Javascript refusing to work? - javascript

Well I am coding a little game with js using a HTML5 canvas. I got the canvas and the tag in a html file and the javascript in a seperate file called java.js.
I got some alerts at some moment in the script to find out if it runs when I load the html into my browser. Problem is it does not show any of these and the javascript doesnt load.
The weirdest is what firebug does: Under "HTML" it shows me the full script when I click the tag, but under "Script" it tells me there is no javascript on the page.
Help?
my html:
<body><canvas id="canvas" width="1000px" height="500px" style="border:1px solid #c3c3c3;">text</canvas>
<script type="text/javascript" src="java.js">
</script></body>
When I put the script tag in the head:
<head><script type="text/javascript" src="java.js">
</script></head>
<body><canvas id="canvas" width="1000px" height="500px" style="border:1px solid #c3c3c3;">text</canvas>
</body>
my js:
alert('define');
var scrollx=0,
scrolly=0,
keyID=0,
global = {};
global.players=[];
global.playermap=[];
var c=document.getElementById("canvas"),
ctx=c.getContext('2d');
alert('init');
function pony (x,y, hspd, vspd) {
alert("pony created!");
this.x = x;
this.y = y;
this.vsp = vspd;
this.hspd = hspd;
this.image = new Image();
this.image.src = "alien.png";
this.framenumber = 11;
this.frameactual = 1;
this.framespeed=0.8;
this.frametime =50;
this.framewidth = this.image.width / this.framenumber;
this.frameheight = this.image.height;
this.colorbody="#000000";
//
this.nextframe = function() {
this.frameactual=this.frameactual+this.framespeed;
if (Math.round(this.frameactual)>this.framenumber){this.frameactual=1;}
this.draw();
};
//
this.draw = function() {
this.frame=Math.round(this.frameactual);
ctx.drawImage(this.image,(this.frame-1)*this.framewidth,0,this.framewidth,this.image.height,this.x-scrollx-(this.framewidth/2),this.y-scrolly-(this.image.height/2),this.framewidth,this.image.height);
};
//
//var _this=this;
//this.frametimer=setInterval(function(){_this.nextframe();},this.frametime);
alert("time set");
}
//
function setpos_player(id,x,y,hspd,vspd){
alert("this");
if (typeof(global.playermap[id])=="undefined"){
global.players.push(new pony (x,y, hspd, vspd));
global.playermap[id]=global.players.length;}
else{
global.players[global.playermap[id]].x=x;
global.players[global.playermap[id]].y=y;
global.players[global.playermap[id]].hspd=hspd;
global.players[global.playermap[id]].vspd=vspd;}
}
//
function clear(){
ctx.fillStyle = "#FFFFFF";
ctx.beginPath();
ctx.rect(0,0,1000,1000);
ctx.closePath();
ctx.fill();}
document.onkeypress = KeyCheck;
document.onkeydown = KeyCheck;
document.onkeyup = KeyRelease;
function KeyCheck(e)
{
keyID = (window.event) ? event.keyCode : e.keyCode;
}
function KeyRelease(e)
{keyID=0;}
//
function step(){
clear();
for (var i = 0; i < global.players.length; i++) {
_this=global.players[i];
_this.y+=_this.vspd;
_this.nextframe();
//Do something
}
//global.players[1].nextframe();
timer=setTimeout(function(){step();},80);
}
setpos_player(1,200,200,0,1);
var timer=setTimeout(function(){step();},80);

Seems you have an error here:
if (typeof(global.playermap[id])="undefined"){
should be
if (typeof(global.playermap[id])=="undefined"){
also, try replacing all alert calls to console.log and then check out the console for errs

declare script before you use it in the html
you can put that script in head of the page like this
<head>
<script type='text/javascript' src='java.js'></script>
</head>
try it once and replay here

if (typeof(global.playermap[id])="undefined"){
to
if (typeof global.playermap[id] == "undefined"){

Try to put the right directory path for the .js file. For example it may be /java.js or "/scripts/java.js".
The indication if javascript is loaded will be if your alert pops up.
Also, you should know that script tags, with external .js should be added in HEAD section.

