如何在javascript游戏中添加播放功能

时间:2016-06-16 11:55:25

标签: javascript html 2d-games

我很难为我的代码添加播放功能而且我不知道我做错了什么。任何帮助????在玩家死于游戏后,我似乎没有更新我的gameArea。

此外,在显示器中使用图像而不是文本后,我的分数不再显示。如何在我的代码中显示图像时添加分数

<!DOCTYPE html>
<html>
<head>


<style>
canvas {
    border:1px solid #d3d3d3;
    background-image: url("http://i.stack.imgur.com/WHu9Z.png");
}
</style>
</head>
<body>
<script>

var myGamePiece;
var myObstacles = [];
var myScore;

function startGame() {
    myGamePiece = new component(40, 40, "http://orig15.deviantart.net/a436/f/2012/101/1/c/mario_sprite_by_flamingdragon5000-d4vt57a.png", 10, 120, "image");
    myGamePiece.gravity = 0.05;
    myScore = new component("30px", "Consolas", "black", 280, 40, "text");
    myGameArea.start();
}

var myGameArea = {
    canvas : document.createElement("canvas"),
    start : function() {
        this.canvas.width = 480;
        this.canvas.height = 350;
        this.context = this.canvas.getContext("2d");
        document.body.insertBefore(this.canvas, document.body.childNodes[0]);
        this.frameNo = 0;
        this.interval = setInterval(updateGameArea, 20);
        },
    clear : function() {
        this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);
    }
}

function component(width, height, color, x, y, type) {
    this.type = type;
    if (type == "image") {
        this.image = new Image();
        this.image.src = color;
    }
    this.score = 0;
    this.width = width;
    this.height = height;
    this.speedX = 0;
    this.speedY = 0;
    this.x = x;
    this.y = y;
    this.gravity = 0;
    this.gravitySpeed = 0;
    this.update = function() {
        ctx = myGameArea.context;
        if (this.type == "image") {
            ctx.drawImage(this.image,
                this.x,
                this.y,
                this.width, this.height);
        } else {
            ctx.fillStyle = color;
            ctx.fillRect(this.x, this.y, this.width, this.height);
        } 
    }
    this.newPos = function() {
        this.gravitySpeed += this.gravity;
        this.x += this.speedX;
        this.y += this.speedY + this.gravitySpeed;
        this.hitBottom();
    }
    this.hitBottom = function() {
        var rockbottom = myGameArea.canvas.height - this.height -23;
        if (this.y > rockbottom) {
            this.y = rockbottom;
            this.gravitySpeed = 0;
        }
    }
    this.crashWith = function(otherobj) {
        var myleft = this.x;
        var myright = this.x + (this.width);
        var mytop = this.y;
        var mybottom = this.y + (this.height);
        var otherleft = otherobj.x;
        var otherright = otherobj.x + (otherobj.width);
        var othertop = otherobj.y;
        var otherbottom = otherobj.y + (otherobj.height);
        var crash = true;
        if ((mybottom < othertop) || (mytop > otherbottom) || (myright < otherleft) || (myleft > otherright)) {
            crash = false;
        }
        return crash;
    }
}

function updateGameArea() {
    var x, height, gap, minHeight, maxHeight, minGap, maxGap;
    for (i = 0; i < myObstacles.length; i += 1) {
        if (myGamePiece.crashWith(myObstacles[i])) {
            return;
        }
    }
    myGameArea.clear();
    myGameArea.frameNo += 1;
    if (myGameArea.frameNo == 1 || everyinterval(150)) {
        x = myGameArea.canvas.width;
        minHeight = 20;
        maxHeight = 200;
        height = Math.floor(Math.random()*(maxHeight-minHeight+1)+minHeight);
        minGap = 90;
        maxGap = 200;
        gap = Math.floor(Math.random()*(maxGap-minGap+1)+minGap);
        myObstacles.push(new component(50, height, "green", x, 0));
        myObstacles.push(new component(50, x - height - gap, "green", x, height + gap));
    }
    for (i = 0; i < myObstacles.length; i += 1) {
        myObstacles[i].x += -1;
        myObstacles[i].update();
    }
    myScore.text="SCORE: " + myGameArea.frameNo;
    myScore.update();
    myGamePiece.newPos();
    myGamePiece.update();
}

function everyinterval(n) {
    if ((myGameArea.frameNo / n) % 1 == 0) {return true;}
    return false;
}

function accelerate(n) {
    myGamePiece.gravity = n;
}

function clickPlayagain() {
     myGameArea.stop(); 

    // myGameArea2.stop();  
    startGame();


}
startGame();
</script>
<br>
<button onmousedown="accelerate(-0.15)" onmouseup="accelerate(0.08)">ACCELERATE</button>
<button id="playagain" onclick="clickPlayagain()">Play again</button>

<p>Use the ACCELERATE button to stay in the air</p>
</body>
</html>

1 个答案:

