User talk:Bastian: Difference between revisions

Revision as of 14:15, 8 July 2017

<!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>

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

function startGame() {

   myGamePiece = new component(30, 30, "red", 10, 120);
   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 = 270;
       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;
   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 == "text") {
           ctx.font = this.width + " " + this.height;
           ctx.fillStyle = color;
           ctx.fillText(this.text, this.x, this.y);
       } 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;
       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 = 50;
       maxGap = 200;
       gap = Math.floor(Math.random()*(maxGap-minGap+1)+minGap);
       myObstacles.push(new component(10, height, "green", x, 0));
       myObstacles.push(new component(10, 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;

} </script> <br> <button onmousedown="accelerate(-0.2)" onmouseup="accelerate(0.05)">ACCELERATE</button> <p>Use the ACCELERATE button to stay in the air</p> <p>How long can you stay alive?</p> </body> </html>