Related

HTML5/Javascript Image loading method & passing to variable

I have some code for loading images.
var assets = {
total:0,
success:0,
error:0
};
var stillLoading = true;
var img = {};
function LoadImage(name, path){
var toLoad = new Image();
toLoad.src = path;
assets.total++;
toLoad.addEventListener("load", function(){
assets.success++;
console.log(name + " loaded.");
img[name] = toLoad;
}, false);
toLoad.addEventListener("error", function(){
assets.error++;
}, false);
};
function Loading(){
if (assets.success == assets.total){
if (stillLoading){
console.log("All assets loaded. Starting game.");
};
stillLoading = false;
return false;
}else{
stillLoading = true;
return true;
};
};
May still be inefficient, and ugly since I'm new to practicing javascript, open to suggestions. It loads the image and tells the main program when all the assets have finished loading through the function Loading(), and then adds the image to the object img.
I've been using this for a while now for my images, and it works.
For example, if I did.
LoadImage("Car", "imageOfCar.png");
ctx.drawImage(img.Car, 0, 0);
this would draw the image just fine to the canvas.
However, when I assign another variable the image, which for various reasons I want to do, such as assigning images to objects. e.g.
var secondCar = img.Car
then try to draw it.
ctx.drawImage(secondCar, 0, 0);
I get this error.
Uncaught TypeError: Failed to execute 'drawImage' on 'CanvasRenderingContext2D': The provided value is not of type '(HTMLImageElement or HTMLVideoElement or HTMLCanvasElement or ImageBitmap)'
If it works for the initial variable, it should act the same way towards another variable that has just been assigned the exact same thing. So why is it am I getting this error?
If I was to load the image the typical way that doesn't check if it's finished loading.
img.Car = new Image();
img.Car.src = "imageOfCar.png";
secondCar = img.Car;
ctx.drawImage(secondCar);
This would work.
The behaviour here is a bit confusing, could someone explain to me what is happening, and perhaps suggest a way to fix it?
EDIT: Just to clarify.
This is the html file, called index.html.
<!DOCTYPE html>
<head>
<title>HTML5 Game Base</title>
<link rel = "stylesheet" type = "text/css" href = "styles.css">
</head>
<body>
<canvas id="screen" width="270" height="480" style="border:1px solid #000000;"></canvas>
<script src = "script.js"></script>
</body>
</html>
The canvas is set up as screen. All the javascript code I've displayed above takes place within script.js which is called in index.html.
This is how screen is called within the script.js.
var canvas = document.getElementById("screen");
var ctx = canvas.getContext("2d");
This is what ctx.drawImage() is referencing.
I realize this won't be the most helpful answer, but I tinkered around with your code a little. This is what I used:
<!DOCTYPE html>
<head>
<title>HTML5 Game Base</title>
</head>
<body>
<canvas id="screen" width="270" height="480" style="border:1px solid #000000;"></canvas>
<script>
var stillLoading = true;
var img = {};
var canvas = document.getElementById("screen");
var ctx = canvas.getContext("2d");
assets = {};
assets.total = 0;
function LoadImage(name, path){
var toLoad = new Image();
toLoad.src = path;
assets.total++;
toLoad.addEventListener("load", function(){
//assets.success++;
console.log(name + " loaded.");
img[name] = toLoad;
}, false);
toLoad.addEventListener("error", function(){
assets.error++;
}, false);
}
</script>
</body>
</html>
Then in Chrome's console I typed
LoadImage("Car", "map.png");
LoadImage("un", "Untitled.png");
ctx.drawImage(img.Car, 0, 0);
ctx.drawImage(img.un, 0, 0);