答案 0 :(得分:2)

希望有所帮助:

<!DOCTYPE html>
<html>
<head>


<style>
canvas {
    border:1px solid #d3d3d3;
    background-image: url("http://i.stack.imgur.com/WHu9Z.png");
}
</style>
</head>
<body>
<script>

var myGamePiece;
var myObstacles = [];
var myScore;
var myGameArea;

function startGame() {
    myGamePiece = new component(40, 40, "http://orig15.deviantart.net/a436/f/2012/101/1/c/mario_sprite_by_flamingdragon5000-d4vt57a.png", 10, 120, "image");
    myGamePiece.gravity = 0.05;
    myScore = new component("30px", "Consolas", "black", 280, 40, "text");
    if(myGameArea){
        document.removeChild(myGameArea.canvas);
    }
    myGameArea = {
        canvas : document.createElement("canvas"),
        start : function() {
            this.canvas.width = 480;
            this.canvas.height = 350;
            this.context = this.canvas.getContext("2d");
            document.body.insertBefore(this.canvas, document.body.childNodes[0]);
            this.frameNo = 0;
            this.interval = setInterval(updateGameArea, 20);
            },
        clear : function() {
            this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);
        }
    }
    myGameArea.start();
}

function reset(){
    myGamePiece = undefined;
    myObstacles = [];
    myScore = "";
}

function component(width, height, color, x, y, type) {
    this.type = type;
    if (type == "image") {
        this.image = new Image();
        this.image.src = color;
    }
    this.score = 0;
    this.width = width;
    this.height = height;
    this.speedX = 0;
    this.speedY = 0;
    this.x = x;
    this.y = y;
    this.gravity = 0;
    this.gravitySpeed = 0;
    this.update = function() {
        ctx = myGameArea.context;
        if (this.type == "image") {
            ctx.drawImage(this.image,
                this.x,
                this.y,
                this.width, this.height);
        }
        if (this.type == "text") {
            ctx.font = this.width + " " + this.height;
            ctx.fillStyle = color;
            ctx.fillText(this.text, this.x, this.y);
        }
        ctx.fillStyle = color;
        ctx.fillRect(this.x, this.y, this.width, this.height);
    }
    this.newPos = function() {
        this.gravitySpeed += this.gravity;
        this.x += this.speedX;
        this.y += this.speedY + this.gravitySpeed;
        this.hitBottom();
    }
    this.hitBottom = function() {
        var rockbottom = myGameArea.canvas.height - this.height -23;
        if (this.y > rockbottom) {
            this.y = rockbottom;
            this.gravitySpeed = 0;
        }
    }
    this.crashWith = function(otherobj) {
        var myleft = this.x;
        var myright = this.x + (this.width);
        var mytop = this.y;
        var mybottom = this.y + (this.height);
        var otherleft = otherobj.x;
        var otherright = otherobj.x + (otherobj.width);
        var othertop = otherobj.y;
        var otherbottom = otherobj.y + (otherobj.height);
        var crash = true;
        if ((mybottom < othertop) || (mytop > otherbottom) || (myright < otherleft) || (myleft > otherright)) {
            crash = false;
        }
        return crash;
    }
}

function updateGameArea() {
    var x, height, gap, minHeight, maxHeight, minGap, maxGap;
    for (i = 0; i < myObstacles.length; i += 1) {
        if (myGamePiece.crashWith(myObstacles[i])) {
            return;
        }
    }
    myGameArea.clear();
    myGameArea.frameNo += 1;
    if (myGameArea.frameNo == 1 || everyinterval(150)) {
        x = myGameArea.canvas.width;
        minHeight = 20;
        maxHeight = 200;
        height = Math.floor(Math.random()*(maxHeight-minHeight+1)+minHeight);
        minGap = 90;
        maxGap = 200;
        gap = Math.floor(Math.random()*(maxGap-minGap+1)+minGap);
        myObstacles.push(new component(50, height, "green", x, 0));
        myObstacles.push(new component(50, x - height - gap, "green", x, height + gap));
    }
    for (i = 0; i < myObstacles.length; i += 1) {
        myObstacles[i].x += -1;
        myObstacles[i].update();
    }
    myScore.text="SCORE: " + myGameArea.frameNo;
    myScore.update();
    myGamePiece.newPos();
    myGamePiece.update();
}

function everyinterval(n) {
    if ((myGameArea.frameNo / n) % 1 == 0) {return true;}
    return false;
}

function accelerate(n) {
    myGamePiece.gravity = n;
}

function clickPlayagain() {
     reset();
     startGame();

}
startGame();
</script>
<br>
<button onmousedown="accelerate(-0.15)" onmouseup="accelerate(0.08)">ACCELERATE</button>
<button id="playagain" onclick="clickPlayagain()">Play again</button>

<p>Use the ACCELERATE button to stay in the air</p>
</body>
</html>