As the Vector and Vector3D classes are well optimized, I wanted to optimized my own loops.

So came again the question : "What is the most optimized loop system for these classes ?"

So i wrote a quick "while loops" performance test where i use a huge Vector array of Vector3D instances where i tried several systems.

I firstly thought that there was no way using the "for loops", but i read this quite interesting article :

http://www.experts-exchange.com/articles/Software/Photos_Graphics/Web_Graphics/Macromedia_Flash/ActionScript/20-Tips-to-Optimize-your-ActionScript.html

and i finally put the for loop test as the last test.

Each test performs a vector crossproduct on each Vector3D, and this for 2 millions vectors !!!

clear here to start the while-loop test

I was used to coding my loops with the first loop test :

i = vect.length;
while(i--){}

but apparently the most optimized loop on my mac (imac 27") should be the 3rd test :

i=vect.length;
while (--i>=0) {}

For my computer (Mac/Firefox) each test of the benchmark is almost the same, even the "for loop" which is quite efficient.

But I look closely, the fact is was using the less optimized while loop (according to this test)...

It's up to you to test your own computer and may choose one of these loop.

Looking on the web, the ".profile" file has to be changed, but i couldn't find it... the reason : I had no ".profile" file on my system....

So if you don't have any ".profile" file in your home directory (your nickname directory), here are the steps to follow :

1) First of all, you may want to show hidden files on your mac to see exactly what you do,  to do so type the following lines in your terminal:

defaults write com.apple.finder AppleShowAllFiles TRUE
killall Finder

• change TRUE/FALSE to activate/deactivate the option
• killall Finder will close all finders as it has to be restarted

2) Then create a new file in TextEdit for example and add this :

export PATH=$PATH:/usr/local/bin:/Applications/flex_sdk_3.5/bin

(in my example I unzipped the flex sdk in my Applications generic folder)

This will add the flex bin folder path in your system path.

3) Now save the file as ".profile" in your your home directory

4) Now you have to load/reload your ".profile" to make it active, type this in the terminal :

open a new Terminal so that it opens in your home directory and type:

. ./.profile

this will reload the file

5) test if your path has been integrated in the $Path variable, type

echo $PATH

6) Final step, check if Flex SDK is now available :

just type "adt" in your terminal and you should not have any error

That's it, if you want to check if your path

As you may know, some tools like firebug helps you tracing incoming and outcoming data between flash and scripts, even if you use POST data.

See below how firebug can trace all variables sent through the POST data :

firebug tracing

So i tried to figure out how to implement a crypted system to secure (a little bit more) these data, with an encryption key if possible.

I found the useful project on the web : as3crypto project

Thanks to this class, you can crypt/decrypt in flash but as far as i looked the sources, there was no information about crypt/decrypt on php side.

But i found another message in a forum where a php code was given, so i mixed both to provide you a simple way to set both sides.

In my example, flash send some data to php using crypted message and PHP answer another crypted message (+ the original decrypted flash message for verification):

• Using the php class : cryptlib.php

1. create an instance of the class, and call the init with the crypted key as parameter
2. decrypt the sent message (using POST object)

include_once "lib/cryptlib.php";

// init a new instance of Crypto Class
$crypto = new Crypt;

// init with the encryption key
$result = $crypto->init("PASSWORD");

// get the POST data
$messagefromflash = $_POST ["message"];

// decrypt data
$decrypted_messagefromflash = $crypto->decrypt(utf8_decode($messagefromflash));

but you can also send back crypted data to flash using the "encrypt" method

// return a crypted result to flash
$resultmsg = "Ok, i received your data, everything is fine !";
echo "result=".$crypto->encrypt(utf8_encode($resultmsg));

• Using the as3 class : CryptoCode.as

1. in your main class, create an instance of the CryptoCode class that will crypt/decrypt your data.
2. call the init method with the same key as PHP (just like PHP code)
3. then call "encrypt(s:String)" or ""decrypt(s:String)" methods through your crypto instance

// instance of crypto class
 private var _crypto : CryptoCode;
 public var myLoader : URLLoader;

// create instance with encryption key
 _crypto = new CryptoCode("PASSWORD");

// send crypted string to php script
 var variables : URLVariables = new URLVariables();
 variables.message = _crypto.encrypt(tosend_in.text);

// create request with POST method
 var request : URLRequest = new URLRequest("http://www.lecrabe.net/wordpress/demo/crypt/scripts/testcrypto.php");
 request.method = URLRequestMethod.POST;
 request.data = variables;

 // send request
 myLoader.load(request);

If you want to get the whole example, please download the sources.

Enjoy.

The blog turned into wordpress blog, and here is a handy tool I wrote for my personal use in the first place :

Mac File Cleaner is a tool for people who work on both Mac and Windows platforms.

Every time a mac user send files to a windows user, many hidden files appears in the windows system : "._*" files and ".DS_Store" files.