and get the expected result of images loading in the canvas. Even when assigning one of the img images to a new variable, this works as expected.
var second = img.Car
ctx.drawImage(second, 0, 0)
It appears everything is working fine when run manually, so my guess would be timing. When are you running these commands? Are they in the js file or from the console?
It would appear your LoadImage function is fine. Sorry this is not super helpful, but hopefully will help you rule out where not to look for the problem.
One approach could be to utilize Promise , as load event of new Image is asynchronous secondCar could be undefined when used as parameter within setInterval, e.g., load event of img may not be complete when var secondCar = img.Car applied after call to LoadImage; also added variable reference for setInterval for ability to call clearInterval() if needed
var canvas = document.getElementById("screen");
var ctx = canvas.getContext("2d");
var interval = null;
var assets = {
total: 0,
success: 0,
error: 0
};
var stillLoading = true;
var img = {};
function LoadImage(name, path) {
return new Promise(function(resolve, reject) {
var toLoad = new Image();
assets.total++;
toLoad.addEventListener("load", function() {
assets.success++;
console.log(name + " loaded.");
img[name] = toLoad;
// resolve `img` , `assets` object
resolve([img, assets])
}, false);
toLoad.addEventListener("error", function() {
assets.error++;
reject(assets)
}, false);
toLoad.src = path;
})
};
function Loading() {
if (assets.success == assets.total) {
if (stillLoading) {
console.log("All assets loaded. Starting game.");
};
stillLoading = false;
return false;
} else {
stillLoading = true;
return true;
};
};
var promise = LoadImage("Car", "http://pngimg.com/upload/audi_PNG1736.png");
promise.then(function(data) {
// `data` : array containing `img` , `assets` objects
console.log(data);
var secondCar = data[0].Car;
interval = setInterval(function() {
if (!(Loading())) {
ctx.drawImage(secondCar, 0, 0);
};
}, 1000 / 60);
});
<canvas id="screen" width="1000" height="700" style="border:1px solid #000000;"></canvas>
Solved. Turns out it was a timing issue. In the example I gave, when secondCar is assigned img.Car, img.Car had not yet loaded.
Instead I created a new function called Initialise(), and called it from within Loading(). So from now on I would just have to initialise all my variables that may require images from within Initialise(). This way, variables can only be assigned images after they've loaded.
New Code:
var canvas = document.getElementById("screen");
var ctx = canvas.getContext("2d");
var assets = {
total:0,
success:0,
error:0
};
var stillLoading = true;
var img = {};
function LoadImage(name, path){
var toLoad = new Image();
toLoad.src = path;
assets.total++;
toLoad.addEventListener("load", function(){
assets.success++;
console.log(name + " loaded.");
img[name] = toLoad;
}, false);
toLoad.addEventListener("error", function(){
assets.error++;
}, false);
};
function Loading(){
if (assets.success == assets.total){
if (stillLoading){
console.log("All assets loaded. Starting game.");
Initialise();
};
stillLoading = false;
return false;
}else{
stillLoading = true;
return true;
};
};
LoadImage("Car", "http://pngimg.com/upload/audi_PNG1736.png");
function Initialise(){
window.secondCar = img.Car;
};
setInterval(function(){
if (!(Loading())) ctx.drawImage(secondCar, 0, 0);
}, 1000/60);
Works now, thanks for the help although I ended up solving it myself. I would still appreciate any tips on how to improve it. Or knowing that I'm new to javascript, any nitpicks to help me conform to javascript conventions.

