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Run the next level in our javascript game?

We make a game for our school, it is quite simple, but we cannot understand how to make it run the next level. We currently have a button to load a new page when they finish the level, but with this method it is obviously very easy to trick. We were interested in how we can do this, when the red dot (symbol) reaches the top box, the next level loads. I will post the first level for reference.

   <html>
<head>
<style>
            canvas, img {
            display:block; margin:1em auto; border:1px solid black;
            }
            canvas { 
            background:url(Clouds.png);
            }
        </style>
</head>
<body>
<canvas id="canvas" style="border:1px solid #000"></canvas>
<script>
    (function () {
    var requestAnimationFrame = window.requestAnimationFrame || window.mozRequestAnimationFrame || window.webkitRequestAnimationFrame || window.msRequestAnimationFrame;
    window.requestAnimationFrame = requestAnimationFrame;
})();

var canvas = document.getElementById("canvas"),
    ctx = canvas.getContext("2d"),
    width = 500,
    height = 200,
    player = {
        x: width / 2,
        y: height - 15,
        width: 5,
        height: 5,
        speed: 3,
        velX: 0,
        velY: 0,
        jumping: false,
        grounded: false
    },
    keys = [],
    friction = 0.8,
    gravity = 0.3;

var boxes = [];

// dimensions
boxes.push({
    x: 0,
    y: 0,
    width: 10,
    height: height
});
boxes.push({
    x: 0,
    y: height - 2,
    width: width,
    height: 50
});
boxes.push({
    x: width - 10,
    y: 0,
    width: 50,
    height: height
});

boxes.push({
    x: 120,
    y: 10,
    width: 80,
    height: 80
});
boxes.push({
    x: 170,
    y: 50,
    width: 80,
    height: 80
});
boxes.push({
    x: 220,
    y: 100,
    width: 80,
    height: 80
});
boxes.push({
    x: 270,
    y: 150,
    width: 40,
    height: 40
});

canvas.width = width;
canvas.height = height;

function update() {
    // check keys
    if (keys[38] || keys[32] || keys[87]) {
        // up arrow or space
        if (!player.jumping && player.grounded) {
            player.jumping = true;
            player.grounded = false;
            player.velY = -player.speed * 2;
        }
    }
    if (keys[39] || keys[68]) {
        // right arrow
        if (player.velX < player.speed) {
            player.velX++;
        }
    }
    if (keys[37] || keys[65]) {
        // left arrow
        if (player.velX > -player.speed) {
            player.velX--;
        }
    }

    player.velX *= friction;
    player.velY += gravity;

    ctx.clearRect(0, 0, width, height);
    ctx.fillStyle = "black";
    ctx.beginPath();

    player.grounded = false;
    for (var i = 0; i < boxes.length; i++) {
        ctx.rect(boxes[i].x, boxes[i].y, boxes[i].width, boxes[i].height);

        var dir = colCheck(player, boxes[i]);

        if (dir === "l" || dir === "r") {
            player.velX = 0;
            player.jumping = false;
        } else if (dir === "b") {
            player.grounded = true;
            player.jumping = false;
        } else if (dir === "t") {
            player.velY *= -1;
        }

    }

    if(player.grounded){
         player.velY = 0;
    }

    player.x += player.velX;
    player.y += player.velY;

    ctx.fill();
    ctx.fillStyle = "red";
    ctx.fillRect(player.x, player.y, player.width, player.height);

    requestAnimationFrame(update);
}

function colCheck(shapeA, shapeB) {
    // get the vectors to check against
    var vX = (shapeA.x + (shapeA.width / 2)) - (shapeB.x + (shapeB.width / 2)),
        vY = (shapeA.y + (shapeA.height / 2)) - (shapeB.y + (shapeB.height / 2)),
        // add the half widths and half heights of the objects
        hWidths = (shapeA.width / 2) + (shapeB.width / 2),
        hHeights = (shapeA.height / 2) + (shapeB.height / 2),
        colDir = null;

    // if the x and y vector are less than the half width or half height, they we must be inside the object, causing a collision
    if (Math.abs(vX) < hWidths && Math.abs(vY) < hHeights) {
        // figures out on which side we are colliding (top, bottom, left, or right)
        var oX = hWidths - Math.abs(vX),
            oY = hHeights - Math.abs(vY);
        if (oX >= oY) {
            if (vY > 0) {
                colDir = "t";
                shapeA.y += oY;
            } else {
                colDir = "b";
                shapeA.y -= oY;
            }
        } else {
            if (vX > 0) {
                colDir = "l";
                shapeA.x += oX;
            } else {
                colDir = "r";
                shapeA.x -= oX;
            }
        }
    }
    return colDir;
}

document.body.addEventListener("keydown", function (e) {
    keys[e.keyCode] = true;
});

document.body.addEventListener("keyup", function (e) {
    keys[e.keyCode] = false;
});


window.addEventListener("load", function () {
    update();
});
</script>
<br>
<center>
<input type="button" name="next" value="Click me when finished! No cheating! ;)" onclick="location.href='level2.html';">
</center>
<center>
<input type="button" name="restart" value="Restart" onclick="location.href='javagame.html';">
</center>
</body>
</html>
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1 answer

In your update function, you can add logic that checks if the player is in a position corresponding to your completion state. Then in the conditional set location.href = 'level2.html';

, colCheck , . :

if(playerReachedFinish()) {
  location.href = 'level2.html';
}
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