borderRadiusAmount +
          "%";
      } else if (this.parentState.snake.dir == "e") {
        this.borderRadius =
          "0 " +
          this.borderRadiusAmount +
          "% " +
          this.borderRadiusAmount +
          "% 0";
      } else if (this.parentState.snake.dir == "w") {
        this.borderRadius =
          this.borderRadiusAmount + "% 0 0 " + this.borderRadiusAmount + "%";
      }
    } else {
      this.color = "#fff";
      this.blur = 0;
      this.borderRadius = "0";
    }
    this.alpha = 1 - (i / this.parentState.snake.tiles.length) * 0.6;
    this.rotation =
      (this.parentState.snake.justAteTick /
        this.parentState.snake.justAteTickMax) *
      90;
    this.scale =
      1 +
      (this.parentState.snake.justAteTick /
        this.parentState.snake.justAteTickMax) *
        1;
  };

  g.SnakeTile.prototype.updateDimensions = function () {
    this.w = this.parentState.tileWidth - this.parentState.spacing;
    this.h = this.parentState.tileHeight - this.parentState.spacing;
  };

  g.SnakeTile.prototype.render = function (i) {
    this.elem.style.left = this.x + "px";
    this.elem.style.top = this.y + "px";
    this.elem.style.width = this.w + "px";
    this.elem.style.height = this.h + "px";
    this.elem.style.backgroundColor = "rgba(255, 255, 255, " + this.alpha + ")";
    this.elem.style.boxShadow = "0 0 " + this.blur + "px #fff";
    this.elem.style.borderRadius = this.borderRadius;
  };
})();

(function () {
  "use strict";

  g.FoodTile = function (opt) {
    this.parentState = opt.parentState;
    this.parentGroup = opt.parentGroup;
    this.col = opt.col;
    this.row = opt.row;
    this.x = opt.x;
    this.y = opt.y;
    this.w = opt.w;
    this.h = opt.h;
    this.blur = 0;
    this.scale = 1;
    this.hue = 100;
    this.opacity = 0;
    this.elem = document.createElement("div");
    this.elem.style.position = "absolute";
    this.parentState.stageElem.appendChild(this.elem);
  };

  g.FoodTile.prototype.update = function () {
    this.x = this.col * this.parentState.tileWidth;
    this.y = this.row * this.parentState.tileHeight;
    this.blur =
      this.parentState.dimAvg * 0.03 +
      Math.sin(this.parentState.time.elapsed / 200) *
        this.parentState.dimAvg *
        0.015;
    this.scale = 0.8 + Math.sin(this.parentState.time.elapsed / 200) * 0.2;

    if (this.parentState.food.birthTick || this.parentState.food.deathTick) {
      if (this.parentState.food.birthTick) {
        this.opacity = 1 - (this.parentState.food.birthTick / 1) * 1;
      } else {
        this.opacity = (this.parentState.food.deathTick / 1) * 1;
      }
    } else {
      this.opacity = 1;
    }
  };

  g.FoodTile.prototype.updateDimensions = function () {
    this.w = this.parentState.tileWidth - this.parentState.spacing;
    this.h = this.parentState.tileHeight - this.parentState.spacing;
  };

  g.FoodTile.prototype.render = function () {
    this.elem.style.left = this.x + "px";
    this.elem.style.top = this.y + "px";
    this.elem.style.width = this.w + "px";
    this.elem.style.height = this.h + "px";
    this.elem.style["transform"] = "translateZ(0) scale(" + this.scale + ")";
    this.elem.style.backgroundColor = "hsla(" + this.hue + ", 100%, 60%, 1)";
    this.elem.style.boxShadow =
      "0 0 " + this.blur + "px hsla(" + this.hue + ", 100%, 60%, 1)";
    this.elem.style.opacity = this.opacity;
  };
})();

