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PIXI.js AnimatedSprite lag on first play

I need some help understanding what the best practice is for creating a PIXI.extras.AnimatedSprite from spritesheet(s). I am currently loading 3 medium-sized spritesheets for 1 animation, created by TexturePacker, I collect all the frames and then play. However the first time playing the animation is very unsmooth, and almost jumps immediately to the end, from then on it plays really smooth. I have read a bit and I can see 2 possible causes. 1) The lag might be caused by the time taken to upload the textures to the GPU. There is a PIXI plugin called prepare renderer.plugins.prepare.upload which should enable me to upload them before playing and possibly smoothen out the initial loop. 2) Having an AnimatedSprite build from more than one texture/image is not ideal and could be the cause.
Question 1: Should I use the PIXI Prepare plugin, will this help, and if so how do I actually use it. Documentation for it is incredibly limited.
Question 2: Is having frames across multiple textures a bad idea, could it be the cause & why?
A summarised example of what I am doing:
function loadSpriteSheet(callback){
let loader = new PIXI.loaders.Loader()
loader.add('http://mysite.fake/sprite1.json')
loader.add('http://mysite.fake/sprite2.json')
loader.add('http://mysite.fake/sprite3.json')
loader.once('complete', callback)
loader.load()
}
loadSpriteSheet(function(resource){
// helper function to get all the frames from multiple textures
let frameArray = getFrameFromResource(resource)
let animSprite = new PIXI.extras.AnimatedSprite(frameArray)
stage.addChild(animSprite)
animSprite.play()
})

Question 1
So I have found a solution, possibly not the solution but it works well for me. The prepare plugin was the right solution but never worked. WebGL needs the entire texture(s) uploaded not the frames. The way textures are uploaded to the GPU is via renderer.bindTexture(texture). When the PIXI loader receives a sprite atlas url e.g. my_sprites.json it automatically downloads the image file and names it as mysprites.json_image in the loaders resources. So you need to grab that, make a texture and upload it to the GPU. So here is the updated code:
let loader = new PIXI.loaders.Loader()
loader.add('http://mysite.fake/sprite1.json')
loader.add('http://mysite.fake/sprite2.json')
loader.add('http://mysite.fake/sprite3.json')
loader.once('complete', callback)
loader.load()
function uploadToGPU(resourceName){
resourceName = resourceName + '_image'
let texture = new PIXI.Texture.fromImage(resourceName)
this.renderer.bindTexture(texture)
}
loadSpriteSheet(function(resource){
uploadToGPU('http://mysite.fake/sprite1.json')
uploadToGPU('http://mysite.fake/sprite2.json')
uploadToGPU('http://mysite.fake/sprite3.json')
// helper function to get all the frames from multiple textures
let frameArray = getFrameFromResource(resource)
let animSprite = new PIXI.extras.AnimatedSprite(frameArray)
this.stage.addChild(animSprite)
animSprite.play()
})
Question 2
I never really discovered and answer but the solution to Question 1 has made my animations perfectly smooth so in my case, I see no performance issues.

html 5 canvas: using draw image in game makes loop very slow

i am making a game based on draw images and clear it every some part of second.
i started with:
var peng = new Image();
and then:
peng.onload = function() {
context.drawImage(peng, pengXPosition, pengYPosition, pengWidth, pengHight);
};
and in the loop:
var i=0;
function pengMoveRight(){ i++;if(i==1){peng.src = 'images/1.png';}else if(i==2)
{peng.src = 'images/2.png';} else if(i==3){peng.src = 'images/3.png';}else if(i==4){
peng.src = 'images/4.png';}else if(i==5){peng.src = 'images/5.png';}else if(i==6){
peng.src = 'images/6.png';i-=6;}}
when i run it it works well on IE but on chrome and mozilla it`s too slow and the character is about to disappear .. i used setinterval(); once and window.requestAnimationFrame(); once and both of them cause the same problem.
what should i do to make it smooth move?
here is the full script http://mark-tec.com/custom%20game/

Instead of changing the source, try to create several Image objects instead. That way, the drawImage call can always use a pre-loaded image.

You need to preload all the images or use the sprite method (all images packed into a single sprite) in order to avoid the initial delay caused by the image loading only when it's needed.
However, after that initial problem, your example should run fine once all the images are cached.

