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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              body {
  background-color: #222222;
              // forked from hothukurou's "数学で弾の挙動決める(真上)" http://jsdo.it/hothukurou/6mAp
enchant();  //enchant.jsの初期化

const shotInterval = 15;    //弾の発射間隔
const shotSpeed = 5;    //弾の速さ(1フレームに何px動くか)

const DEG_TO_RAD = (2 * Math.PI) / 360;    //上の度数法をRadに変換する為の数値
const rotateInterval = 30 * DEG_TO_RAD;    //弾の回転移動角度(30度)

window.onload = function () {   //html読み込み完了時に実行する関数
    const game = new Game(400, 400); //width:400px,height:400pxのゲーム画面を設置
    game.fps = 30; //fpsを30に設定
    game.onload = function () { //gameオブジェクトのロード完了時に実行する関数
        const scene = new Scene(); //spriteを貼り付けるsceneを定義
        scene.backgroundColor = "#ffffff";    //sceneの背景を白にする

        const blackRect = new Sprite(16, 16);   //width:16px,height:16pxのSpriteを設置
        blackRect.moveTo(192, 192); //(x,y)=(192,192)に設置
        blackRect.backgroundColor = "#000000";//黒で塗る
        blackRect.time = 0; //フレームカウント用の変数
        blackRect.onenterframe = function () {  //毎フレーム毎に実行する関数
            this.time++;    //フレーム毎にtimeを加算する
            if (this.time % shotInterval == 0) {    //shotIntervalフレーム経ったら弾発射
                const bullet = createBullet(this);  //弾を自分の座標に設置
                scene.addChild(bullet); //sceneに弾を貼り付ける
        scene.addChild(blackRect);  //sceneに黒四角を貼り付ける

        function createBullet(sprite) {
            const bullet = new Sprite(8, 8);   //width:8px,height:8pxのSpriteを設置
            bullet.moveTo(sprite.x, sprite.y);  //発射元の座標に弾を合わせる
            bullet.backgroundColor = "#ff0000"; //赤に設定
            bullet.rad = (sprite.time / shotInterval) * rotateInterval;    //現在の時間から角度を生成
            bullet.onenterframe = function () {
                this.x += Math.cos(this.rad) * shotSpeed;    //移動角度のcosがX軸移動方向
                this.y += Math.sin(this.rad) * shotSpeed;    //移動角度のsinがY軸移動方向
                if (bullet.x <= -30 || bullet.x >= 430 || bullet.y <= -30 || bullet.y >= 430) { //画面外か判定
                    this.parentNode.removeChild(this);  //画面外なら自身を削除する
            return bullet; //上で作成したspriteを返す

    game.start();   //gameオブジェクトを開始する

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