(function () {
  "use strict";

  g.Snake = function (opt) {
    this.parentState = opt.parentState;
    (this.dir = "e"), (this.currDir = this.dir);
    this.tiles = [];
    for (var i = 0; i < 5; i++) {
      this.tiles.push(
        new g.SnakeTile({
          parentState: this.parentState,
          parentGroup: this.tiles,
          col: 8 - i,
          row: 3,
          x: (8 - i) * opt.parentState.tileWidth,
          y: 3 * opt.parentState.tileHeight,
          w: opt.parentState.tileWidth - opt.parentState.spacing,
          h: opt.parentState.tileHeight - opt.parentState.spacing,
        })
      );
    }
    this.last = 0;
    this.updateTick = 10;
    this.updateTickMax = this.updateTick;
    this.updateTickLimit = 3;
    this.updateTickChange = 0.2;
    this.deathFlag = 0;
    this.justAteTick = 0;
    this.justAteTickMax = 1;
    this.justAteTickChange = 0.05;

    var i = this.tiles.length;

    while (i--) {
      this.parentState.grid.set(this.tiles[i].col, this.tiles[i].row, "snake");
    }
  };

  g.Snake.prototype.updateDimensions = function () {
    var i = this.tiles.length;
    while (i--) {
      this.tiles[i].updateDimensions();
    }
  };

  g.Snake.prototype.update = function () {
    if (this.parentState.keys.up) {
      if (
        this.dir != "s" &&
        this.dir != "n" &&
        this.currDir != "s" &&
        this.currDir != "n"
      ) {
        this.dir = "n";
      }
    } else if (this.parentState.keys.down) {
      if (
        this.dir != "n" &&
        this.dir != "s" &&
        this.currDir != "n" &&
        this.currDir != "s"
      ) {
        this.dir = "s";
      }
    } else if (this.parentState.keys.right) {
      if (
        this.dir != "w" &&
        this.dir != "e" &&
        this.currDir != "w" &&
        this.currDir != "e"
      ) {
        this.dir = "e";
      }
    } else if (this.parentState.keys.left) {
      if (
        this.dir != "e" &&
        this.dir != "w" &&
        this.currDir != "e" &&
        this.currDir != "w"
      ) {
        this.dir = "w";
      }
    }

    this.parentState.keys.up = 0;
    this.parentState.keys.down = 0;
    this.parentState.keys.right = 0;
    this.parentState.keys.left = 0;

    this.updateTick += this.parentState.time.ndelta;
    if (this.updateTick >= this.updateTickMax) {
      this.updateTick = this.updateTick - this.updateTickMax;
      this.tiles.unshift(
        new g.SnakeTile({
          parentState: this.parentState,
          parentGroup: this.tiles,
          col: this.tiles[0].col,
          row: this.tiles[0].row,
          x: this.tiles[0].col * this.parentState.tileWidth,
          y: this.tiles[0].row * this.parentState.tileHeight,
          w: this.parentState.tileWidth - this.parentState.spacing,
          h: this.parentState.tileHeight - this.parentState.spacing,
        })
      );
      this.last = this.tiles.pop();
      this.parentState.stageElem.removeChild(this.last.elem);

      this.parentState.boardTiles.collection[
        this.last.col + this.last.row * this.parentState.cols
      ].classes.pressed = 2;

      var i = this.tiles.length;

      while (i--) {
        this.parentState.grid.set(
          this.tiles[i].col,
          this.tiles[i].row,
          "snake"
        );
      }
      this.parentState.grid.set(this.last.col, this.last.row, "empty");

      if (this.dir == "n") {
        this.currDir = "n";
        this.tiles[0].row -= 1;
      } else if (this.dir == "s") {
        this.currDir = "s";
        this.tiles[0].row += 1;
      } else if (this.dir == "w") {
        this.currDir = "w";
        this.tiles[0].col -= 1;
      } else if (this.dir == "e") {
        this.currDir = "e";
        this.tiles[0].col += 1;
      }

      this.wallFlag = false;
      if (this.tiles[0].col >= this.parentState.cols) {
        this.tiles[0].col = 0;
        this.wallFlag = true;
      }
      if (this.tiles[0].col < 0) {
        this.tiles[0].col = this.parentState.cols - 1;
        this.wallFlag = true;
      }
      if (this.tiles[0].row >= this.parentState.rows) {
        this.tiles[0].row = 0;
        this.wallFlag = true;
      }
      if (this.tiles[0].row < 0) {
        this.tiles[0].row = this.parentState.rows - 1;
        this.wallFlag = true;
      }

      if (
        this.parentState.grid.get(this.tiles[0].col, this.tiles[0].row) ==
        "snake"
      ) {
        this.deathFlag = 1;
        clearTimeout(this.foodCreateTimeout);
      }