ThreeJS, Websockets, and NodeJS Client/Server Experiment

I was toying with socket.io, ThreeJS, Javascript, and NodeJS to create a simple client/server using ThreeJS's graphics. I wasn't sure if all of these frameworks would even work together, but I decided to give it a shot since I've seen similar examples online before even though I cannot find a simple one to dissect or experiment with. It's mainly to experiment with, but I also wanted to make a small little concept-game as proof of what I've learned so far.
I posted my code here: https://gist.github.com/netsider/63c414d83bd806b4e7eb
Sorry if it's a little untidy, but I did my best to make it as readable as possible.
Basically, right now the server-side NodeJS script seems to run fine (Run with "node server-alpha.js"), and the client script (client-alpha.html, which you can just open in a browser) connects to the server, and displays a list of users (who are also connected). However, my intention was for each user to be able to move his/her own cube around, and right now each cube only gets added to the screen (rather than being added, subtracted, and then added again - to give the illusion of movement). If you run both pieces of code and connected one or two users and move the arrow keys a few times for each, you'll see what I'm talking about.
Can anybody help me with this? I tried several different ways to remove the cube (and remembered to call render(), after each)... but everything I tried didn't seem to work. It always resulted in the cubes just being added to the screen, and never subtracted.
I added comments in the code to make things a little easier, as I know this is quite a bit of code to go through (if it's not your own, anyway).
Thanks, any help would be greatly appreciated... as I'm really stuck trying to make the cubes just move.
Also, I'm having trouble adding the Fly-Controls (FlyControls.js - it's commented out ATM), so if someone could tell me where I went wrong I'd appreciate that a lot also.

Ok so you don't want to keep remaking the cubes, all you need to do is change the position.
Also in game development, it is almost a requirement to use object oriented design, a good way to go about this would be to make a player object, so..
CPlayerList = new Array(); // an array of player objects
function ClientPlayer()
{
this.Cube;
this.Name = "unnamed";
this.Id = 0;
this.Create = function(name,pos,id)
{
this.Name = name;
this.Id = id;
var cubeGeometry = new THREE.BoxGeometry(10, 10, 10);
var cubeMaterial = new THREE.MeshLambertMaterial({color: 'red', transparent:false, opacity:1.0});
this.Cube = new THREE.Mesh(cubeGeometry, cubeMaterial);
this.Cube.position.x = pos.x;
this.Cube.position.y = pos.y;
this.Cube.position.z = 20; // don't know why this is 20, remember y axis is up & down in opengl/threejs
scene.add(this.Cube);
}
this.Move = function(vector)
{
this.Cube.position.set(this.Cube.position.x + vector.x, this.Cube.position.y + vector.y, 20);
}
}
So on the server you need a ServerPlayer object which holds similar data, and assign ids on the server before sending them to the clients. So when you send it to the client you want to make a new ClientPlayer, call player.Create() and then push it to the CPlayerList, like so:
function newCPlayer(data)
{
var newPly = new ClientPlayer();
newPly.Create(data.name,data.pos,data.id);
CPlayerList.push(newPly);
}
Then when you call your movePlayer() function, you can simply loop through your players array
function movePlayer(keyStroke, clientID)
{
if (keyStroke == 39)
{
CPlayerList.forEach(function(player,i,a)
{
if(player.Id === clientID)
{
player.Move(new THREE.Vector3(1,0,0));
}
}
}
}
This is just the client code, but this should help you get started, let me know if there's anything you're unclear on.
Also here's an example of a game using a similar design: http://82.199.155.77:3000/ (ctrl+shift+j in chrome to view client sources) and server code: http://pastebin.com/PRPaimG9

what is best to use canvas or img for frequent updates?

I have a javascript timer.
It refreshes the img src on a 200ms interval.
I have taken a look at the canvas object. I am unsure whether it is recommended to use the canvas instead of the img element?
I am running tests on both and cannot see any differences in performance.
This is my code for using the timer/img:
This is my code:
var timer4x4
var cache4x4 = new Image();
var alias = 'test';
var lastUpdate = 0;
function setImageSrc4x4(src) {
live4x4.src = src;
timer4x4 = window.setTimeout(swapImages4x4, 200);
}
function swapImages4x4() {
cache4x4.onload = function () {
setImageSrc4x4(cache4x4.src);
};
cache4x4.onerror = function () {
setImageSrc4x4("http://127.0.0.1/images/ERROR.jpg");
};
cache4x4.src = null;
cache4x4.src = 'http://127.0.0.1/Cloud/LiveXP.ashx?id=' + createGuid() + '&Alias=' + alias + '&ReSync=' + reSync;
reSync = 0;
}
*nb will add canvas code in a bit
I am streaming images from my client desktop PC to my web server. I am trying to display as many images (FPS) as possible. The image is a container for 4 smaller images. Stitched up on the client and sent to the server.
I have Googled and it says if doing pixel manipulation and aniumation use canvas.
But, I am just doing animation.
Thanks

