ライフゲームのJavaScript実装、コアのみ

LifeGame.js

class LifeGame {
  constructor (w, h) {
    this.w = w;
    this.h = h;
    this.board = [...Array(w)].map(()=>[...Array(h)].map(()=>Math.random()>0.5)); // Init board
  }
  step () {
    const newBoard = [];
    for (const [x,w] of enumerate(this.board)) {
      const wArr = [];
      newBoard.push(wArr);
      for (const [y,h] of enumerate(w)) {
        const countedCellsAround = this.countCellsAround(x,y);
        if (h) {
          // 生きている
          if (countedCellsAround === 2 || countedCellsAround === 3) {
            wArr.push(true); // 生存
          }else if (countedCellsAround <= 1) {
            wArr.push(false); // 過疎
          }else {
            wArr.push(false); // 過密
          }
        } else {
          // 死んでいる
          if (countedCellsAround === 3) {
            wArr.push(true); // 誕生
          } else {
            wArr.push(false); // 死んだまま
          }
        }
      }
    }
    this.board = newBoard;
  }
  countCellsAround (x, y) {
    const area = [[-1, -1], [-1, 0], [-1, 1], [0, -1], [0, 1], [1, -1], [1, 0], [1, 1]];
    let count = 0;
    for (const [biasX, biasY] of area) {
      let indexX = x + biasX;
      let indexY = y + biasY;
      if (indexX >= this.w) {
        indexX = 0;
      }
      if (indexX >= this.y) {
        indexY = 0;
      }
      if (this.board.at(indexX).at(indexY)) {
        count += 1;
      }
    }
    return count;
  }
}