I have 25 kind of heavy movieclips on the screen. They show many bitmaps, each one of in one of their frames. The problem is that the application gets unusable when they are on screen. And even after removing them the app keeps slow.
Using Adobe Air 2.0, compiled by Flash CS5.
There literally thousands of optimization tricks for Flash, but one that usually helps when dealing with large (or complex) Sprites or MovieClips is the cacheAsBitmap property:
my_mc.cacheAsBitmap = true;
And since you are using Adobe Air, you can also have access to the cacheAsBitmapMatrix property, for further optimization (badly needed on mobile devices!):
my_mc.cacheAsBitmapMatrix= my_mc.transform.concatenatedMatrix;
my_mc.cacheAsBitmap = true; //also this!
Check out this Republic of Code tutorial about when/why better use them.
Hope this helps!
Related
I'm trying to do some animations using Java3D on a Mac.
If I use universe = new SimpleUniverse(); to create a universe, everything is fast. The problem is that there's a bit of tearing sometimes because I'm altering object properties while in the middle of rendering. What I would like to do is stop the rendering while I'm updating properties.
My first step was to try creating my own Canvas3D, and that's where things went wrong. Rather than just creating a SimpleUniverse, I do this sort of thing:
GraphicsConfiguration config = SimpleUniverse.getPreferredConfiguration();
canvas = new Canvas3D(config);
universe = SimpleUniverse(canvas);
When I do this, the first problem is that the window doesn't automatically appear. So based on the example at java2s, I embedded the Canvas3D in an applet. Then I get a window, but performance is TERRIBLE. The rendering is MUCH slower.
It's almost as though the rendering is no longer being done by the graphics engine but instead in software.
Can anyone give me some tips as to what I'm doing wrong here?
Thanks!
You should try compiling your BranchGroups before they become live. This helps preprocess the objects before they get displayed in the universe. It might also be something else that java is getting hung up on, if you put the whole source in the question, then i could tell you more. It might also just be your computer, Java3D takes a big hunk of Memory and is pretty CPU intensive, your computer specs would also be relevant in answering this question
Hope that helped you out a little bit, if you add more to your question i would be happy to help you more
I’m building a mobile web application, and even though I’m still in a prototyping kind of the process, I’m having a hard time fixing certain performance problems.
The application itself (works all smooth in desktop browsers, but significantly sluggish in Mobile Safari): Hancards webapp prototype. You may login as mifeng:wangwang or create a new user.
The overall clumsy performance could be tolerable though, except for one thing: the browser simply crashes (!) when you open a set page, tap ‘view’ (enlarge all cards) and then try to go back to the previous page.
The code that gets executed when ‘view’ is tapped is this (very sluggish by itself as well; any way to improve it?):
if ($(this).hasClass('big')) {
$('.card').unwrap().removeClass('big flippable').addClass('small');
$(this).removeClass('big');
}
else {
$('.card').wrap('<div class="bigCardWrap" />').removeClass('small').addClass('big flippable');
$(this).addClass('big');
}
And another thing, a pretty weird bug. Very often the ‘word of the day‘ block won’t display the text node for the last element (<div class="meaning">), even though it’s in the code. The text will not show unless you ‘shake’ the DOM anyhow (unticking and ticking back one of the associated CSS properties can also achieve that). This happens in both desktop and mobile Safari browsers.
The code that writes it in there is this:
// While we are here, also display the Word of the day
$.post('ajax.php', {action: 'stuff:showWotd'}, function(data) {
// Decode the received data
var msg = decodeResponse(data);
// Insert the values
$('.wotd .hanzi').text(msg.content[0]['hanzi']);
$('.wotd .pinyin').text(msg.content[0]['pinyin']);
$('.wotd .meaning').text(msg.content[0]['meaning']);
});
I don’t expect you to advice me on how to fix the performance of the whole application (I will probably have to revise the overall scope of the project instead of trying to find workarounds), but I at least would like to see how to solve these two problems. Thank you!
The only performance issue I see in the script is the wrap/unwrap calls - adding and removing elements from the DOM tends to be fairly slow, and you can probably get the same effect by always having a wrapper element and changing its class rather than adding or removing it.
However, the performance issues you are seeing are most likely in your css:
3D transforms can be much faster than 2D due to hardware acceleration. It looks like you already have this, though you do need to be careful about which elements it is applied to
Shadows have real performance issues, especially when animated. Removing them will probably fix most of the slowness.
Rearranging background images can help - A single background image under transparent pages is faster than having a background image for each page.
I have a scenario that I need some good solid advice on. The question is really about speed of WriteableBitmap vs. images in IsolatedStorage on the Windows Phone.
I have an app that displays a UserControl (#1) which is a little graphically heavy. When the user swipes it, it transitions in a push-left type of transition to bring in a new UserControl (#2) which is also a little graphically heavy. If the user swipes the other way, control #1 is brought in in the same type of push-transition, this time from the right.
