如何为基本 HTML/JS 游戏创建游戏结束画面？

Question

我一直在根据教程制作一款受 Atari Breakout 启发的游戏。我想知道如何制作一个玩家死亡后会显示的“游戏结束”屏幕。我拥有的代码有一个我创建的名为“DrawDeath()”的变量。我对其进行了编码，以便在您死后显示文本，但由于某种原因它永远不会显示。



var interval = setInterval(draw, 10);
var canvas = document.getElementById("myCanvas");       //Variables for the canvas, ball, paddle, keys, and bricks
var ctx = canvas.getContext("2d");
var ballRadius = 10;
var x = canvas.width / 2;
var y = canvas.height - 30;
var dx = 2;
var dy = -2;
var paddleHeight = 10;
var paddleWidth = 75;
var paddleX = (canvas.width - paddleWidth) / 2;
var rightPressed = false;
var leftPressed = false;
var brickRowCount = 3;
var brickColumnCount = 5;
var brickWidth = 75;
var brickHeight = 20;
var brickPadding = 10;
var brickOffsetTop = 30;
var brickOffsetLeft = 30;
var score = 0;
var bricks = [];
for (var c = 0; c < brickColumnCount; c++) {
    bricks[c] = [];
    for (var r = 0; r < brickRowCount; r++) {
        bricks[c][r] = { x: 0, y: 0, status: 1 };
    }
}

document.addEventListener("keydown", keyDownHandler, false);     //Listening for pressed keys
document.addEventListener("keyup", keyUpHandler, false);

function keyDownHandler(e) {
    if (e.code == "ArrowRight") {       //If key is pressed
        rightPressed = true;
    }
    if (e.code == 'ArrowLeft') {
        leftPressed = true;
    }
    else if (e.code == 'ArrowDown') {
        downPressed = true;
    }
}
function keyUpHandler(e) {
    if (e.code == "ArrowRight") {     //If key is up
        rightPressed = false;
    }
    if (e.code == 'ArrowLeft') {
        leftPressed = false;
    }
    else if (e.code == 'ArrowDown') {
        downPressed = false;
    }
}

function collisionDetection() {
    for (var c = 0; c < brickColumnCount; c++) {
        for (var r = 0; r < brickRowCount; r++) {
            var b = bricks[c][r];
            if (b.status == 1) {
                if (x > b.x && x < b.x + brickWidth && y > b.y && y < b.y + brickHeight) {
                    dy = -dy;
                    b.status = 0;
                    score++;
                    if (score == brickRowCount * brickColumnCount) {
                        drawDeath();
                    }
                }
            }
        }
    }
}

function drawDeath() {
    ctx.font = "32px Courier New";
    ctx.fillStyle = "#000000";
    ctx.fillText("HAHA YU LOOZD (pres doun arouw tu x-it)");
    if (downPressed = true)
        document.location.reload();
        clearInterval(interval);
}

function drawScore() {
    ctx.font = "16px Courier New";
    ctx.fillStyle = "#0E17E8";
    ctx.fillText("Scores is: " + score, 8, 20);
}

function drawBall() {
    ctx.beginPath();
    ctx.arc(x, y, ballRadius, 0, Math.PI * 2);   //Drawing the Ball
    ctx.fillStyle = "#32CD32";
    ctx.fill();
    ctx.closePath();
}

function drawPaddle() {
    ctx.beginPath();
    ctx.rect(paddleX, canvas.height - paddleHeight, paddleWidth, paddleHeight);  //Drawing the Paddle
    ctx.fillStyle = "#0095DD";
    ctx.fill();
    ctx.closePath();
}


function drawBricks() {
    for (var c = 0; c < brickColumnCount; c++) {
        for (var r = 0; r < brickRowCount; r++) {
            if (bricks[c][r].status == 1) {
                var brickX = (c * (brickWidth + brickPadding)) + brickOffsetLeft;
                var brickY = (r * (brickHeight + brickPadding)) + brickOffsetTop;
                bricks[c][r].x = brickX;
                bricks[c][r].y = brickY;
                ctx.beginPath();
                ctx.rect(brickX, brickY, brickWidth, brickHeight);
                if (randomNumber == 1)
                    ctx.fillStyle = "#0095DD";

                if (randomNumber == 2)
                    ctx.fillStyle = "#FF0000";

                if (randomNumber == 3)
                    ctx.fillStyle = "#FF8A00";

                if (randomNumber == 4)
                    ctx.fillStyle = "0100FF";

                ctx.fill()
                ctx.closePath();
            }
        }
    }
}

function draw() {
    ctx.clearRect(0, 0, canvas.width, canvas.height);                 //Clears the screen after each motion
    drawBall();
    drawPaddle();
    drawBricks();
    drawScore();
    collisionDetection();

