README.md

Puyo Puyo

Puyo-Puyo is a Tetris-like puzzle video game built using JavaScript and HTML5 Canvas.

Play Puyo Puyo

The game follows these rules:

1. Combine 4 or more of the same color pieces to clear
2. Velocity of the Puyo will increase as the time goes
3. The goal is to get the highest score.

Features and Implementation

Game rendering

• Incorporated HTML5 Canvas to render objects, and used window.requestAnimationFrame method to show smooth and polished motions of the objects

lib/game_view.js:

play() {
  this.game.step();
  this.game.draw(this.ctx, this.nextPuyoCtx);

  if (!this.game.over) {
    this.gameStart = requestAnimationFrame(this.play);
  }

  this.game.gameOver();
}

Puyo clear logic

This is where things get difficult. In Tetris, clearing logic is simple, clear lines. However, in Puyo Puyo, you have to check the entire board to see where four or more of the same color Puyos are together.

This is where Breadth First Search comes to rescue:

lib/board.js:

clearPuyos() {
  this.puyos.forEach((puyo) => {
    let count = 1;
    let queue = [puyo];
    let puyoToDestroy = [puyo];
    let el;
    while (queue.length > 0) {
      el = queue.shift();
      el.neighbors(this).forEach( (pos) => {
        const neighbor = this.grid[pos[1]][pos[0]]
        if (neighbor &&
            el.color === neighbor.color &&
            !puyoToDestroy.includes(neighbor)) {
          count += 1;
          queue.push(neighbor);
          puyoToDestroy.push(neighbor);
        }
      });
    }

    if (count >= 4) {
      this.score += puyoToDestroy.length * 10;

      puyoToDestroy.forEach((puyoToDelete) => {
        this.grid[puyoToDelete.row][puyoToDelete.col] = null;
        const idx = this.puyos.indexOf(puyoToDelete);
        this.puyos.splice(idx, 1);
      });
    }
  });
}

Bonus features

• Add rock pieces that will only disappear if neighboring pieces pop to make the game more difficult
• Create AI player to vs against.
• Make it multiplayer game to vs against each other.