These annoying files may be a problem as in my personal project, so MFC will solve this problem in 2 steps :

1) place the MFC executable file in the root folder where you want to remove those mac files

2) run MFC, and it will recursively remove every mac files

STEP 1 :

The mac files cleaner is placed at the root of the project.

STEP 2:

MFC indicates where the recursive operation will start from, then click CLEAN button

STEP3 :

MFC deletes all mac files recursively and shows you the scanned folders and deleted files.

If wrong files are deleted, they may be found in the system trashcan.

Download Mac Files Cleaner

Enjoy.

I had a strange bug in eclipse : when creating sources folder or a new class while another folder is selected, the new folder is created on root of classpath...

Anyway, i deleted the wrong folder class that was created and all the tree containing this folder was erased !!!! .....

A quick look in the trashcan, nothing.... Eclipse does not put deleted files in the system trashcan, my blood goes off my body.... one day of coding lost because of this small bug....

So i started to test several undelete softwares. 3 hours later of scanning, my old photos or zip files came up, but no as files...

While i was starting crying my dear as code, i tried a last google search "Eclipse undelete", and here is the awaiting miracle !!! There is an option available in Eclipse !! select a folder and right mouse menu select : "Restore from Local History"

Then appear the deleted files history and you can choose which file to restore.

My coding day is restored too

Here is an annoying thing i faced today :

I used to program clips or buttons with several labels, and populate items at each label content when needed.

But in AS3, there is no way to do such things :

button_mc.gotoAndPlay("over");

button_mc.tf_over.text = "rollover text";

does not work at all.

I found a trick that used the Event.RENDER event which occurs after an enterframe : http://www.kirupa.com/forum/showthread.php?p=1914687

But i did not wanted to use an enterframe, and i found a second trick on Senocular site which uses the stage.invalidate()

The invalidate method forces the current displayObject to render itself immediately.

So to sum up the trick, we have to :

• go the new frame using gotoAndStop/gotoAndPlay
• add a listener on stage with Event.RENDER event
• create a function that will populate the new frame

So here is an example where a button needs to go to the "over" frame and fill a text which exists on this frame :

// set a clip as a button
button_mc.buttonMode = true;

// populate the rollOver frame
function onButtonRollOver(evt:Event):void{
   trace("render rollover");
   button_mc.tf_on.text = "RollOver text";
   // important : remove the listener
   stage.removeEventListener( Event.RENDER, onButtonRollOver);
}

I was quite happy to find this trick, but unfortunately there seems to be a deeper problem with the RENDER event : I managed my button with 2 listeners like above (one for rollOver, and another for rollOut).

All seems to be ok, but when I drag the mouse over and out the button quickly, the RENDER is triggered while the targeted textfield is not yet available.

SO, use this trick in your production if you don't intend to move the playhead of the displayObject too quickly. Or else, just wait for another trick....

Shame on you if you had a Atari ST or an Amiga and still not know the 8bitboy project !

The crazy man Andre Michelle stroke again with this amazing player which can play mods/xm modules from your dusty shells.

His work is simply amazing : modules transcriptions, wav cenverter, effects .... and even a nice player

The project is opensource, http://8bitboy.popforge.de/

but was developed in Flex which leads to some errors under Flash IDE.

That is why i took time to make it work by modifying some bunch of code. Thanks to samyStudio and some tricks on the web, i did it.

Basically, the player has private function and private variables, so to handle the spectrum externally, i added 2 arrays to that we can play with it :

• player.spectrum.aSpectrumValue : which returns an array with current spectrum graphical values
• player.spectrum.aInstantValue : which returns an array with real sound values

I also turned the player commands function from internal to public, so that you can control the player from your own application.

As an example of the spectrum possibilities, i made a fast blured circle effect :

sources available here

enjoy !

Here is an algorithm i had in mind for a long time, but no time to realise.

I had experienced blobs by using flash filters, but they use so much cpu that i thought about a way to do them with bezier curves.

The main idea is :

• gather many points into blobs
• find the hull (or perimeter) of each blob
• draw the hull with bezier curves

The first difficulty was to find some piece of code that will build the hull (or perimeter) of a couple of points.

I found a java code here : http://www.cs.princeton.edu/~ah/alg_anim/version2/QuickHull.html

Once the code was adapted (you can see blobs points linked by black lines in exmaple), i worked on a way to render the hull with bezier points.

I found a trick to create a larger hull built of many points that will be used for the bezier curves. The result is not as fine as i thought but i guess it's ok.

So here is an example which consists of 50 points :

Sources are available here

sorry not so much comments in code, but i think the whole thing is a bit hard. I may isolate the hull algorithm is some of you are interested in.

Here is little experiment to try some video handling with as3.

The principle is to compose the current image with let's say 50 previous recorded images from the camera, each image is used to render a horizontal part of the final image.

There are comments in the code if i'm not clear enough

the source code is available here

I was a bit ashamed to see that my site wasn't updated from july 2007....

So i took time to update projects i worked on since last year.

The fresh new projects are online !!!

http://www.lecrabe.net