What I do today is take a snapshot of #1, load #2 off screen and take a snapshot of it, put both side-by-side in a Canvas control and animate that control either left or right. One of the reasons I don't just use the controls and animate them is they may have animation that starts when they are loaded - my current technique allows me to capture a screen shot of pre-animation and post-animation, depending on which direction they go in.
What I'm wondering, however, if it would be better/faster to just do the above the first time and send the writeablebitmap to IsolatedStorage with Extenstions.SaveJPEG and just use that instead in subsequent tranistion animations.
Would load/render/WriteableBitmap each time generally be faster or load jpeg from IsolatedStorage be faster each time? I see that the Transitions control in the SDK doesn't really do either of these, so I'm open to suggestions that are different that also might improve performance.
I expect this to be very depended on the hardware and application. So it is pretty hard to give an answer based on this input. It doesn't look to hard to test (on actual hardware and with the actual application) so my advice is to build both and test.
The applications I have been working with use both approaches and to be honest I haven't noticed much difference.
Also you might try and enable bitmap caching on the controls. This will give you a writeable bitmap implementation that is very fast.
I am making digital instruments for a car. These instruments will be constantly updated by information through ajax. These instruments will be served from a server onboard the vehicle through WLAN (fast) to my iPhone 3G. Is imperative to the success of the project that the updating of the tachometer is smooth and very responsive. Otherwise, it will look retarded.
The first problem I encountered was when I made this demo where tachometer moves quickly back and forth between zero and a thousand RPM: http://www.kingoslo.com/instruments/ When viewed on my iPhone 3G, the arrow simply doesn't move back and forth smoothly enough.
This javascript works by changing the source of the arrow img-element (which is semi transparant {4 color png} floating on top the static picture of the scale {16 color png}, by the way).
I've been made aware of new image editing features in HTML5, and wondered if any of those, or any other methods will be more responsive. Also, I am getting an iPhone 4 for xmas, so that may be a bit faster, but I've got the feeling that it still will fall short for the current build, especially when I add the constant ajax updating that is required to keep the instruments change values as the driver drives along.
Thank you for your time. Any help is greatly appreciated.
Kind regards,
Marius
I think using canvas will result in much faster animation - it was created to handle drawing, whilst manipulating DOM elements is comparably expensive.
Mobile Safari is compatible with canvas.
Alternatively, you could try incorporating all the angles as one large CSS sprite, and then just manipulating its background-position CSS property (element.style.backgroundPosition in the JavaScript DOM API).
See here: http://code.google.com/p/ie7-js/
Does anyone have any experience or remarks about this javascript? Is it worth including? Do you recommend it?
I know many people, myself included that are using various IE hacks to get transparent PNG support. THis looks like a little bit more help, and as long as it works, and the size is fairly small, I wouldn't see much against using it.
I've used it before, and my results are mixed. Those scripts cause IE to churn for a bit on page load. Basically, you have to think of it as iterating through Elements and stylesheet rules to apply "fixes" for areas that are deficient in that particular rendering engine. In some cases, depending on how complicated your markup or stylesheets are, that can take a bit of time and you will see the browser hang.
That said, if you can trade off that performance cost, you will save development time as you'll spend less time hacking around IE6 quirks; IE7/IE8 will provide enough missing functionality that you can avoid certain edge cases, can develop using standards better (min-width/min-height, multiple className selectors, etc.), and certain rendering issues will disappear.
However, if you just need 24-bit transparent PNG support, use a tool built for that. Including IE7/IE8.js for PNG support alone is like pounding in a nail with a tank. Use DD_belatedPNG for that.
It works, but its worth keeping in mind that ie7.js and ie8.js do much more than provide transparent PNG support. Even with the transparent PNG support, its worth keeping in mind that transparent background images cannot be tiled (repeated) using background-repeat or positioned using background-position. This hinders any ability to use CSS rollovers using background-position. I've only used it on one site I've done, and now that I'm updating the site I can't remove the ie8.js because if I do the entire website breaks layout in IE. I don't believe I'll be using it in the future, and instead rely on simple CSS hacks or simply allow my sites to "degrade gracefully" in IE6.
I know that there are some tools for fixing the transparent PNG problem which are more flexible than this. For instance, the jQuery plugin ifixpng2 will support background position, which ie7-js doesn't do.
As long as you are aware of exactly what it fixes, I would say go for it. I'm not sure about this lib exactly, but some libs get very expensive if you have a large DOM, as they tend to hook in HTC file base behaviors on EVERY DOM Element. This causes the dreaded "Loading x of y" status bar message to flash constantly on the initial load, and any newly generated DOM content.
well its beautiful and works grate way u can use cs3 features like li:hover. we did lost of project last time using ie8.js and it works great way.