Javascriptでテトリスを作る

Javascriptのサンプルとしてテトリスは定番ですが、そういえば今まで挑戦してなかったの作ってみました。

canvasを使って落下ブロック(テトリミノ)が７種、色が６種のザ定番ぽいものを作ります。

完成品
ソースコード

完成品

Chromeでしか動作確認してません。

a : 左に移動

s : 右に移動

d : 下に移動

f : 右に回転

ソースコード

<!DOCTYPE HTML>
<html>
<head>
    <meta charset="UTF-8">
</head>
<body>
<!-- canvas -->
<canvas id="tetris" width="300" height="600"></canvas>
<script type="text/javascript">
(function() {
    /* 全体のコンフィグ */
    var CONFIG = {
        'width'      : 0,                /* 横幅 */
        'hegith'     : 0,                /* 縦幅 */
        'xsqs'       : 10,               /* 横方眼数 */
        'ysqs'       : 20,               /* 縦方眼数 */
        'color'      : "rgb(65,65,65)",  /* 盤面の色 */
        'grid_color' : "black",          /* 格子の色 */
        'grid_width' : 2,                /* 格子の幅 */
    };

    /* 方眼 */
    var SQUARES;
    var squre = function() {
        this.color = 0;
    };

    /* 色リスト */
    var COLOR = {
        "default" : CONFIG.color,
        "red"     : "rgb(255,0,0)",
        "green"   : "rgb(0,255,0)",
        "blue"    : "rgb(0,0,255)",
        "yellow"  : "rgb(255,255,0)",
        "cyan"    : "rgb(0,255,255)",
        "magenta" : "rgb(255,0,255)",
    };

    var COLOR_LIST = [
        COLOR.red,
        COLOR.green,
        COLOR.blue,
        COLOR.yellow,
        COLOR.cyan,
        COLOR.magenta,
    ];

    /* ブロックの定義 */
    var BLOCK;
    var block = function () {
        this.color = COLOR_LIST[Math.floor(Math.random() * (COLOR_LIST.length))];
        this.shape = BLOCK_LIST[Math.floor(Math.random() * (BLOCK_LIST.length))];
        this.x = (CONFIG.xsqs / 2) - 1;
        this.y = 0;
        return this;
    };

    var BLOCK_BOX = [
        [0,0,0,0],
        [0,1,1,0],
        [0,1,1,0],
        [0,0,0,0]
    ];
    
    var BLOCK_BAR = [
        [1,1,1,1],
        [0,0,0,0],
        [0,0,0,0],
        [0,0,0,0]
    ];

    var BLOCK_LL = [
        [1,1,1,0],
        [1,0,0,0],
        [0,0,0,0],
        [0,0,0,0]
    ];

    var BLOCK_LN = [
        [1,0,0,0],
        [1,1,1,0],
        [0,0,0,0],
        [0,0,0,0]
    ];

    var BLOCK_NL = [
        [1,0,0,0],
        [1,1,0,0],
        [0,1,0,0],
        [0,0,0,0]
    ];

    var BLOCK_NN = [
        [0,1,0,0],
        [1,1,0,0],
        [1,0,0,0],
        [0,0,0,0]
    ];

    var BLOCK_T = [
        [1,0,0,0],
        [1,1,0,0],
        [1,0,0,0],
        [0,0,0,0]
    ];

    var BLOCK_LIST = [
        BLOCK_BOX,
        BLOCK_BAR,
        BLOCK_LL,
        BLOCK_LN,
        BLOCK_NL,
        BLOCK_NN,
        BLOCK_T,
    ];
    
    /* 描画コンテキスト */
    var CTX;

    /* タイマー */
    var fallTimer;

    /* キー入力 */
    var KEY_DOWN = {
        "a"     : 65, /* left */
        "s"     : 83, /* right */
        "d"     : 68, /* down */
        "f"     : 70, /* turn right */
        "left"  : 37,
        "right" : 39,
        "down"  : 40,
        "space" : 32, /* turn right */
    };
    

    /* 初期化処理 */
    function initialize() {

        /* canvasの取得 */
        CTX = document.getElementById("tetris").getContext('2d');
        if (!CTX) {
            return false;
        }

        CONFIG.width = CTX.canvas.width;
        CONFIG.height = CTX.canvas.height;

        /* keydown event */
        document.onkeydown = moveBlock;

        /* 盤面の生成 */
        SQUARES = createSquares(CONFIG);