Why does my HTML and JS not work?

I can't get this to work on my public webpage. I've made sure all permissions on files are correct, but when I go to the site, it just shows a blank page. It's supposed to have a matrix-like effect. I edited it through Codepen.io, but when I transfer it over to actual files and upload them, nothing works.
HTML:
<html><head>
<script src="(link the js file attached that is in the directory of my webpage)" type="text/javascript"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
<meta charset="utf-8">
<title>Matrix</title>
</head>
<body>
<div align="center">
<canvas id="canvas" width="500" height="500">
</canvas><br/><br/>
</div>
</body>
</html>
JavaScript:
//this is my matrix.js file
$(document).ready(function(){
var s=window.screen;
var width = canvas.width=s.width;
var height = canvas.height;
var inLink = false;
var yPositions = Array(300).join(0).split('');
var context=canvas.getContext('2d');
var draw = function () {
context.fillStyle='rgba(0,0,0,.05)';
context.fillRect(0,0,width,height);
context.fillStyle='#0F0';
canvas.addEventListener("click", on_click, false);
canvas.addEventListener("mousemove", on_mousemove, false);
context.fillText(linkText,10,50);
context.font = '12pt Georgia';
yPositions.map(function(y, index){
text = String.fromCharCode(1e3+Math.random()*33);//determines characters randomly from this specific font
x = (index * 10)+10;
canvas.getContext('2d').fillText(text, x, y);
if(y > 100 + Math.random()*1e4)
{
yPositions[index]=0;
}
else
{
yPositions[index] = y + 10;
}
});
};
RunMatrix();
function RunMatrix()
{
if(typeof Game_Interval != "undefined") clearInterval(Game_Interval);
Game_Interval = setInterval(draw, 33);
}
})
You have to include your javascript files after the libraries they depend upon
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"
type="text/javascript"></script>
<script src="(link the js file attached that is in the directory of my webpage)" type="text/javascript"></script>
Also, consider using a newer version of jQuery
try adding...
var canvas = document.getElementById('canvas');
at the start of your $(document).ready function...
$(document).ready(function(){
var canvas = document.getElementById('canvas');
....
basically you are referencing 'canvas', which doesn't appear to exist yet..
also make sure you're including jquery before any libraries or scripts that attempt to use it!

Optimizing performance of a javascript image animation

I've got a question in regards to javascript and dynamically displaying images to
form an animation.
The pictures I have are around 1360x768 in size and quite big despite being .png pics.
I've come up with a code for switching out the pics dynamically, but even run on a local
webserver it is too slow (thus sometimes I see the pic being built).
So my question is: is there a better way to do this than dynamically switching out
the "src" part of the image tag, or is there something else that could be done in combination with that, to make sure that the user doesn't have any strange phenomenons
on the client?
<script>
var title_index = 0;
function display_title()
{
document.getElementById('picture').src=
"pics/title_" + title_index + '.png';
if (title_index < 100) {
title_index = title_index + 5;
setTimeout(display_title,3000);
}
}
</script>
<body onload="setTimeout(display_image,3000)">
<image id="picture" src="pic/title_0.png"/>
</body>
Thanks.
I've had this problem too, even when preloading the images into the cache,
Google's The Hobbit experiment does something interesting. They do low resolution while animating and switch it for a hiresolution if you "pause" (stop scolling in the case of The Hobbit experiment). They also use the HTML5 canvas tag to smooth out the animation.
Here's their blog post about their method:
http://www.html5rocks.com/en/tutorials/casestudies/hobbit-front-end/
Their end product:
http://middle-earth.thehobbit.com
Edit:
Pre loading example:
<!Doctype html>
<head>
<title>test</title>
</head>
<body>
<canvas id="myCanvas" width="1360" height="768"></canvas>
<script type="text/javascript">
var images = {};
var loadedImages = 0;
var numImages = 0;
var context = '';
function loadImages(sources, callback)
{
// get num of sources
for(var src in sources)
{
numImages++;
}
for(var src in sources)
{
images[src] = new Image();
images[src].onload = function()
{
if(++loadedImages >= numImages)
{
callback(images);
}
};
images[src].src = sources[src];
}
}
var canvas = document.getElementById('myCanvas');
context = canvas.getContext('2d');
var sources =
{
frame0: 'http://piggyandmoo.com/0001.png',
frame1: 'http://piggyandmoo.com/0002.png',
frame2: 'http://piggyandmoo.com/0003.png',
frame3: 'http://piggyandmoo.com/0004.png',
frame4: 'http://piggyandmoo.com/0005.png',
frame5: 'http://piggyandmoo.com/0006.png',
frame5: 'http://piggyandmoo.com/0007.png',
frame5: 'http://piggyandmoo.com/0008.png',
frame5: 'http://piggyandmoo.com/0009.png'
};
var width = 1360;
var height = 768;
var inter = '';
var i = 0;
function next_frame()
{
if(numImages > i)
{
context.drawImage(images['frame' + (i++)], 0, 0);
}
else
{
clearInterval(inter);
}
}
loadImages(sources, function(images)
{
//animate using set_timeout or some such...
inter = setInterval(function()
{
next_frame();
}, 1000);
});
</script>
</body>
Code modified from: www.html5canvastutorials.com/tutorials/html5-canvas-image-loader/
You could overcome this issue by preloading the images on page load. This means that the images would then be stored in memory and immediately available to you. Take a look at the following:
JavaScript Preloading Images
http://perishablepress.com/3-ways-preload-images-css-javascript-ajax/

