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| − | <html>
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| − | <head>
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| − | <meta name="viewport" content="width=device-width, initial-scale=1.0"/>
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| − | <style>
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| − | canvas {
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| − | border:1px solid #d3d3d3;
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| − | background-color: #f1f1f1;
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| − | }
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| − | </style>
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| − | </head>
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| − | <body onload="startGame()">
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| − | <script>
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| − | var myGamePiece;
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| − | var myObstacles = [];
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| − | var myScore;
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| − |
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| − | function startGame() {
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| − | myGamePiece = new component(30, 30, "red", 10, 120);
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| − | myGamePiece.gravity = 0.05;
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| − | myScore = new component("30px", "Consolas", "black", 280, 40, "text");
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| − | myGameArea.start();
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| − | }
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| − |
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| − | var myGameArea = {
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| − | canvas : document.createElement("canvas"),
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| − | start : function() {
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| − | this.canvas.width = 480;
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| − | this.canvas.height = 270;
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| − | this.context = this.canvas.getContext("2d");
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| − | document.body.insertBefore(this.canvas, document.body.childNodes[0]);
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| − | this.frameNo = 0;
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| − | this.interval = setInterval(updateGameArea, 20);
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| − | },
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| − | clear : function() {
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| − | this.context.clearRect(0, 0, this.canvas.width, this.canvas.height);
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| − | }
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| − | }
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| − |
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| − | function component(width, height, color, x, y, type) {
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| − | this.type = type;
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| − | this.score = 0;
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| − | this.width = width;
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| − | this.height = height;
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| − | this.speedX = 0;
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| − | this.speedY = 0;
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| − | this.x = x;
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| − | this.y = y;
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| − | this.gravity = 0;
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| − | this.gravitySpeed = 0;
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| − | this.update = function() {
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| − | ctx = myGameArea.context;
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| − | if (this.type == "text") {
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| − | ctx.font = this.width + " " + this.height;
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| − | ctx.fillStyle = color;
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| − | ctx.fillText(this.text, this.x, this.y);
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| − | } else {
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| − | ctx.fillStyle = color;
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| − | ctx.fillRect(this.x, this.y, this.width, this.height);
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| − | }
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| − | }
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| − | this.newPos = function() {
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| − | this.gravitySpeed += this.gravity;
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| − | this.x += this.speedX;
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| − | this.y += this.speedY + this.gravitySpeed;
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| − | this.hitBottom();
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| − | }
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| − | this.hitBottom = function() {
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| − | var rockbottom = myGameArea.canvas.height - this.height;
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| − | if (this.y > rockbottom) {
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| − | this.y = rockbottom;
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| − | this.gravitySpeed = 0;
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| − | }
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| − | }
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| − | this.crashWith = function(otherobj) {
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| − | var myleft = this.x;
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| − | var myright = this.x + (this.width);
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| − | var mytop = this.y;
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| − | var mybottom = this.y + (this.height);
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| − | var otherleft = otherobj.x;
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| − | var otherright = otherobj.x + (otherobj.width);
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| − | var othertop = otherobj.y;
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| − | var otherbottom = otherobj.y + (otherobj.height);
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| − | var crash = true;
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| − | if ((mybottom < othertop) || (mytop > otherbottom) || (myright < otherleft) || (myleft > otherright)) {
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| − | crash = false;
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| − | }
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| − | return crash;
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| − | }
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| − | }
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| − |
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| − | function updateGameArea() {
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| − | var x, height, gap, minHeight, maxHeight, minGap, maxGap;
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| − | for (i = 0; i < myObstacles.length; i += 1) {
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| − | if (myGamePiece.crashWith(myObstacles[i])) {
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| − | return;
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| − | }
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| − | }
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| − | myGameArea.clear();
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| − | myGameArea.frameNo += 1;
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| − | if (myGameArea.frameNo == 1 || everyinterval(150)) {
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| − | x = myGameArea.canvas.width;
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| − | minHeight = 20;
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| − | maxHeight = 200;
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| − | height = Math.floor(Math.random()*(maxHeight-minHeight+1)+minHeight);
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| − | minGap = 50;
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| − | maxGap = 200;
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| − | gap = Math.floor(Math.random()*(maxGap-minGap+1)+minGap);
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| − | myObstacles.push(new component(10, height, "green", x, 0));
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| − | myObstacles.push(new component(10, x - height - gap, "green", x, height + gap));
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| − | }
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| − | for (i = 0; i < myObstacles.length; i += 1) {
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| − | myObstacles[i].x += -1;
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| − | myObstacles[i].update();
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| − | }
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| − | myScore.text="SCORE: " + myGameArea.frameNo;
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| − | myScore.update();
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| − | myGamePiece.newPos();
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| − | myGamePiece.update();
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| − | }
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| − |
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| − | function everyinterval(n) {
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| − | if ((myGameArea.frameNo / n) % 1 == 0) {return true;}
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| − | return false;
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| − | }
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| − |
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| − | function accelerate(n) {
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| − | myGamePiece.gravity = n;
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| − | }
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| − | </script>
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| − | <br>
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| − | <button onmousedown="accelerate(-0.2)" onmouseup="accelerate(0.05)">ACCELERATE</button>
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| − | <p>Use the ACCELERATE button to stay in the air</p>
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| − | <p>How long can you stay alive?</p>
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| − | </body>
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| − | </html>
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