        /* 落下ブロックの生成 */
        BLOCK = block();

        /* テトリスの起動 */
        drawTetris(CTX, CONFIG, SQUARES, BLOCK);
        fallTimer = setInterval(tetris, 400, CTX, CONFIG, SQUARES, BLOCK);
    }

    /* ブロックの移動 */
   function moveBlock() {
 
        var key = event.keyCode;

        switch(key) {
        case KEY_DOWN.a :
        case KEY_DOWN.left :
            moveLeftBlock();
            break;
        case KEY_DOWN.s :
        case KEY_DOWN.right :
            moveRightBlock();
            break;
        case KEY_DOWN.f :
        case KEY_DOWN.space :
            turnRightBlock();
            break;
        case KEY_DOWN.d :
        case KEY_DOWN.down :
            moveDownBlock();
            break;
        default:
            break;
        }
   }

    /* 左に移動 */
    function moveLeftBlock() {

        var isEnabeMove = true;

        for (var y = 0 ; y < BLOCK.shape[0].length; y++) {
            for (var x = 0; x < BLOCK.shape.length; x++) {

                if (BLOCK.shape[x][y] == 0) {
                    continue;
                }

                /* これ以上左に行けない */
                if (((BLOCK.x + x) <= 0) ||
                    ((SQUARES[BLOCK.x + x - 1][BLOCK.y + y].color != CONFIG.color))) {
                    isEnabeMove = false;
                    break;
                }
            }
        }

        if (isEnabeMove) {
           BLOCK.x--;
        }
    }

    /* 右に移動 */
    function moveRightBlock() {

        isEnabeMove = true;

        for (var y = 0 ; y < BLOCK.shape[0].length; y++) {
            for (var x = 0; x < BLOCK.shape.length; x++) {
                if (BLOCK.shape[x][y] != 0) {
                    /* これ以上右に行けない */
                    if (((BLOCK.x + x) >= (CONFIG.xsqs - 1)) || 
                        ((SQUARES[BLOCK.x + x + 1][BLOCK.y + y].color != CONFIG.color))) {
                        isEnabeMove = false;
                        break;
                    }
                }
            }
        }

       if (isEnabeMove) {
           BLOCK.x++;
       }
    };

    /* 下に加速 */
    function moveDownBlock() {
        if (!isLanded(CONFIG, SQUARES, BLOCK)) {
            BLOCK.y++;
        }
    };

    /* ターンできるか */
    function isEnableToTurn(tmp) {
        for (var x = 0; x < BLOCK.shape.length; x++) {
            for (var y = 0; y < BLOCK.shape[0].length; y++) {
                if (tmp[x][y] != 0) {
                    if (((BLOCK.x + x) < 0) || (CONFIG.xsqs <= (BLOCK.x + x)) ||
                        ((BLOCK.y + y) < 0) || (CONFIG.ysqs <= (BLOCK.y + y)) ||
                        SQUARES[BLOCK.x + x][BLOCK.y + y].color != CONFIG.color) {
                    
                        return false;
                    }
                }
            }
        }
        return true;
    }

    /* ブロックの右回転 */
    function turnRightBlock() {
        
        var tmp = Array(BLOCK.shape.length);
        for (var x = 0; x < BLOCK.shape.length; x++) {
            tmp[x] = Array(BLOCK.shape[0].length);
        }        

        for (var x = 0; x < BLOCK.shape.length; x++) {
            for (var y = 0; y < BLOCK.shape[0].length; y++) {
                tmp[x][y] = BLOCK.shape[y][BLOCK.shape[0].length - 1 - x];
            }
        }
     
        if (isEnableToTurn(tmp)) {
            BLOCK.shape = tmp;
        }
    }

    /* 方眼の作成 */
    function createSquares(c) {
        var sqrs = new Array(c.ysqs);

        for (var y = 0; y < c.ysqs; y++) {
            sqrs[y] = new Array(c.xsqs);
        }
        
        for (var x = 0; x < c.xsqs; x++) {
            for (var y = 0;  y < c.ysqs; y++) {
                sqrs[x][y] = new squre();
                sqrs[x][y].color = c.color;
            }
        }

        return sqrs;
    }

    /* 盤面の描画 */
    function drawTetris(ctx, c, sqrs, blk) {
        drawBack(ctx, c);   
        drawSquare(ctx, c, sqrs);
        drawBlock(ctx, c, blk);
        drawGrid(ctx, c);
    }