2 or more async requests in javascript to load image or do anything else

Single request and response model at one time do not utilizes full network/internet bandwidth, thus resulting in low performance. (benchmark is of half speed utilization)
how to make this code use 2 or 3 or more async requests instead of one.(ajax)
or do i need multi threading? and is it possible in javascript?
(this is for making a video out of an ip )
every time the image changes on request. and yes i need to be async with multiple fetch requests (not single as i explained above) or you recomend threads?
<html>
<head> <script language="JavaScript">
// Global vars
img = 'http://pastebin.com/i/t.gif';
timeout = 1000;
next = 0;
function onLoad( ) {
setTimeout( 'reloadImage( )', timeout );
}
// Reloader
function reloadImage( ) {
next = ( new Date( ) ).getTime( ) + timeout;
document.images.dv.src = img + "?" + next;
}
</script>
</head>
<body>
<img src="img" name="dv" onLoad="onLoad( )">
</body>
</html>
and
<html>
<head>
</head>
<body>
<div id="container"></div>
<script language="JavaScript">
var canLoad = true;
var container = document.getElementById("container");
var image = document.createElement("img");
image.onload = function() {
canLoad = true;
console.log("Image reloaded.");
}
var imageUrl = "http://url/snapshot.jpg";
var fps = 2;
container.appendChild(image);
function loadImage() {
if (canLoad) {
canLoad = false;
var str = new Date().getTime();
image.setAttribute("src", imageUrl + "?" + str);
console.log("Reloaded now.");
} else {
console.log("Can't reload now.");
}
}
setInterval(loadImage, fps); // 30 fps
</script>
</body>
</html>
Not actually tested, and I think it'll very likely to cause a "stack overflow" eventually (if you directly implement it), but you may still give it a look:
<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
(function(){
var img="/*url*/";
var interval=50;
var pointer=0;
function showImg(image,idx)
{
if(idx<=pointer) return;
document.body.replaceChild(image,document.getElementsByTagName("img")[0]);
pointer=idx;
preload();
}
function preload()
{
var cache=null,idx=0;;
for(var i=0;i<5;i++)
{
idx=Date.now()+interval*(i+1);
cache=new Image();
cache.onload=(function(ele,idx){return function(){showImg(ele,idx);};})(cache,idx);
cache.src=img+"?"+idx;
}
}
window.onload=function(){
document.getElementsByTagName("img")[0].onload=preload;
document.getElementsByTagName("img")[0].src="/*initial url*/";
};
})();
</script>
</head>
<body>
<img />
</body>
</html>
What it does:
When the initial image loads, preload() is called;
When preload() is called, it creates 5 image cache, and each attach its onload event to showImg();
When showImg() is called, it checks whether the current index is behind current pointer, and if it does, replace the current image with this new one, and call preload();
Back to 2.
If you really going to implement this, increase interval and decrease i<5. Also, a caching/queuing mechanic to check how many images in cache/queue before loading the next queue would be nice.
Also, notice that I didn't use getElementById to get the image, because there will be no stable ID.

