Category Archives: Flash

ActionScript performance tips

Here are a few simple tricks that may help the performance of your code/graphics intensive Flash movies. This is not an exhaustive list, by any means, rather some of the more effective performance tweaks to try out on your projects. There are the usual sensible coding tricks, like using local variables for oft-used references within functions, or planning your code loops carefully and breaking out of loops whenever feasible – but you should be doing these already. I’ll be adding to this post as and when I feel necessary, but will generally avoid the more granular tricks, such as bytecode optimisation. Some of those methods are too complex to explain in simple terms here and generally have a low effort-to-benefit ratio anyway:

Use scrollRect in conjunction with cacheAsBitmap. The cacheAsBitmap parameter of a movieclip can improve performance dramatically, but will cause problems if the render area of the movieclip gets too large (e.g. larger than 2880 in width or height), regardless of whether it is cropped by the viewable area of the Flash Player. The solution is to use scrollRect to constrain the rendering area to desired limits, in this example, the stage width/height:

Create bitmap snapshots of complex movieclips. Where you may have a movieclip full of layered graphical effects that isn’t animated, you can save a lot of rendering time by creating a snapshot of the movie. Similar to the cacheAsBitmap parameter, but will improve performance further if your movieclip comprises many lines or alphas. The following function shows a quick and dirty way of duplicating a movieclip as a snapshot of the original:


 

Use the opaque window mode trick – sparingly! Setting the wmode=opaque HTML parameter of your Flash object can improve rendering performance, but at a potential cost. Not only does it make the rendering order of movieclips and frames more ‘lazy’, but will effect keyboard interaction adversely in some browsers (especially FireFox). Use with caution.

I’ll be updating and tracking back to this post occasionally, so stay tuned…

InterServer Web Hosting and VPS
 

XML within a class

I was recently asked about the problem of loading XML from within a class to trigger an arbitrary method. The problem was: the onLoad event triggers on the XML instance, not the class creating it. This could probably be worked around with the Delegate class, but in the past I’ve simply extended the XML class itself, overriding the onLoad handler and adding a callback object that’s passed in (along with some error checking). It’s partnered with an XMLLoader class, the source and simple demo of which you can download here.

Wave your hands in the air

The London Flash Platform Users Group is running a meetup tonight about (among other things) connecting and controlling Flash with the Nintendo Wii controller – how cool is that? For those that can’t make it down to the Cosmo Bar in Barbican, they are apparently broadcasting the event here.

…see you there!

Vodafone ‘Mayfly’ website

How do you make the most of now?

I created this microsite for Dare Digital back in 2005, to promote a competition running alongside BBH‘s Vodafone ‘Mayfly’ TV campaign. Users can create a mayfly with a personal message attached, which lives for just 24 hours and wanders around the environment. The best life-affirming message won a drive around Monza with Michael Schumacher in his Ferrari!

Continue reading Vodafone ‘Mayfly’ website