This post is to summarize my session at the FlashCamp.

Here’s the preso: (italian only)

and here are the examples shown during the session:

Garbage collector in action:
this example shows the memory allocation behavior. Take a look to the saw tooth yellow line in the graph.

Weak vs Strong references:
two examples to show the difference between weak and strong references: basically weak do not increment reference count, strong do that.
If you store keys in a dictionary using weak references your keys are getting cleaned by the garbage collector ( example )
otherwise the GC doesn’t clean your keys ( example ).

Blitting in order to ease the GC:
The GC iterates through each reachable node starting from the roots, one of these roots is the displaylist. So in order to ease the GC work we could flatten the whole displaylist to one bitmap by leveraging the usage of the blitting technique.
These examples display about 1000 new objects drawn each frame by using the display list ( example ) or the blitting technique ( example ). The difference in performances are not only due to the different compositing techniques (built in compositing when using the displaylist VS manual compositing when using the blitting technique ) but also to the lower number of instances to be collected by the GC.

NOTE: both examples are very cpu intensive

Don’t let the GC start by using the memory pool technique:
The GC freezes the program when freeing the memory. The memory pool technique consists in reusing the instances of your objects preventing the GC to identify those objects as garbage.
This makes your app memory utilization stable (a straight yellow line ) and removes every glitch due to the garbage collection.
These examples show a simple particle fountain implemented by leveraging the memory pool technique ( example ) or not ( example ).

Finally:
here’s the source, it’s not the best commented nor the best implemented files out there, but just take a look at them to have a full comprehension of what’s going on

If you need further help, please comment this post and let me know.
ciao

PS: obviously mario copyright is property of nintendo

Yesterday it has been a great day!
Yesterday we had the FlashCamp here in Milan, hosted by WhyMCA mobile conference (thanks guys).

Lots of fun, lots of people (450 nerds) from the most different beliefs (html5ers, javascripters, objective-Cers, androiders, whateverers ), a great happening to spread the word about what you can do with the flash platform and how it can ease your work when deploying on mobile devices.
Thanks to Adobe we even had a welcome guest: Mihai Corlan, who presented very cool new stuff putting his hands on Flex Builder 4.5 and the Flex Hero SDK.
Moreover it has been totally the best possible way to meet other people from the community of Milan, TheFlashMind, and to spread the word about our cool AUG

I really enjoyed the FlashCamp, it has been a pretty unique conference in Italy and it has been even more successful than we expected.
As the camp was in “Eataly” we had an Eatalian FlashCamp party at the end, a cool way to make developers meet each other and to make them drunk
Someone even twitted that it was the best part of the FlashCamp in Milan

Last but not least: my friend Luca already uploaded some pics to his flickr account.

See you at the next camp

Just bought my ticket for Flash on the Beach 09! w00t!
I really can’t wait to reach Brighton and attending such a great conference.
See you there guys