ActionScript 3.0
A couple of years ago, I created an object pooling utility for a games project I was building in AS3. Since then, I’ve used it quite a few times, in order to speed up apps and improve resource management, easing the load on the garbage collector by reusing objects instead of recreating them. Continue reading Loan Shark – fast object pooling utility
In a simple situation, where you wish to add many elements to an Array or Vector, you might just do:
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var input:Array; var output:Array; while (input.length) output.push(input.shift()); |
However, the sizes of both Arrays are manipulated for each loop, which will have an adverse impact on speed and memory usage. So, we could cache the length of the input Array and not manipulate it:
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var input:Array; var output:Array; var inputLength:uint = input.length; for (var i:int = 0; i < inputLength; i++) output.push(input[i]); |
But we’re still growing the size of the output Array incrementally, which is very bad. Since we know input.length in advance, we could grow the output Array to its new size just once, before the loop:
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var input:Array; var inputLength:uint = input.length; var output:Array; var outputLength:uint = output.length; var newOutputLength:uint = outputLength + inputLength; output.length = newOutputLength; for (var i:int = 0; i < inputLength; i++) output[i + outputLength] = input[i]); |
This is OK, but still involves a loop. If only we could push multiple elements into the push method in one go. Well, we can – enter the apply method. Since Array.push accepts multiple arguments (something rarely used) and apply allows us to pass an Array of arguments to any Function, one line and we’re done:
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var input:Array; var output:Array; output.push.apply(null, input); |
This works out faster and more memory efficient than the other methods. It works nicely for Vectors, too. If anyone has a faster method of doing this, do let me know.
If you’re still churning out Flash banners, please use this!
I created this simple utility, called SWFIdle, to enable the Flash Player to lower its CPU usage while the user is not interacting with it. Since it’s possible to have multiple Flash instances embedded in one page (for example, a game and a couple of banners), I recommend using this in your projects, so that Flash instances needn’t fight for CPU and give Flash a worse name than it has already 😉
I know there’s the hasPriority embed attribute now. But:
You need to use some kind of Dependency Injection (DI for short) to provision some System Under Test (SUT for short) in tests you’re writing, but can’t or don’t want to use a DI framework to do so.
Alternative titles for this post include:
My ScratchPad app for Blackberry Playbook is now live. It’s a simple drawing app where you can export your creations to the image gallery. When the BlackBerry Playbook launched, there was nothing like this available, so I created it 🙂 If the Playbook does well, I’ll be creating more apps for the platform – it’s certainly a nice piece of hardware and BlackBerry OS is easy enough to work with.