    //dx = dx + (Math.floor(Math.random() * 5 - 2));
    var cx = dx + (Math.floor(Math.random() * 5 - 2));

    if (x + dx > canvas.width - ballRadius || x + dx < ballRadius) {         //Bounces the ball
        dx = -dx;
    }

    if (y + dy < ballRadius) {
        dy = -dy;
    } else if (y + dy > canvas.height - ballRadius) {
        if (x > paddleX && x < paddleX + paddleWidth) {                 //Paddle Collision features
            dy = -dy;
            dx = cx;
        }
        else {
            Text("HAHA YU LOOZD");
            document.location.reload();                               //Death Detection
            clearInterval(interval);
        }
    }

    if (rightPressed && paddleX < canvas.width - paddleWidth) {             //Paddle Controls
        paddleX += 7;
    }
    else if (leftPressed && paddleX > 0) {
        paddleX -= 7;
    }

    x += dx;
    y += dy;
}

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title>Bad Gramarrs</title>
    <style>
        * {
            padding: 0;
            margin: 0;
        }

        canvas {
            background: #eee;
            display: block;
            margin: 0 auto;
        }


        #main {
            display: none;
        }

        #newGame, #creditBtn, #backBtn {
            text-align: center;
            vertical-align: middle;
            border: 2px solid goldenrod;
            border-radius: 7px;
            background-color: gold;
            color: orangeRed;
            font-size: 32px;
            font-weight: bold;
            font-family: "Courier New";
            width: 5em;
            margin: 5px auto;
        }

        #theHead {
            text-align: center;
            margin: unset;
            color: orange;
            font-size: 2em;
            font-family: "Courier New";
        }

        #credits {
            text-align: center;
            margin: unset;
            color: orange;
            font-size: 2em;
            font-family: "Courier New";
            display: none;
            background-color: inherit;
        }

        #backBtn {
            display: none;
        }
    </style>
</head>
<body>
    <div id="theHead">Bad Gramarrs</div>
    <div id="newGame" onclick="runGame()" onmouseover="this.style.backgroundColor = 'goldenrod'" onmouseout="this.style.backgroundColor = 'gold'">Strt Gaem</div>
    <div id="creditBtn" onmouseover="this.style.backgroundColor = 'goldenrod'" onmouseout="this.style.backgroundColor = 'gold'" onclick="showCredits()">Credets</div>
    <div id="credits">Bad Gramarrs: Maed buy mi</div>
    <div id="backBtn" onmouseover="this.style.backgroundColor = 'goldenrod'" onmouseout="this.style.backgroundColor = 'gold'" onclick="goBack()">Back</div>
    <div id="main">
    <canvas id="myCanvas" width="480" height="320"></canvas>
    </div>
    <script src="atari.js"></script>
   
    <script>
        var runGame = function () {
            document.getElementById("newGame").style.display = "none";
            document.getElementById("theHead").style.display = "none";

            document.getElementById("credits").style.display = "none";
            document.getElementById("main").style.display = "block";
            document.getElementById("creditBtn").style.display = "none";
            randomNumber = Math.floor(Math.random() * 4 + 1);
        };

        var showCredits = function () {
            document.getElementById("theHead").style.display = "none";
            document.getElementById("creditBtn").style.display = "none";
            document.getElementById("newGame").style.display = "none";
            document.getElementById("credits").style.display = "block";
            document.getElementById("backBtn").style.display = "block";
        };

        var goBack = function () {
            document.getElementById("backBtn").style.display = "none";
            document.getElementById("credits").style.display = "none";
            document.getElementById("theHead").style.display = "block";
            document.getElementById("newGame").style.display = "block";
            document.getElementById("creditBtn").style.display = "block";
        };
    </script>

</body>
</html>

Answer 1

您的代码中有一些错误，因此我更正了控制台显示的内容。我还更改了代码以使用 requestAnimationFrame。一旦触发 gameOver 状态，requestAnimationFrame 将停止运行ning 并且 setInterval 将运行 drawDeath 函数。由于缺少 x 和 y 坐标，您的文本游戏也有错误。

