Here’s the link to Adobe’s AIR overlay instructions: LINK

Here’s a quick reference to the Mac Terminal command that uncompresses the SDK package and overwrites all files: sudo tar jxvf AIR15_mac_sdk_XXXXXX.tbz2

Tools

• Pix LINK (Windows)
• gDEBugger LINK, Win, Linux, Mac OS 10.6 only)
• Adreno Profiler LINK, Android with Qualcomm GPUs)

The framework is clever and is a great starting point for understanding Stage3D optimization. I was surprised to see that a framerate measurement layer was placed over the top of the Stage3D content in a traditional Display List layer. It was my understanding that any Display List content over Stage3D would have a significant performance impact. To test this, I modified the sample to display the framerate in a new Stage3D layer and ditched the Display List (actually, you can toggle between the 2 views).

Grab a copy of my modified project here:
BunnyMark Stage3D Update

Results
Surprisingly, performance was not impacted on the desktop and on an iPad1 it was only minimally impacted (perhaps a 1-2 fps savings, but erratic). I am surprised that the mix of Display List and Stage3D content does not cause more diminished performance.

A few notes on my approach to the modification
The Adobe GPUSprite framework was designed to specify UV values for a Sprite just once and never change the UV values for that Sprite. For the display of numerals in this app, I wanted to try shifting the UV values associated with each Sprite numeral rather than removing each of the numeral Sprites and adding a new replacement Sprite for each numeral. I extended a couple of the GPUSprite classes to enable UV shifting.

Some changes and features of the modified app

• Click in the top-left corner to toggle between Display List and Stage3D view.
• I use a single shared framerate counter to provide content for both the Stage3D FPS display and the DisplayList FPS display.
• I scale-up the small Stage3D text without smoothing (that’s why it looks chunky). I could have just used a larger source bitmap for the numerals, but I wanted to give this a try (enlarging a Sprite without smoothing for an exaggerated pixellated look).
• I didn’t modify the Adobe framework classes. I had to extend a couple of them to make the UV updating work.

Here’s a way: Instead of using the *new* operator to create the Vector use global conversion to convert an Array into a Vector (note that the *new* operator is not used in the sample):

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var samples : Vector.<Number> = Vector.<Number>( [ 1.0, 2.0, 3.0 ] );

Another pretty straightforward technique is to instantiate an empty Vector then push all the values with a single push method call:

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var samples2 : Vector.<Number> = new Vector.<Number>();
samples2.push( 4.0, 5.0, 6.0 );

You may wonder if you can pass an Array to a Vector constructor — nope, the Vector signature specifies 2 parameters: length of the Vector and a Boolean that can be used for locking the length of the Vector. Passing an Array to a Vector constructor yields an empty Vector.

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// Sample that fails to create a pre-populated Vector, 
// but it does create an empty Vector.
var samples3 : Vector.<Number> = new Vector.<Number>( [ 7.0, 8.0, 9.0 ] );

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// Output from prior 3 samples
trace( "samples: " + samples ); // output: samples: 1,2,3
trace( "samples2: " + samples2 ); // output: samples2: 4,5,6
trace( "samples3: " + samples3 ); // output: smaples3 (an empty Vector was created)

Thibault Imbert from Adobe posted the com.adobe.utils package in this blog post: http://www.bytearray.org/?p=2555

It contains these 3 classes:

• PerspectiveMatrix3D.as
• FractalGeometryGenerator.as
• AGALMiniAssembler.as

Here’s the direct link:
http://www.bytearray.org/wp-content/projects/agalassembler/com.zip

Here’s how to capture a screenshot of various mobile devices while they are running:

iOS:
Press-and-hold the home button then while still holding the home button down press-and-release the sleep button. The screen will flash white and you’ll hear a snapshot sound. Tested on iPhone 3GS and iPad v1.

Android:
Only solution is with a connected computer. Use the Android SDK softwware while the device is attached to your computer. http://www.addictivetips.com/mobile/how-to-take-screenshots-of-android-device. Tested on Google Nexus One.

BlackBerry PlayBook:
Press the Volume Up and Volume Down buttons at the same time.

Q: If you have a fullscreen SWF how do you prevent the display from returning to normal size display when the user presses the ESC key? An example case where this would be useful is pausing a fullscreen game and displaying an in-game menu.

A: I thought overriding the default behavior might pose a security risk, however it is not restricted. Listen for the associated keydown event for ESC and call preventDefault() on it.

You can prevent the default behavior for some other events as well. You can prevent input text from appearing as the user types, prevent double-click text highlighting, and more. To determine if an event has a default behavior that can be prevented check if the Event.cancelable property is true.

Adobe Help Reference Doc for the preventDefault() method: LINK

I was unable to make the stats module show up. I confirmed that it existed on the display list by tracing from its update method, but it wasn’t being shown on the screen. After poking at it for a while I discovered that by drawing additional content into the graphics layer of the Stats object after it is initialized I was able to force it to be shown. There may be other solutions and this may be limited to my particular configuration, but if anyone encounters this, here’s a hack that works. Below are the 3 lines that I added after initializing the Stats object. Commenting-out the 3 lines and changing nothing else will cause the Stats object to disappear. I can’t explain why — the source code looks fine.

_stats = new Stats();
_stats.graphics.beginFill(0xFFFF00);
_stats.graphics.drawRect( 0, 0, 2, 2 );
_stats.graphics.endFill();

Project build on Windows 7 (64bit), FDT 4.5.2.1328, Flex 4.5 SDK, AIR version 2.6, Standalone Flash Player 10.3.181.26

* please note the revised syntax and description from Holly Schinksy:
<key>UIApplicationExitsOnSuspend</key>
<true/>
http://devgirl.org/2011/06/24/exit-vs-suspend-your-ios-application/

Here’s a couple of discussions on the Adobe forum: http://forums.adobe.com/message/3771534
http://forums.adobe.com/thread/870733

On Android, you can respond to the Deactivation event from the system and call NativeApplication.nativeApplication.exit() before your application is deactivated. Apple apps don’t seem to respond to the nativeApplication.exit() method.

import flash.desktop.NativeApplication;
// ...
NativeApplication.nativeApplication.addEventListener(Event.DEACTIVATE, handleDeactivate, false, 0, true);
// ...
private function handleDeactivate( event:Event ) : void 
{
	NativeApplication.nativeApplication.exit();
}

Be careful if you try this on BlackBerry’s PlayBook. I submitted an app that did this and it was rejected for it. You may have success submitting an app with auto-close if you explain that it is the intended behavior.

Note that there is some debate about the preferred action when an app is Deactivated. Some prefer to allow it to go into an idle mode that uses little system resources (called Tombstoning), while others prefer to kill the app outright. Here’s a blog post from “fjenning” at Adobe on Tombstoning:

http://blogs.adobe.com/ria/2011/04/20/tombstoning-in-air-mobile-applications/

EDIT: 3/24/2012
I recently found that when using the NativeApplication.nativeApplication.exit(); method and testing the SWF in the Flash Player Debugger, an error was thrown because the SWF was running outside an AIR environment. The same SWF showed no errors when running inside an AIR environment. I wrapped the line in a try/catch statement to solve the problem.