The canvas element was designed to draw / edit / interact with images in it. If all you do is display the image, then you don't need that and a simple img is the semantically correct choice (with the added bonus of being compatible on more devices).
In both cases, the performance will be similar (if not the same) because the only thing to happen is that the image is downloaded.

While performance-wise you won't notice much of a difference, since you still cannot fully rely on HTML5 support yet, it is probably best to go with the img-solution for now.

KeyDown/KeyUp 70-120ms delay. How to reduce?

We're developing arcade (a lot of action and speed) browser 2d-game using canvas.
Sometimes our testing players report us that there is a delay: player still moving 5-10 pixels away after keyup.
I've digged this issue, you can see yourself delay http://jsfiddle.net/C4ev3/7/ (try keydown/up any key as fast as you can). My results is from 70 to 120ms. And i think that's a lot. (FYI, our network latency is 10-20ms).
Any ideas how to reduce this delay?
upd i've noticed that on good hardware this delay is under 30-40ms. But i'm testing on core2duo, winxp, chrome 19 - it's not a P4 with IE6 :)

Hi one thing you could do is instead of using an anonymous function try using defined functions,
http://jsfiddle.net/C4ev3/10/ - for me this reported at 50-100 MS
However i would not recommend jQuery for Canvas Applications it's very big for the very little you using, you should try using native Javascript
http://jsfiddle.net/C4ev3/11/ - for me this reported 30-70 MS
Javascript Threading
One thing i noticed in the comments Javascript is not Multi-Threaded Well Urm-Arr,
it sort of is setInterval is Async not Sync, however affecting the window is a single thread E.G if you have a Class that has some number is it using a setInteval will use another thread and not have a problem altering the math however in the Task then requires a Draw on the page it will enter the bottom of the JS handle Que,
Certain parts of Javascript are on a different thread how ever any thing changing the page has to run on the Main Thread same as any Windows application if your thread want to change the Form your have to invoke the main thread to do it for you
however it is not multi-threaded like any thing else you cant just handle or abort at a given Wim like windows,
Other ASync Tasks include AJAX has the option to be both Async and Sync
Updated to show my comment about FPS limiting:
Please bear with me. This is linking to a project that is allready built to show the example:
so my Game is Completely OOP
var elem = document.getElementById('myCanvas');
var context = elem.getContext("2d");
context.fillStyle = '#888';
context.lineWidth = 4;
// Draw some rectangles.
context.fillRect(0, 0, 800, 600);
context.fillStyle = '#f00';
var ball = new Ball();
var leftPadel = new Padel(10, 60, 40, 120);
var rightPadel = new Padel(750, 520, 40, 120);
pong = new Pong();
pong.draw();
setTimeout("ball.move()", pong.redrawTime());
Inside my pong class is where all the main workings of the game goes but here are the FPS bit you need to see
this.fps = 30;
this.maxFPS = 60;
this.redrawTime = function(){
return (1000 / this.fps)
}
this.lastDraw = (new Date)*1 - 1;
Then as you can see my Interval is on ball.move this calls the main pong class again on redraw at the End of the redraw i have the FPS checking and limiting code
this.fps = ((now=new Date) - this.lastDraw);
if(this.fps > this.maxFPS){
this.fps = this.maxFPS;
}
this.lastDraw = (new Date)*1 - 1;
if(this.reporting = true){
console.clear();
console.log("FPS: "+this.fps.toFixed(1))
}
setTimeout("ball.move()", pong.redrawTime());
This then forces you to get the Best Possible FPS without queuing the Main Thread

Try this:
e.stopPropagation()
Stops the bubbling of an event to parent elements, preventing any
parent handlers from being notified of the event.
e.preventDefault()
Prevents the browser from executing the default action. Use the method
isDefaultPrevented to know whether this method was ever called (on
that event object).
My min. results in Google chrome: 7ms