    /* 背景の描画 */
    function drawBack(ctx, c) {
        ctx.fillStyle = c.color;
        ctx.fillRect(0, 0, c.width, c.height);
        
        ctx.strokeStyle = c.grid_color;
        ctx.lineWidth = c.grid_width;
        
        ctx.beginPath();
        ctx.stroke();
    }

    /* 格子(グリッド)の描画 */
    function drawGrid(ctx, c) {

        ctx.beginPath();

        /* 縦のグリッド線 */
        for(var x = c.width/c.xsqs; x < c.width; x+= c.width/c.xsqs) {
            ctx.moveTo(x, 0);
            ctx.lineTo(x, c.height);
        } 
        
        /* 横のグリッド線 */
        for(var y = c.height/c.ysqs; y < c.height; y+= c.height/c.ysqs) {
            ctx.moveTo(0, y);
            ctx.lineTo(c.width, y);
        }
        
        ctx.stroke();
    }

    /* 方眼の描画 */
    function drawSquare(ctx, c, blocks) {
        var x_sp; /* 描画開始座標(x) */
        var y_sp; /* 描画開始座標(y) */
        var w; /* 横幅 */
        var h; /* 縦幅 */

        ctx.beginPath();
        for (var x = 0; x < c.xsqs; x++) {
            for (var y = 0; y < c.ysqs; y++) {
                if (blocks[x][y].color == COLOR.default) {
                    continue;
                }
            
                w = (c.width/c.xsqs);
                h = (c.height/c.ysqs);
                x_sp = x * w;
                y_sp = y * h;
                
                ctx.fillStyle = blocks[x][y].color;
                ctx.fillRect(x_sp, y_sp, w, h);
            }
        }
        ctx.stroke();
    };

    /* 落下ブロックの描画 */
    function drawBlock(ctx, c, blk) {
        var width = c.width/c.xsqs;
        var height = c.height/c.ysqs;

        ctx.fillStyle = blk.color;
        for (var x = 0; x < blk.shape.length; x++) {
            for (var y = 0; y < blk.shape[0].length; y++) {
                if (blk.shape[x][y] != 0) {
                    if (((blk.x + x) >= 0) && ((blk.x + x) <= c.xsqs) &&
                        ((blk.y + y) >= 0) && ((blk.y + y) <= c.ysqs)) {
                       
                        ctx.fillRect((blk.x + x) * width, (blk.y + y) * height, 
                                     width, height);
                    }
                }
            }
        }
    };

    /* ブロックの着地 */
    function addBlock2Board(c, squres, blk) {

        /* 盤面に着色 */
        for (var x = 0; x < blk.shape.length; x++) {
            for (var y = 0; y < blk.shape[0].length; y++) {

                if (blk.shape[x][y] == 0) {
                    continue;
                }
            
                if (blk.x + x <= c.xsqs && blk.y + y <= c.ysqs) {
                    squres[blk.x + x][blk.y + y].color = blk.color;
                }
            }
        }
    }

    /* ブロックの落下 */
    function isLanded(c, squres, blk) {

        /* 着地判定 */
        for (var x = 0; x < blk.shape.length; x++) {
            for (var y = 0; y < blk.shape[0].length; y++) {

                if (blk.shape[x][y] != 0) {
                    /* 地面と接触 */
                    if ((blk.y + y) == (c.ysqs - 1)) {
                        return true;
                    }

                    /* 既設ブロックと接触 */
                    if (squres[blk.x + x][blk.y + y + 1].color != c.color) {
                        return true;
                    }
                }
            } 
        }

        /* Not着地 */
        return false;
    }

    /* GameOverですか? */
    function isGameOver(c, squres) {
        for (var x = c.xsqs/2 - 2 ; x < c.xsqs/2 + 2; x++) {
            if (squres[x][0].color != c.color) {
                return true;
            }
        }
            
        return false;
    }

    /* 行削除 */
    function eraseLine(c, squres) {

        for (var y = 0; y < c.ysqs; y++) {
            /* is enable to erase ? */
            var flag = true;
            for (var x = 0; x < c.xsqs; x++) {
                if (squres[x][y].color == c.color) {
                    flag = false;
                    break;
                }
            }

            if(!flag) {
                continue;
            }

            /* do to erase */
            for (var x = 0; x < c.xsqs; x++) {
                squres[x][y].color = c.color;
            }
            
            if (y != 0) {
                for (var y1 = y; y1 != 0; y1--) {
                    for (var x = 0; x < c.xsqs; x++) {
                        squres[x][y1].color = squres[x][y1-1].color;
                    }
                }
            }
        }
    }

