Very commonly, computer programs (usually games) that have the need to simulate a shuffling of a deck of cards (or drawing a tile from a bag, etc.) will go the obvious way of putting the items in an array, and then randomize the order of the elements of the array. A common algorithm for doing that is the Fisher–Yates shuffle (you can find a suitable implementation easily by googling).

The purpose of this post, however, is not to discuss “how” to shuffle arrays. Rather, I would like to bring up the question of “why” (do it) in the first place.

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This is quite an obscure, little known, hidden-by-default feature, but the FlashDevelop IDE actually has a built-in Flash tracer. The plug-in is unfortunately not enabled by default, and new users of FlashDevelop often get frustrated wondering where to look for the output of their trace statements.

To get the tracer to work:

1) Go to Tools -> Program Settings (F10).

2) In the Plugins list on the left of the dialog box, look for FlashLogViewer and click on it.

3) On the right panel, look for the “Start Tracking” property, click on the drop down box and select “OnBuildComplete” (it is set to “Manually” by default).

The output of your trace statements are now shown in the Output Panel after you build your project.

This post is a supplement to “Serializing Bitmaps (Storing BitmapData As Raw Binary/ByteArray)”. In that article, we looked at how to convert BitmapData to a ByteArray, save that ByteArray, and re-construct the BitmapData from the saved ByteArray.

It is important to note that the technique saves the ByteArray “as is” in a flat binary file without any header or any block of metadata – this means that the file will in itself not be able to communicate its data structure and therefore, proper usage of the data requires prior knowledge of how the data has been packed (we used the first four bytes for storing the value of the width of the image). As a result, that method may be deemed as an “unorthodox” hack and unsuitable in team development.

In this post, we look at how you can employ the same basic idea while making the saved data more “consumable” by other developers.

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This post is a supplement to “Saving XML As Binary”. I neglected to mention in that post that you can, if so desired, embed the binary XML within your SWF instead of loading it during run-time. That means you still get to keep the XML externally, not as part of your application code, so that the code and data can still be kept separate and maintained more easily.

However, it must be mentioned that embedding a text XML within SWF will get it compressed as part of the SWF compression anyway. Therefore, if compression is the only motivation, don’t convert the XML to binary and embed the binary version – it does not make sense. But if you wish to do some data encryption, then the additional work may be appropriate.

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Whenever an application needs to save bitmap images to local storage or post them to a server script, a common practice is to encode the image as JPEG or PNG before sending that binary data off as the respective mimeType. However, if the intention is simply to save the bitmap image, ie to serialize the BitmapData, then converting the image to JPEG/PNG would actually be unnecessary.

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Here is how you can draw an outline on text glyphs during run-time via ActionScript. This method works with embedded as well as non-embedded fonts.

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This is Part III of our discussion on ROT128 Encryption.

Part I: “Applying ROT128 Encryption On ByteArray”
Part II: “Applying ROT128 Encryption On Embedded/Module SWFs”

In “Saving XML As Binary”, we looked at how text XML can be stored in a ByteArray object so that it can be compressed and made non-human-readable. In this post, we look at how you can integrate ROT128 into the XML-to-ByteArray-to-XML routines. Binary XML is used only as an example; you can definitely apply the same concept to other binary data.

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This post is a supplement to “Applying ROT128 Encryption On ByteArray”.

Some time back, we posted a simple technique for hiding assets and AS3 code from prying eyes by embedding one SWF within another SWF. In this post, we revisit that topic and look at how ROT128 can be used to provide an additional layer of protection.

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In this post, we will look at a very simple algorithm for weak encryption. You should not use this method for real cryptographic security. However, because it is so simple to implement, the light-weight algorithm could easily escape prying eyes and avoid being the target for decryption in the first place.

I should also clarify that the term “ROT128″ does not actually exist. The original idea comes from ROT13, a variant of the Caesar Cipher (named after Julius Caesar of ancient Rome who used it to encrypt messages, but it is not clear who first invented or started using the cipher).

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This post is a supplement to “Saving XML As Binary”.

As mentioned in the previous post, you can save XML in binary and get the benefits of compression, but doing so would make it impossible to edit the data through a text editor.

This post explores a simple tool you can create easily using Flash/ActionScript 3, a tool that will allow you (or your clients and end-users) to load, read, edit and save XML in compressed binary format. As shown below, this is a minimalist approach – feel free to beautify and/or customize it to fit your own requirements.

You can find the source code at the end of this post. The code does not use any UI component, not from Aspire UI, Flex or Flash, just plain native Flash Player classes so you can compile the AS3 class alone without any additional library.

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