http://www.adobe.com/devnet/flex/videotraining.html

optimising art on flex mobile


http://tv.adobe.com/watch/max-2010-develop/optimizing-flash-player-compatible-content-for-mobile-devices/

MMugDUblin Preso: http://adobechats.adobe.acrobat.com/p4x9a579we9/


Tips:

go for vector graphis only if you need to scale the graphic otherwise go for bitmap graphics


convert fxg to optimise it for bitmap


video target h.264 optimized by hardware

Audi target AAC, dont embed media or fonts


Flash Rendering optimisations



Rendering Tips


Reduce frameRate can make smoother playback default frame rate in flash builder

set stage quality low medium high best

use appropriate DisplayObject (Shape, Sprite, MovieClip)

nb use shape rather than sprite if possible, no children

Flatten the DisplayList Tree, when you add or remove children, the more nested the greater the problem

Avoid alpha property

Avoid unnecessary masking

stop running MovieClips

Avoid off-stage objects

"visibility=false" vs. "removeChild()"

Understanding cacheAsBitmap

Creates a snapshot of a DisplayObject and uses it when rendering useful if you have a complex background


uses GPU if available on mobile devices, sometimes can be a disadvantage especially if cached bitmaps are changing a lot

use Show Redraw Regions to see when areas are being withdrawn, right click and select in flash

CacheAsBitmapMatrix allows you to perform rotations using the cached Bitmap...requires two bitmaps in memory


tool for keeping tabs on performance on mobile devices

sprite.cacheAsBitmap

flash.profiler.showRedrawRegions  you need debug player

unknowns? 
                     BLITTING

Avoid Blending and Filtering very cpu intensive get updated every frame

consider prerendering the filter Use pre=rendered/pre-filtered graphics


Blend modes awesome but cpu intensive

BitmapData manipulation & Blitting several bitmaps are composited onto one bitmap, copy pixels most used using the class for this

canvas.copyPixels(spritesheet, rect, new Points etc




Stop running MovieClips


MipMapping

caches downsized images for faster rendering

improves performance when reszing and antialiasing bitmaps

Quick tips

Focus on perceived performance


use cacheing pooling and free memory, set variables to null when requires

mr doob's stats class to keep an eye on memory plus profiler

grant's performance test class

Embrace Constraints


http://tv.adobe.com/watch/adc-presents/migrating-to-flex-4-using-skins/


Mr Doob:

http://code.google.com/p/mrdoob/source/browse/trunk/libs/net/hires/debug/Stats.as


Renaun Erickson
http://www.adobe.com/devnet/flex/articles/flex4_skinning.html

using skinClass define a new class based on the button class and make all the changes you want