    /* main処理 */
    function tetris(ctx, c, squres, blk) {

        if (isLanded(c, squres, blk)) {
            /* ブロックの着地 */
            addBlock2Board(c, squres, blk);

            /* 削除処理 */
            eraseLine(c, squres);

            /* Game Over ? */
            if (isGameOver(c,squres)) {
                drawTetris(ctx, c, squres, blk);
                clearInterval(fallTimer);
            } else {
                /* 新しいブロックの生成 */
                blk = block();
            }
        } else {
            /* 落下 */
            blk.y++;
        }

        /* 盤面の描画 */
        drawTetris(ctx, c, squres, blk);
    }

    window.addEventListener('load', initialize, false);

} )();
</script>
<div>a : 左に移動</div>
<div>s : 右に移動</div>
<div>d : 下に移動</div>
<div>f : 右に回転</div>
</body>
</html>

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<!DOCTYPE HTML>

<html>

<head>

</head>

<body>

(function() {

/* 全体のコンフィグ */

var CONFIG = {

'width' : 0, /* 横幅 */

'hegith' : 0, /* 縦幅 */

'xsqs' : 10, /* 横方眼数 */

'ysqs' : 20, /* 縦方眼数 */

'color' : "rgb(65,65,65)", /* 盤面の色 */

'grid_color' : "black", /* 格子の色 */

'grid_width' : 2, /* 格子の幅 */

};

/* 方眼 */

var SQUARES;

var squre = function() {

this.color = 0;

};

/* 色リスト */

var COLOR = {

"default" : CONFIG.color,

"red" : "rgb(255,0,0)",

"green" : "rgb(0,255,0)",

"blue" : "rgb(0,0,255)",

"yellow" : "rgb(255,255,0)",

"cyan" : "rgb(0,255,255)",

"magenta" : "rgb(255,0,255)",

};

var COLOR_LIST = [

COLOR.red,

COLOR.green,

COLOR.blue,

COLOR.yellow,

COLOR.cyan,

COLOR.magenta,

];

/* ブロックの定義 */

var BLOCK;

var block = function () {

this.color = COLOR_LIST[Math.floor(Math.random() * (COLOR_LIST.length))];

this.shape = BLOCK_LIST[Math.floor(Math.random() * (BLOCK_LIST.length))];

this.x = (CONFIG.xsqs / 2) - 1;

this.y = 0;

return this;

};

var BLOCK_BOX = [

[0,0,0,0],

[0,1,1,0],

[0,0,0,0]

];

var BLOCK_BAR = [

[1,1,1,1],

[0,0,0,0],

[0,0,0,0]

];

var BLOCK_LL = [

[1,1,1,0],

[1,0,0,0],

[0,0,0,0],

[0,0,0,0]

];

var BLOCK_LN = [

[1,0,0,0],

[1,1,1,0],

[0,0,0,0],

[0,0,0,0]

];

var BLOCK_NL = [

[1,0,0,0],

[1,1,0,0],

[0,1,0,0],

[0,0,0,0]

];

var BLOCK_NN = [

[0,1,0,0],

[1,1,0,0],

[1,0,0,0],

[0,0,0,0]

];

var BLOCK_T = [

[1,0,0,0],

[1,1,0,0],

[1,0,0,0],

[0,0,0,0]

];

var BLOCK_LIST = [

BLOCK_BOX,

BLOCK_BAR,

BLOCK_LL,

BLOCK_LN,

BLOCK_NL,

BLOCK_NN,

BLOCK_T,

];

/* 描画コンテキスト */

var CTX;

/* タイマー */

var fallTimer;

/* キー入力 */

var KEY_DOWN = {

"a" : 65, /* left */

"s" : 83, /* right */

"d" : 68, /* down */

"f" : 70, /* turn right */

"left" : 37,

"right" : 39,

"down" : 40,

"space" : 32, /* turn right */

};

/* 初期化処理 */

function initialize() {

/* canvasの取得 */

CTX = document.getElementById("tetris").getContext('2d');

if (!CTX) {

return false;

}

CONFIG.width = CTX.canvas.width;

CONFIG.height = CTX.canvas.height;

/* keydown event */

document.onkeydown = moveBlock;

