Is there any significant performance/load time impact if single web page will load, say, 10 identical flash objects? 20? 30?.. any evidential data on sustainability of such kind of setup?
This would be the same flash app, each instance serving its own stream.
There's definitely going to be some overhead in size as there is a certain amount of code that is contained in every swf regardless of it's developer created content.
I'm almost certain there would be speed issues as well, which would see frame rates drop right down the more swfs you add to the page.
To be honest the concept smells a little fishy and i would think there must be a better solution to your problem.
EDIT
Also there is a restriction on having two steams coming over http per domain. Sure you could get around this but it will definitely be an issue.
I found this post which might help. The trick is to use SWFObject to embed your swf files.
I ran into a strange problem today. On the music charts page on Muziboo, I was displaying a list of songs and a playlist on the right. Each song has a small button player done in OpenLaszlo. In firefox everything was fine and in IE (not unusually), the page would freeze for sometime. This would happen once and repeat only if I delete cache and try again. I googled a bit and learnt that it's a good idea to embed give each swf a unique id otherwise the browser misbehaves. I then went ahead and used swfobject to embed the swf files and everything started working great!
Yes, it'll likely nuke the browser if you go too far down that road.
If you want to deal in multiple streams, perhaps combining all your would-be applets into one giant one might work better. It'll certainly offset the serious overhead you'd have with 10-40 of the little blighters.
If this is a music player, you want to have a serious look at doing some JavaScript remoting. It's fairly trivial to control a flash app via JS so you could have standard HTML/CSS controls without having to load up a billion flash instances.
Design-wise this just sounds like a bad idea. You'd be running multiple instances of the Flash player inside a browser, each of which has an individual cost, and the host (in this case the browser) will run all of them on the same thread (with the exception of certain elective asynchronous processes), so you're almost surely going to run into problems of various kinds -- jittery playback, UI blocking, processor burden, memory bloat, consequent instability of the host, etc.
Unless the SWFs are very tiny, and doing very little work, it seems like a design that's just asking for trouble. Indeed you could test such a thing fairly easily; have you run any tests yet? Just curious.
Also curious as to the requirements; we might be able to offer more constructive alternatives if we knew a little more about what you were aiming for. Have you considered simply loading all the SWFs into a single container SWF requiring only a single browser-hosted instance of the Flash player?
Related
For the past year I have been working on an isometric city builder. So far I have not used any framework apart from a loose PureMVC clone.
I have heard of Starling but only recently have I played with it.
From my research, the performance boost is fenomenal, but this forces me to manage my resource a lot tighter.
At the moment, I am exporting building animations one building at a time, in ~16 frames/pngs. These are cropped, resized and exported in Photoshop by a script and then imported in Flash, then exported as a swf, to be loaded / preloaded / postloaded on demand.
The frames are way too big to make a spritesheet with them, per building. I believe its called an atlas.
These pngs are then blited between lock() and unlock(). After the buildings + actors walking around are sorted, that is.
I am unsure if just using starling.Movieclip for the buildings, where instead of loading the pngs, I would build a MovieClip symbol with its frames. So bliting wouldn't even be necessary. Unless adding bliting on top of Starling would improve performance even more. That would allow fatter features such as particles effects, maybe some lighting.
Google isn't offering me a strait answer, thus I am asking here.
Google isn't offering a straight answer because there isn't such. It depends very very much on what you've done, how much knowledge you've got and what are your goals.
Using Starling gives benefits as well as drawbacks. Your idea of resources will change totally. If you really have enormous amount of assets, then putting them into GPU will be really slow process. You must start from there - learn what Starling does, how resources are managed with it and what you need to change in order to make the transition between the two.
If this is not that hard and time consuming task, you will have some performance optimization. BUT again it depends on your current code. Your current code is really important in this situation as if it's perfectly optimized your gain won't be that much (but commonly would still be).
If you need to switch between graphics regularly or you need to have dynamic assets (as images for example) you must keep in mind that uploading to GPU is the slowest part when talking about Starling and Stage3D.
So again, there is not a straight answer. You must think of GPU memory and limit, GPU upload time, as well as assets management. You also need to think of the way your code is built and if you are going to have any impact if you make the switch (if your code heavily depends on the MovieClip like structure, with all that frames and things) - it will be hard for you. One of the toughest things I fought with Stage3D was the UI implementation - there is almost only Feathers UI which will take you a few weeks to get along with.
On the other hand, Starling performs pretty well, especially on mobile devices. I was able to maintain a stable 45fps on a heavy UI app with a lot of dynamic loading content and multiple screens on an old iPhone 4S, which I find great. Latest mobile devices top at 60fps.
It's up to you to decide, but I'll advise you to have some experimental long-lasting project to test with, and then start applying this approach to your regular projects. I've done the dive to use it in a regular very tightened deadline project, and it was a nightmare. Everything worked out great, but I thought I would have a heart attack - the switch is not that easy :)
I would suggest using DMT for rasterizing your vector assets into Straling sprites at runtime, and it'll also keep your DisplayTree! meaning that you'll still have the parent/child relations that you had in your Flash Assets.
DMT will not duplicate assets, and will rasterize the vectors into texture atlases only one time (Cache is saved)
you can find it here: https://github.com/XTDStudios/DMT
I've found lots of information about measuring load time for pages and quite a bit about profiling FPS performance of interactive applications, but this is something slightly different than that.
Say I have a chart rendered in SVG and every click I make causes the chart to render slightly differently. I want to get a sense of the complete time elapsed between the click and the point in time that the pixels on the screen actually change. Is there a way to do this?
Measuring the Javascript time is straight forward but that doesn't take into consideration any of the time the browser spends doing any layout, flow, paint, etc.
