Creating A Game 2017

Alright! Let’s start with a canvas.

Copy & Paste the code below into your code editor.

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0"/>
<style>
canvas {
    border: 1px solid #d3d3d3;
    background-color: #f1f1f1;
}
</style>
</head>
<body onload="startGame()">
<script>

function startGame() {
    myGameArea.start();
}

var myGameArea = {
    canvas : document.createElement("canvas"),
    start : function() {
        this.canvas.width = 480;
        this.canvas.height = 270;
        this.context = this.canvas.getContext("2d");
        document.body.insertBefore(this.canvas, document.body.childNodes[0]);
    }
}

</script>

<p>We have created a game area! (or at least an empty canvas)</p>

</body>
</html>

Step 2

function component(width, height, color, x, y) {
    this.width = width;
    this.height = height;
    this.x = x;
    this.y = y;    
    ctx = myGameArea.context;
    ctx.fillStyle = color;
    ctx.fillRect(this.x, this.y, this.width, this.height);
}

Step 3

this.interval = setInterval(updateGameArea, 20);




clear : function() {
        this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);
    }




function updateGameArea() {
    myGameArea.clear();
    myGamePiece.update();
}
 this.update = function(){

Test movement

Add this just above the < / script > line

var myUpBtn;

myUpBtn = new component(30, 30, "blue", 50, 10);

        window.addEventListener('mousedown', function (e) {
            myGameArea.x = e.pageX;
            myGameArea.y = e.pageY;
        })
        window.addEventListener('mouseup', function (e) {
            myGameArea.x = false;
            myGameArea.y = false;
        })
        window.addEventListener('touchstart', function (e) {
            myGameArea.x = e.pageX;
            myGameArea.y = e.pageY;
        })
        window.addEventListener('touchend', function (e) {
            myGameArea.x = false;
            myGameArea.y = false;
        })

    this.clicked = function() {
        var myleft = this.x;
        var myright = this.x + (this.width);
        var mytop = this.y;
        var mybottom = this.y + (this.height);
        var clicked = true;
        if ((mybottom < myGameArea.y) || (mytop > myGameArea.y)
         || (myright < myGameArea.x) || (myleft > myGameArea.x)) {
            clicked = false;
        }
        return clicked;
    }

if (myGameArea.x && myGameArea.y) {
        if (myUpBtn.clicked()) {
            myGamePiece.y -= 1;
        }
        if (myDownBtn.clicked()) {
            myGamePiece.y += 1;
        }
        if (myLeftBtn.clicked()) {
            myGamePiece.x += -1;
        }
        if (myRightBtn.clicked()) {
            myGamePiece.x += 1;
        }
    }
    myUpBtn.update();
    myDownBtn.update();
    myLeftBtn.update();
    myRightBtn.update();

This will allow us to test our code out! And experiment with moving components!