/* 盤面の生成 */

SQUARES = createSquares(CONFIG);

/* 落下ブロックの生成 */

BLOCK = block();

/* テトリスの起動 */

drawTetris(CTX, CONFIG, SQUARES, BLOCK);

fallTimer = setInterval(tetris, 400, CTX, CONFIG, SQUARES, BLOCK);

}

/* ブロックの移動 */

function moveBlock() {

var key = event.keyCode;

switch(key) {

case KEY_DOWN.a :

case KEY_DOWN.left :

moveLeftBlock();

break;

case KEY_DOWN.s :

case KEY_DOWN.right :

moveRightBlock();

break;

case KEY_DOWN.f :

case KEY_DOWN.space :

turnRightBlock();

break;

case KEY_DOWN.d :

case KEY_DOWN.down :

moveDownBlock();

break;

default:

break;

}

/* 左に移動 */

function moveLeftBlock() {

var isEnabeMove = true;

for (var y = 0 ; y < BLOCK.shape[0].length; y++) {

for (var x = 0; x < BLOCK.shape.length; x++) {

if (BLOCK.shape[x][y] == 0) {

continue;

}

/* これ以上左に行けない */

if (((BLOCK.x + x) <= 0) ||

((SQUARES[BLOCK.x + x - 1][BLOCK.y + y].color != CONFIG.color))) {

isEnabeMove = false;

break;

}

if (isEnabeMove) {

BLOCK.x--;

}

/* 右に移動 */

function moveRightBlock() {

isEnabeMove = true;

for (var y = 0 ; y < BLOCK.shape[0].length; y++) {

for (var x = 0; x < BLOCK.shape.length; x++) {

if (BLOCK.shape[x][y] != 0) {

/* これ以上右に行けない */

if (((BLOCK.x + x) >= (CONFIG.xsqs - 1)) ||

((SQUARES[BLOCK.x + x + 1][BLOCK.y + y].color != CONFIG.color))) {

isEnabeMove = false;

break;

}

if (isEnabeMove) {

BLOCK.x++;

}

};

/* 下に加速 */

function moveDownBlock() {

if (!isLanded(CONFIG, SQUARES, BLOCK)) {

BLOCK.y++;

}

};

/* ターンできるか */

function isEnableToTurn(tmp) {

for (var x = 0; x < BLOCK.shape.length; x++) {

for (var y = 0; y < BLOCK.shape[0].length; y++) {

if (tmp[x][y] != 0) {

if (((BLOCK.x + x) < 0) || (CONFIG.xsqs <= (BLOCK.x + x)) ||

((BLOCK.y + y) < 0) || (CONFIG.ysqs <= (BLOCK.y + y)) ||

SQUARES[BLOCK.x + x][BLOCK.y + y].color != CONFIG.color) {

return false;

}

return true;

}

/* ブロックの右回転 */

function turnRightBlock() {

var tmp = Array(BLOCK.shape.length);

for (var x = 0; x < BLOCK.shape.length; x++) {

tmp[x] = Array(BLOCK.shape[0].length);

}

for (var x = 0; x < BLOCK.shape.length; x++) {

for (var y = 0; y < BLOCK.shape[0].length; y++) {

tmp[x][y] = BLOCK.shape[y][BLOCK.shape[0].length - 1 - x];

}

if (isEnableToTurn(tmp)) {

BLOCK.shape = tmp;

}

/* 方眼の作成 */

function createSquares(c) {

var sqrs = new Array(c.ysqs);

for (var y = 0; y < c.ysqs; y++) {

sqrs[y] = new Array(c.xsqs);

}

for (var x = 0; x < c.xsqs; x++) {

for (var y = 0; y < c.ysqs; y++) {

sqrs[x][y] = new squre();

sqrs[x][y].color = c.color;

}

return sqrs;

}

/* 盤面の描画 */

function drawTetris(ctx, c, sqrs, blk) {

drawBack(ctx, c);

drawSquare(ctx, c, sqrs);

drawBlock(ctx, c, blk);

drawGrid(ctx, c);

}

/* 背景の描画 */

function drawBack(ctx, c) {

ctx.fillStyle = c.color;

ctx.fillRect(0, 0, c.width, c.height);

ctx.strokeStyle = c.grid_color;

ctx.lineWidth = c.grid_width;

ctx.beginPath();

ctx.stroke();