Getting IE8 compatibility with EaselJS and ExplorerCanvas

I am using EaselJS and want to allow for backwards compatibility with ExplorerCanvas.
This should be possible using the following code (see here):
createjs.createCanvas = function () { ... return canvas implementation here ... }
However, If I put an alert in this function and run the code, the function is never run.
How do I go about getting this to work?
Edit:
Here is a simplified example of the code I am using:
<!DOCTYPE html>
<html lang='en'>
<head>
<meta charset='utf-8' />
<script src='/Scripts/jquery-1.7.1.js'></script>
<script src="/Scripts/excanvas/excanvas.compiled.js"></script>
<script src="/Scripts/easeljs/lib/easeljs-0.5.0.min.js"></script>
<script src='/Scripts/core/jquery.mousewheel.js'></script>
<style>
canvas
{
border: 1px solid #ccc;
}
</style>
<script type='text/javascript'>
$(document).ready(function () {
// Variables
var img;
var stage;
var bmp;
// Bindings
$('#load').click(function () { initialize() }); // DELETE
// Functions
function initialize() {
img = new Image();
img.onload = imageLoadedEvent;
img.src = '/Scripts/viewer/June.jpg';
}
function imageLoadedEvent() {
var canvasElement = generateContext('testCanvas', 400, 400);
stage = new createjs.Stage('testCanvas');
bmp = new createjs.Bitmap(img);
stage.autoClear = true;
stage.addChild(bmp);
stage.update();
}
function generateContext(canvasID, width, height) {
var canvasElement = document.createElement('canvas');
if (typeof (G_vmlCanvasManager) != 'undefined')
canvasElement = G_vmlCanvasManager.initElement(canvasElement);
canvasElement.setAttribute("width", width);
canvasElement.setAttribute("height", height);
canvasElement.setAttribute("id", canvasID);
document.getElementById('viewer').appendChild(canvasElement);
}
});
</script>
</head>
<body>
<div id='viewer'>
<button id='load'>load</button>
</div>
</body>
</html>
This example will run in Chrome and IE9 as a native canvas element is created and used. However in IE8 it fails.
I ran across this issue as well, trying to get ExCanvas to play nice with EaselJS. Here is how I got it working. Hope this helps with your image issue.
Get the source code for EaselJS : https://github.com/gskinner/EaselJS.git. This will get all the javascript files separated out into their own parts.
Copy all those files over to a "easel" folder in your project directory.
The order in which the files are loaded is important, so see below on how to do it.
EaselJS has an option to override the createCanvas method, which is required to use ExCanvas with it. This happens after loading the SpriteSheet.js file, and BEFORE loading Graphics.js, DisplayObject.js, Container.js, etc. In the code below, I used jQuery to load the rest of the js files that easelJs needed. This all happens in the $(document).ready() function.
If done correctly, you should see a 700 x 700 canvas with a red line from top left to bottom right in IE (tested in 8).
head>
<!--
Load ExCanvas first, and jquery
-->
<script type='text/javascript' src='./javascript/excanvas.js'></script>
<script type='text/javascript' src='./javascript/jquery-1.8.2.min.js'></script>
<!--
Have to load Easel js files in a certain order, and override the createCanvas
function in order for it to work in < IE9.
-->
<script type='text/javascript' src='./javascript/easel/UID.js'></script>
<script type='text/javascript' src='./javascript/easel/Ticker.js'></script>
<script type='text/javascript' src='./javascript/easel/EventDispatcher.js'></script>
<script type='text/javascript' src='./javascript/easel/MouseEvent.js'></script>
<script type='text/javascript' src='./javascript/easel/Matrix2D.js'></script>
<script type='text/javascript' src='./javascript/easel/Point.js'></script>