      if (
        this.parentState.grid.get(this.tiles[0].col, this.tiles[0].row) ==
        "food"
      ) {
        this.tiles.push(
          new g.SnakeTile({
            parentState: this.parentState,
            parentGroup: this.tiles,
            col: this.last.col,
            row: this.last.row,
            x: this.last.col * this.parentState.tileWidth,
            y: this.last.row * this.parentState.tileHeight,
            w: this.parentState.tileWidth - this.parentState.spacing,
            h: this.parentState.tileHeight - this.parentState.spacing,
          })
        );
        if (this.updateTickMax - this.updateTickChange > this.updateTickLimit) {
          this.updateTickMax -= this.updateTickChange;
        }
        this.parentState.score++;
        this.parentState.scoreElem.innerHTML = this.parentState.score;
        this.justAteTick = this.justAteTickMax;

        this.parentState.food.eaten = 1;
        this.parentState.stageElem.removeChild(this.parentState.food.tile.elem);

        var _this = this;

        this.foodCreateTimeout = setTimeout(function () {
          _this.parentState.food = new g.Food({
            parentState: _this.parentState,
          });
        }, 300);
      }

      if (this.deathFlag) {
        g.setState("play");
      }
    }

    var i = this.tiles.length;
    while (i--) {
      this.tiles[i].update(i);
    }

    if (this.justAteTick > 0) {
      this.justAteTick -= this.justAteTickChange;
    } else if (this.justAteTick < 0) {
      this.justAteTick = 0;
    }
  };

  g.Snake.prototype.render = function () {
    var i = this.tiles.length;
    while (i--) {
      this.tiles[i].render(i);
    }
  };
})();

(function () {
  "use strict";

  g.Food = function (opt) {
    this.parentState = opt.parentState;
    this.tile = new g.FoodTile({
      parentState: this.parentState,
      col: 0,
      row: 0,
      x: 0,
      y: 0,
      w: opt.parentState.tileWidth - opt.parentState.spacing,
      h: opt.parentState.tileHeight - opt.parentState.spacing,
    });
    this.reset();
    this.eaten = 0;
    this.birthTick = 1;
    this.deathTick = 0;
    this.birthTickChange = 0.025;
    this.deathTickChange = 0.05;
  };

  g.Food.prototype.reset = function () {
    var empty = [];
    for (var x = 0; x < this.parentState.cols; x++) {
      for (var y = 0; y < this.parentState.rows; y++) {
        var tile = this.parentState.grid.get(x, y);
        if (tile == "empty") {
          empty.push({ x: x, y: y });
        }
      }
    }
    var newTile = empty[g.util.randInt(0, empty.length - 1)];
    this.tile.col = newTile.x;
    this.tile.row = newTile.y;
  };

  g.Food.prototype.updateDimensions = function () {
    this.tile.updateDimensions();
  };

  g.Food.prototype.update = function () {
    this.tile.update();

    if (this.birthTick > 0) {
      this.birthTick -= this.birthTickChange;
    } else if (this.birthTick < 0) {
      this.birthTick = 0;
    }

    this.parentState.grid.set(this.tile.col, this.tile.row, "food");
  };

  g.Food.prototype.render = function () {
    this.tile.render();
  };
})();

(function () {
  "use strict";

  function StatePlay() {
    this.name = "play";
  }

  StatePlay.prototype.init = function () {
    this.scoreElem = document.querySelector(".score");
    this.stageElem = document.querySelector(".stage");
    this.dimLong = 28;
    this.dimShort = 16;
    this.padding = 0.25;
    this.boardTiles = new g.Group();
    this.keys = {};
    this.foodCreateTimeout = null;
    this.score = 0;
    this.scoreElem.innerHTML = this.score;
    this.time = new g.Time();
    this.getDimensions();
    if (this.winWidth < this.winHeight) {
      this.rows = this.dimLong;
      this.cols = this.dimShort;
    } else {
      this.rows = this.dimShort;
      this.cols = this.dimLong;
    }
    this.spacing = 1;
    this.grid = new g.Grid(this.cols, this.rows);
    this.resize();
    this.createBoardTiles();
    this.bindEvents();
    this.snake = new g.Snake({
      parentState: this,
    });
    this.food = new g.Food({
      parentState: this,
    });
  };

  StatePlay.prototype.getDimensions = function () {
    this.winWidth = window.innerWidth;
    this.winHeight = window.innerHeight;
    this.activeWidth = this.winWidth - this.winWidth * this.padding;
    this.activeHeight = this.winHeight - this.winHeight * this.padding;
  };