此外，我添加了缺少的 downPressed 变量，以便您可以重新启动游戏。

//var interval = setInterval(draw, 10);
let gameOver = false;
var canvas = document.getElementById("myCanvas");       //Variables for the canvas, ball, paddle, keys, and bricks
var ctx = canvas.getContext("2d");
var ballRadius = 10;
var x = canvas.width / 2;
var y = canvas.height - 30;
var dx = 2;
var dy = -2;
var paddleHeight = 10;
var paddleWidth = 75;
var paddleX = (canvas.width - paddleWidth) / 2;
var rightPressed = false;
var leftPressed = false;
var downPressed = false;
var brickRowCount = 3;
var brickColumnCount = 5;
var brickWidth = 75;
var brickHeight = 20;
var brickPadding = 10;
var brickOffsetTop = 30;
var brickOffsetLeft = 30;
var score = 0;
var bricks = [];
for (var c = 0; c < brickColumnCount; c++) {
    bricks[c] = [];
    for (var r = 0; r < brickRowCount; r++) {
        bricks[c][r] = { x: 0, y: 0, status: 1 };
    }
}

document.addEventListener("keydown", keyDownHandler, false);     //Listening for pressed keys
document.addEventListener("keyup", keyUpHandler, false);

function keyDownHandler(e) {
    if (e.code == "ArrowRight") {       //If key is pressed
        rightPressed = true;
    }
    if (e.code == 'ArrowLeft') {
        leftPressed = true;
    }
    else if (e.code == 'ArrowDown') {
        downPressed = true;
        console.log('down')
    }
}
function keyUpHandler(e) {
    if (e.code == "ArrowRight") {     //If key is up
        rightPressed = false;
    }
    if (e.code == 'ArrowLeft') {
        leftPressed = false;
    }
    else if (e.code == 'ArrowDown') {
        downPressed = false;
    }
}

function collisionDetection() {
    for (var c = 0; c < brickColumnCount; c++) {
        for (var r = 0; r < brickRowCount; r++) {
            var b = bricks[c][r];
            if (b.status == 1) {
                if (x > b.x && x < b.x + brickWidth && y > b.y && y < b.y + brickHeight) {
                    dy = -dy;
                    b.status = 0;
                    score++;
                    if (score == brickRowCount * brickColumnCount) {
                        gameOver = true;
                    }
                }
            }
        }
    }
}

function drawDeath() {
    ctx.font = "20px Courier New";
    ctx.textAlign = 'center';
    ctx.fillStyle = "#000000";
    ctx.fillText("HAHA YU LOOZD (pres doun arouw tu x-it)", canvas.width/2, canvas.height/2);
    if (downPressed == true)
    document.location.reload();
}

function drawScore() {
    ctx.font = "16px Courier New";
    ctx.fillStyle = "#0E17E8";
    ctx.fillText("Scores is: " + score, 8, 20);
}

function drawBall() {
    ctx.beginPath();
    ctx.arc(x, y, ballRadius, 0, Math.PI * 2);   //Drawing the Ball
    ctx.fillStyle = "#32CD32";
    ctx.fill();
    ctx.closePath();
}

function drawPaddle() {
    ctx.beginPath();
    ctx.rect(paddleX, canvas.height - paddleHeight, paddleWidth, paddleHeight);  //Drawing the Paddle
    ctx.fillStyle = "#0095DD";
    ctx.fill();
    ctx.closePath();
}


function drawBricks() {
    let randomNumber;
    for (var c = 0; c < brickColumnCount; c++) {
        for (var r = 0; r < brickRowCount; r++) {
            if (bricks[c][r].status == 1) {
                var brickX = (c * (brickWidth + brickPadding)) + brickOffsetLeft;
                var brickY = (r * (brickHeight + brickPadding)) + brickOffsetTop;
                bricks[c][r].x = brickX;
                bricks[c][r].y = brickY;
                ctx.beginPath();
                ctx.rect(brickX, brickY, brickWidth, brickHeight);
                if (randomNumber == 1)
                    ctx.fillStyle = "#0095DD";

                if (randomNumber == 2)
                    ctx.fillStyle = "#FF0000";

                if (randomNumber == 3)
                    ctx.fillStyle = "#FF8A00";

                if (randomNumber == 4)
                    ctx.fillStyle = "0100FF";

                ctx.fill()
                ctx.closePath();
            }
        }
    }
}

function draw() {
    ctx.clearRect(0, 0, canvas.width, canvas.height);                 //Clears the screen after each motion
    drawBall();
    drawPaddle();
    drawBricks();
    drawScore();
    collisionDetection();