<script type='text/javascript' src='./javascript/easel/Rectangle.js'></script>
<script type='text/javascript' src='./javascript/easel/Shadow.js'></script>
<script type='text/javascript' src='./javascript/easel/SpriteSheet.js'></script>
<script type='text/javascript'>
var canvas, stage;
createjs.createCanvas = function () { return getCanvas(); };
function getCanvas() {
// This is needed, otherwise it will keep adding canvases, but it only use the last one it creates.
canvas = document.getElementById("myCanvas");
if (canvas != null) {
document.getElementById("container").removeChild(canvas);
}
canvas = document.createElement("canvas");
document.getElementById("container").appendChild(canvas);
if (typeof (G_vmlCanvasManager) != 'undefined') {
canvas = G_vmlCanvasManager.initElement(canvas);
canvas.setAttribute("height", "700");
canvas.setAttribute("width", "700");
canvas.setAttribute("style", "height:700px; width:700px;");
canvas.setAttribute("id", "myCanvas");
}
return canvas;
}
</script>
<script type="text/javascript">
$(document).ready(function () {
loadOtherScripts();
stage = new createjs.Stage(canvas);
// Draw a red line from top left to bottom right
var line = new createjs.Shape();
line.graphics.clear();
line.graphics.setStrokeStyle(2);
line.graphics.beginStroke("#FF0000");
line.graphics.moveTo(0, 0);
line.graphics.lineTo(700, 700);
stage.addChild(line);
stage.update();
});
function loadOtherScripts() {
var jsAr = new Array(13);
jsAr[0] = './javascript/easel/Graphics.js';
jsAr[1] = './javascript/easel/DisplayObject.js';
jsAr[2] = './javascript/easel/Container.js';
jsAr[3] = './javascript/easel/Stage.js';
jsAr[4] = './javascript/easel/Bitmap.js';
jsAr[5] = './javascript/easel/BitmapAnimation.js';
jsAr[6] = './javascript/easel/Shape.js';
jsAr[7] = './javascript/easel/Text.js';
jsAr[8] = './javascript/easel/SpriteSheetUtils.js';
jsAr[9] = './javascript/easel/SpriteSheetBuilder.js';
jsAr[10] = './javascript/easel/DOMElement.js';
jsAr[11] = './javascript/easel/Filter.js';
jsAr[12] = './javascript/easel/Touch.js';
for (var i = 0; i < jsAr.length; i++) {
var js = jsAr[i];
$.ajax({
async: false,
type: "GET",
url: js,
data: null,
dataType: 'script'
});
}
}
</head>
<body>
<div id="container"></div>
</body>
</html>
You should instantiate the quasi canvas element by making reference to the original canvas source as provided on the project page example:
<head>
<!--[if lt IE 9]><script src="excanvas.js"></script><![endif]-->
</head>
var el = document.createElement('canvas');
G_vmlCanvasManager.initElement(el);
var ctx = el.getContext('2d');
EDIT:
After further investigation i came to the following conclusions!
There are multiple reasons for not being able to include the image into the canvas:
1st probably there is a bug in the excanvas code for not being able to mimic the native canvas features. I used with more success the modified sancha code, which you can obtain here: http://dev.sencha.com/playpen/tm/excanvas-patch/excanvas-modified.js. See live example here: http://jsfiddle.net/aDHKm/ (try it on IE).
2nd before Easeljs initialize the core objects and classes first is searching for the canvas element existence. Because IE < 9 doesn't have implemented the canvas it's obvious that easeljs core graphics API's can not be instantiated. I think these are the two main reasons that your code is not working.
My suggestion is to try to remake the code without the easeljs. I made a fiddle with the necessary modification to show you how can be done without easeljs: http://jsfiddle.net/xdXrw/. I don't know if it's absolute imperative for you to use easeljs, but certainly it has some limitations in terms of IE8 hacked canvas.

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