}

/* 格子(グリッド)の描画 */

function drawGrid(ctx, c) {

ctx.beginPath();

/* 縦のグリッド線 */

for(var x = c.width/c.xsqs; x < c.width; x+= c.width/c.xsqs) {

ctx.moveTo(x, 0);

ctx.lineTo(x, c.height);

}

/* 横のグリッド線 */

for(var y = c.height/c.ysqs; y < c.height; y+= c.height/c.ysqs) {

ctx.moveTo(0, y);

ctx.lineTo(c.width, y);

}

ctx.stroke();

}

/* 方眼の描画 */

function drawSquare(ctx, c, blocks) {

var x_sp; /* 描画開始座標(x) */

var y_sp; /* 描画開始座標(y) */

var w; /* 横幅 */

var h; /* 縦幅 */

ctx.beginPath();

for (var x = 0; x < c.xsqs; x++) {

for (var y = 0; y < c.ysqs; y++) {

if (blocks[x][y].color == COLOR.default) {

continue;

}

w = (c.width/c.xsqs);

h = (c.height/c.ysqs);

x_sp = x * w;

y_sp = y * h;

ctx.fillStyle = blocks[x][y].color;

ctx.fillRect(x_sp, y_sp, w, h);

}

ctx.stroke();

};

/* 落下ブロックの描画 */

function drawBlock(ctx, c, blk) {

var width = c.width/c.xsqs;

var height = c.height/c.ysqs;

ctx.fillStyle = blk.color;

for (var x = 0; x < blk.shape.length; x++) {

for (var y = 0; y < blk.shape[0].length; y++) {

if (blk.shape[x][y] != 0) {

if (((blk.x + x) >= 0) && ((blk.x + x) <= c.xsqs) &&

((blk.y + y) >= 0) && ((blk.y + y) <= c.ysqs)) {

ctx.fillRect((blk.x + x) * width, (blk.y + y) * height,

width, height);

}

};

/* ブロックの着地 */

function addBlock2Board(c, squres, blk) {

/* 盤面に着色 */

for (var x = 0; x < blk.shape.length; x++) {

for (var y = 0; y < blk.shape[0].length; y++) {

if (blk.shape[x][y] == 0) {

continue;

}

if (blk.x + x <= c.xsqs && blk.y + y <= c.ysqs) {

squres[blk.x + x][blk.y + y].color = blk.color;

}

/* ブロックの落下 */

function isLanded(c, squres, blk) {

/* 着地判定 */

for (var x = 0; x < blk.shape.length; x++) {

for (var y = 0; y < blk.shape[0].length; y++) {

if (blk.shape[x][y] != 0) {

/* 地面と接触 */

if ((blk.y + y) == (c.ysqs - 1)) {

return true;

}

/* 既設ブロックと接触 */

if (squres[blk.x + x][blk.y + y + 1].color != c.color) {

return true;

}

/* Not着地 */

return false;

}

/* GameOverですか? */

function isGameOver(c, squres) {

for (var x = c.xsqs/2 - 2 ; x < c.xsqs/2 + 2; x++) {

if (squres[x][0].color != c.color) {

return true;

}

return false;

}

/* 行削除 */

function eraseLine(c, squres) {

for (var y = 0; y < c.ysqs; y++) {

/* is enable to erase ? */

var flag = true;

for (var x = 0; x < c.xsqs; x++) {

if (squres[x][y].color == c.color) {

flag = false;

break;

}

if(!flag) {

continue;

}

/* do to erase */

for (var x = 0; x < c.xsqs; x++) {

squres[x][y].color = c.color;

}

if (y != 0) {

for (var y1 = y; y1 != 0; y1--) {

for (var x = 0; x < c.xsqs; x++) {

squres[x][y1].color = squres[x][y1-1].color;

}

/* main処理 */

function tetris(ctx, c, squres, blk) {

if (isLanded(c, squres, blk)) {

/* ブロックの着地 */

addBlock2Board(c, squres, blk);

/* 削除処理 */

eraseLine(c, squres);

/* Game Over ? */

if (isGameOver(c,squres)) {

drawTetris(ctx, c, squres, blk);

clearInterval(fallTimer);

} else {

/* 新しいブロックの生成 */

blk = block();

}

} else {

/* 落下 */

blk.y++;

}

/* 盤面の描画 */

drawTetris(ctx, c, squres, blk);

}

window.addEventListener('load', initialize, false);

} )();

</script>

</body>

</html>

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