    //dx = dx + (Math.floor(Math.random() * 5 - 2));
    var cx = dx + (Math.floor(Math.random() * 5 - 2));

    if (x + dx > canvas.width - ballRadius || x + dx < ballRadius) {         //Bounces the ball
        dx = -dx;
    }

    if (y + dy < ballRadius) {
        dy = -dy;
    } else if (y + dy > canvas.height - ballRadius) {
        if (x > paddleX && x < paddleX + paddleWidth) {                 //Paddle Collision features
            dy = -dy;
            dx = cx;
        }
        else {
            gameOver = true;
            setInterval(drawDeath, 10) //Death Detecti 
        }
    }

    if (rightPressed && paddleX < canvas.width - paddleWidth) {             //Paddle Controls
        paddleX += 7;
    }
    else if (leftPressed && paddleX > 0) {
        paddleX -= 7;
    }

    x += dx;
    y += dy;

    if (!gameOver) requestAnimationFrame(draw)
    
}

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8" />
    <title>Bad Gramarrs</title>
    <style>
        * {
            padding: 0;
            margin: 0;
        }

        canvas {
            background: #eee;
            display: block;
            margin: 0 auto;
        }


        #main {
            display: none;
        }

        #newGame, #creditBtn, #backBtn {
            text-align: center;
            vertical-align: middle;
            border: 2px solid goldenrod;
            border-radius: 7px;
            background-color: gold;
            color: orangeRed;
            font-size: 32px;
            font-weight: bold;
            font-family: "Courier New";
            width: 5em;
            margin: 5px auto;
        }

        #theHead {
            text-align: center;
            margin: unset;
            color: orange;
            font-size: 2em;
            font-family: "Courier New";
        }

        #credits {
            text-align: center;
            margin: unset;
            color: orange;
            font-size: 2em;
            font-family: "Courier New";
            display: none;
            background-color: inherit;
        }

        #backBtn {
            display: none;
        }
    </style>
</head>
<body>
    <div id="theHead">Bad Gramarrs</div>
    <div id="newGame" onclick="runGame()" onmouseover="this.style.backgroundColor = 'goldenrod'" onmouseout="this.style.backgroundColor = 'gold'">Strt Gaem</div>
    <div id="creditBtn" onmouseover="this.style.backgroundColor = 'goldenrod'" onmouseout="this.style.backgroundColor = 'gold'" onclick="showCredits()">Credets</div>
    <div id="credits">Bad Gramarrs: Maed buy mi</div>
    <div id="backBtn" onmouseover="this.style.backgroundColor = 'goldenrod'" onmouseout="this.style.backgroundColor = 'gold'" onclick="goBack()">Back</div>
    <div id="main">
    <canvas id="myCanvas" width="480" height="320"></canvas>
    </div>
    <script src="atari.js"></script>
   
    <script>
        var runGame = function () {
            document.getElementById("newGame").style.display = "none";
            document.getElementById("theHead").style.display = "none";

            document.getElementById("credits").style.display = "none";
            document.getElementById("main").style.display = "block";
            document.getElementById("creditBtn").style.display = "none";
            randomNumber = Math.floor(Math.random() * 4 + 1);
            draw();
        };

        var showCredits = function () {
            document.getElementById("theHead").style.display = "none";
            document.getElementById("creditBtn").style.display = "none";
            document.getElementById("newGame").style.display = "none";
            document.getElementById("credits").style.display = "block";
            document.getElementById("backBtn").style.display = "block";
        };

        var goBack = function () {
            document.getElementById("backBtn").style.display = "none";
            document.getElementById("credits").style.display = "none";
            document.getElementById("theHead").style.display = "block";
            document.getElementById("newGame").style.display = "block";
            document.getElementById("creditBtn").style.display = "block";
        };
    </script>

</body>
</html>

如何为基本 HTML/JS 游戏创建游戏结束画面？

How to create a game over screen for a basic HTML/JS game?

html

javascript

canvas