I know that Chrome timeline view shows a ton of good information about this, which is great for digging into issues but not so great for taking measurements because the tool itself affects performance and, more importantly, it's Chrome only. I was hoping there was a browser independent technique that might work. Something akin to how the Navigation Performance API works for page load times.
you may consider using capturing hdmi capturing hardware (just google for it) or a high speed camera to create a video, which could be analyzed offline.
http://www.webpagetest.org/ supports capturing using software only, but I guess it would be too slow for what you want to measure.
I'm dealing with an audio anomalie. I have audio that is mastered quite loud, yet on some systems, it is too quiet. Boosting the audio file anymore causes clipping.
It would be fine, except for the fact that, in my project, a lot of other sounds are in use as well. Lowering the volume of everything to match this would make some stuff impossible to hear. And again, this doesn't happen on all computers, only some.
To compensate, can I boost audio in code? The SoundChannel I'm using is already at 1.0 volume (full), and I know I can't use that property to boost it further. Is there any way to raise the audio further in code?
(I'm using Flash Professional CS5.5, Adobe AIR 3, and ActionScript 3)
After some time, I've concluded that it is apparently not possible to boost sound volume above 1 (that is, to amplify) using Flash's API. While you can set SoundTransform to a number greater than 1, it will coerce to 1 nevertheless.
If anyone has information to the contrary, you are welcome to post the answer and I'll change which answer I've accepted if you solve the problem.
You are correct. Sounds cannot be played at a volume above 1 (100%). However -- You can play two identical sounds simultaneously on different channels. This would effectively give you an audio boost above 1. But depending on the nature of the sound you may get some distortions from synchronization. If you're talking about a sound-effect without a lot of discernable Attack, you may get away with it. If you're talking about speech or percussive sound, your mileage may vary.
I'm working with a project where we are running a projector from/on a CD, and this can't be changed, to run an e-learning program of sorts. Everything is included on the CD and it doesn't need anything else to run, ie all imgs and xml and whatnot is on the CD.
The problem is that on some computers, assumedly less powerful ones, the entire process clogs up and instead of showing the images just white blank areas appear. The imgs used have been downgraded to a lower resolution, from 1333x1000 to 800x600, and this has solved the problem from what we've found so far.
My question is, does anyone know of any other way to solve this without cutting down the img quality?
As it is right now all the pics (about 180 i think) are being loaded right when the process starts and one idea i have is that you load the pics gradually as needed, 2-3 in advance back and forward or maybe an entire chapter even (7 chapters with imgs are used), to always ensure smooth tweens without having to wait for loading.
But as I've read that there seems to be some memory issue when using a flash projector on a CD/DVD, I'd also like to get more details on what the actual problem is and if possible to find more solutions to it.
I found some links that were supposed to target Adobes own views on the problem, but these links were obsolete. (links found here http://www.flashjester.com/?section=faq&cPath=14_23#394).
Any ideas, help, links, tutorials and what not are welcome.
Yeah, you need to load your assets on-demand and be careful about references so unused things are really garbage collected when they aren't needed anymore.
If you are really running from a projector, then load times aren't totally a concern. Assets form the local filesystem are always available the next frame; they aren't streamed from the disk like from the network. However, bigs file or ones with lots of exports may end up with a longer frame time, or a noticeable delay.
You also need profile things to see if your changes are actually doing anything. Poke through the flash.system.System class to see how you can get info, or take a look at SWFProfiler.
I am developing a jQtouch app and each request done via ajax creates a new div in the document for the loaded content. Only a single div is shown at any one time.
How many div's can I have before the app starts getting unresponsive and slow?
Anyone have any ideas on this?
EDIT: Its an iPad app running on Safari, and it would be less than 1000 div's with very basic content
I've had tens of thousands, maybe even a hundred thousand divs, on screen at once.
Performance is either fine, or bad, depending on:
Parsed from HTML or generated Dynamically in JavaScript?
Parsed from HTML means you have a LARGE html source, and this can make browsers hang. Generated in JS is surprisingly fast, even on Internet Explorer, which is the slowest of all browsers for JS.
To be honest, if you really need an absolute answer to this question, then you might want to reconsider your design.
No answer given here will be right, as it depends upon many factors that are specific to your application. E.g. heavy vs. little CSS use, size of the divs, amount of actual graphics rendering required per div, target browser/platform, number of DOM event listeners etc..
Just because you can doesn't mean that you should! :-)
As others have said, there's really no answer.
However, in this talk about the Google Maps API version 3, the speaker brings up the number ten thousand several times, as a basic threshold for browser unhappiness.
http://code.google.com/apis/maps/documentation/javascript/
Without defining a particular environment, it's not possible to answer your question.
And even then, anything anyone tells you is just a guess. You need to do your own testing on real-world configurations with different browsers and hardware. You'll also need to establish some performance benchmarks to decide what "too slow" even means.
I've been able to add several thousand divs without a problem. Depends on what you'll be doing afterwards, of course, and the memory on the client machine. Everyone else is right about that.
As Harpo said, 10K is probably a good ceiling. At one time, I noticed speed problems starting at about 4K divs, but hardware has improved since then.
And, as Neil N said, adding the divs via scripting is better than having a huge HTML source.
And, to answer Harpo's comment, one way to "break it up" so that JS doesn't lock the page and produce a "page is running slowly" error is to call a timer at the end of each "add a div" routine, and the timer in turn calls your "add a div" function again.
Now, MY question is: is it possible to "paint" so that you don't need to add thousands of divs? This can be done with the canvas tag with some browsers, but I don't think it's possible with VML (the excanvas project) on IE. Or is it? I think VML "paints" by adding new elements to the DOM, at which point you may as well use DIVs, unless it's a simple shape.
Is it possible to alter the source of an image via scripting? (the image in the DOM, of course -- not the original image on the server.)