  StatePlay.prototype.resize = function () {
    var _this = g.currentState();

    _this.getDimensions();

    _this.stageRatio = _this.rows / _this.cols;

    if (_this.activeWidth > _this.activeHeight / _this.stageRatio) {
      _this.stageHeight = _this.activeHeight;
      _this.stageElem.style.height = _this.stageHeight + "px";
      _this.stageWidth = Math.floor(_this.stageHeight / _this.stageRatio);
      _this.stageElem.style.width = _this.stageWidth + "px";
    } else {
      _this.stageWidth = _this.activeWidth;
      _this.stageElem.style.width = _this.stageWidth + "px";
      _this.stageHeight = Math.floor(_this.stageWidth * _this.stageRatio);
      _this.stageElem.style.height = _this.stageHeight + "px";
    }

    _this.tileWidth = ~~(_this.stageWidth / _this.cols);
    _this.tileHeight = ~~(_this.stageHeight / _this.rows);
    _this.dimAvg = (_this.activeWidth + _this.activeHeight) / 2;
    _this.spacing = Math.max(1, ~~(_this.dimAvg * 0.0025));

    _this.stageElem.style.marginTop =
      -_this.stageElem.offsetHeight / 2 + _this.headerHeight / 2 + "px";

    _this.boardTiles.each("updateDimensions");
    _this.snake !== undefined && _this.snake.updateDimensions();
    _this.food !== undefined && _this.food.updateDimensions();
  };

  StatePlay.prototype.createBoardTiles = function () {
    for (var y = 0; y < this.rows; y++) {
      for (var x = 0; x < this.cols; x++) {
        this.boardTiles.add(
          new g.BoardTile({
            parentState: this,
            parentGroup: this.boardTiles,
            col: x,
            row: y,
            x: x * this.tileWidth,
            y: y * this.tileHeight,
            w: this.tileWidth - this.spacing,
            h: this.tileHeight - this.spacing,
          })
        );
      }
    }
  };

  StatePlay.prototype.upOn = function () {
    g.currentState().keys.up = 1;
  };
  StatePlay.prototype.downOn = function () {
    g.currentState().keys.down = 1;
  };
  StatePlay.prototype.rightOn = function () {
    g.currentState().keys.right = 1;
  };
  StatePlay.prototype.leftOn = function () {
    g.currentState().keys.left = 1;
  };
  StatePlay.prototype.upOff = function () {
    g.currentState().keys.up = 0;
  };
  StatePlay.prototype.downOff = function () {
    g.currentState().keys.down = 0;
  };
  StatePlay.prototype.rightOff = function () {
    g.currentState().keys.right = 0;
  };
  StatePlay.prototype.leftOff = function () {
    g.currentState().keys.left = 0;
  };

  StatePlay.prototype.keydown = function (e) {
    e.preventDefault();
    var e = e.keyCode ? e.keyCode : e.which,
      _this = g.currentState();
    if (e === 38 || e === 87) {
      _this.upOn();
    }
    if (e === 39 || e === 68) {
      _this.rightOn();
    }
    if (e === 40 || e === 83) {
      _this.downOn();
    }
    if (e === 37 || e === 65) {
      _this.leftOn();
    }
  };

  StatePlay.prototype.bindEvents = function () {
    var _this = g.currentState();
    window.addEventListener("keydown", _this.keydown, false);
    window.addEventListener("resize", _this.resize, false);
  };

  StatePlay.prototype.step = function () {
    this.boardTiles.each("update");
    this.boardTiles.each("render");
    this.snake.update();
    this.snake.render();
    this.food.update();
    this.food.render();
    this.time.update();
  };

  StatePlay.prototype.exit = function () {
    window.removeEventListener("keydown", this.keydown, false);
    window.removeEventListener("resize", this.resize, false);
    this.stageElem.innerHTML = "";
    this.grid.tiles = null;
    this.time = null;
  };

  g.addState(new StatePlay());
})();

(function () {
  "use strict";

  g.config = {
    title: "Snakely",
    debug: window.location.hash == "#debug" ? 1 : 0,
    state: "play",
  };

  g.setState(g.config.state);

  g.time = new g.Time();

  g.step = function () {
    requestAnimationFrame(g.step);
    g.states[g.state].step();
    g.time.update();
  };

  window.addEventListener("load", g.step, false);
})();
 

Source Code