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Archive for the ‘Flash’ Category

Converting images to black and white (Greyscale) with the ActionScript ColorMatrixFilter

without comments

Creating greyscale images with ActionScripts ColorMatrixFilter is easy to do. If you want to preview the settings you can use the following tool.

You can also load any external image into it and play with the Matrix settings.

The code is automatically saved to your clipboard when you click on the output textField. You can simply paste it into your own project and add the filter to your own DisplayObject like this:

myObject.filters = [colorMatrixFilter];

This movie requires Flash Player 9

Written by bjornson

January 31st, 2011 at 5:34 pm

Rotate dynamic system fonts with Flash Player 9

with one comment

Using Flash player 10 lets us use the rotationZ paramter of a TextField. But of course some clients require us actionscript developers to support the older player version as well.

An easy way to get around this problem is to draw the TextField into a Bitmap.  I use my own TextUtils class with a static method like this:

public static function convertTextFieldToBitmap(textField : TextField) : Bitmap

    var bitmapData : BitmapData = new BitmapData(textField.width,     textField.height, true, 0x00000000);
    var bitmap : Bitmap = new Bitmap(bitmapData);
    bitmap.smoothing = true;
    return bitmap;

So rotating and fading the TextField is no problem anymore, also the scaling works much smoother:

This movie requires Flash Player 9

Written by bjornson

March 25th, 2010 at 6:08 pm

Posted in AS3,Flash,TextField

AS3 + JavaScript = Resizable SWF in HTML

with 8 comments

I recently needed to resize an swf dynamically within an HTML document and could decided to combine JavaScript with AS3. So here is my solution in three simple steps:

  1. I wrote a simple JavaScript file that allows resizing of elements in an animated fashion.
  2. I embedded the swf in the HTML file in a <div> container with the style attribute “overflow:hidden;” and an id called “swf_container”.
  3. To ensure the desired effect I added stage.scaleMode = StageScaleMode.NO_SCALE; stage.align = StageAlign.TOP_LEFT;
  4. Now I added a button in the Flash file that caused navigateToURL(new URLRequest(“JavaScript:sizeById(‘swf_container’,500,150,5)”), “_self”); and with this calling the JavaScript function and resizing itself.

If you want to try this yourself you can download the JavaScript file sizebyid.js and recreate what I did with it or download the whole including the -.Fla, the -.swf, the -.js and the -.html file.

Of course you can try it out first:

Click the arrow in the top left corner to toggle sizes of the sample.

You can also use the following html form that calls the same JavaScript function

px width
px height
steps (fewer steps=faster)

Written by bjornson

November 5th, 2008 at 7:41 pm

Mental rotation training

with 48 comments

With this application you can train or simply test your mental rotation skills.  One of the few skills that supposedly show a real difference between men and women as well as between students of natural sciences and students of the arts. But the ability to improve, especially a poor skill, has been shown.

So try it out, after 10 exercises you will see your results.

This movie requires Flash Player 9

This movie requires Flash Player 9

Written by bjornson

September 22nd, 2008 at 8:22 pm

Air volume under water – Flash dive simulation

without comments

This application demonstrates the effect of pressure changes when diving:

This movie requires Flash Player 9

Written by bjornson

September 14th, 2008 at 8:03 pm

Posted in Diving,Flash,Physics

Visualisation of heuristics to solve the Travelling Salesman Problem (TSP) in Flash

with 14 comments

This little Flash application implements four heuristics to solve the Travelling Salesman Problem:

This movie requires Flash Player 9

How to use this application:

Type in the number of nodes and press build to set them up randomly (now max. 300 nodes).

Then you can test the different heuristics by clicking on the buttons in the top area. To hide a solution you can click the button again.

To set the nodes up differently, press build again.

NEW functionalities: Now you can edit the nodes and add new ones. Snap to grid and let the application show each step of the process.

Please comment if you are interested in some additional functionalities.

Download the AS3 Class now here. It is licensed under the Creative Commons Attribution 3.0 License. This allows you to use this class in personal and commercial products but you need to leave my name and link in the class, which is actually not seen by anyone after you publish the file. It would be nice to receive an html link, but it is not required.

To use this class do the following:

Unzip the class into the your class root folder (usually you can use the folder your .FLA file resides in). In your FLA import the class, create an object of the TSP class with an adjacency matrix. Call one of the four heuristics to receive a route array. Add the withHistory flag as true to receive the unfinished routes as well.

  1. import bjornson.Algos.TSP;
  2. var myTSP:TSP = new TSP(matrix);
  3. var nextNeighbour:Array = myTSP.returnNextNeighbour();
  4. var nearestInsertion:Array = myTSP.returnNearestInsertion();
  5. var farthestInsertion:Array = myTSP.returnFarthestInsertion();
  6. var cheapestInsertion:Array = myTSP.returnCheapestInsertion();

Now you can use the found path in any way you like. For example simply trace one:

trace(“Route found by cheapest insertion heuristic: “+cheapestInsertion.toString());

An adjacency matrix is simply a two-dimensional array containing the distances from each node to every other node. For example a small matrix containing only three nodes can look like this:

var matrix:Array = new Array( new Array( 0 , 1 , 2 ), new Array( 1,  0 , 3 ), new Array( 2 , 3 , 0 ));

At the moment only symmetric matrices can be used.

Written by bjornson

September 12th, 2008 at 8:41 am

A simple Magnifying Class for AS3

with 6 comments

It has been a while that I first programmed a magnifier glass in Actionscrtip 2. But since several friends asked over time how to do it I rewrote it in AS 3.

You can download the entire class for free here:

There are no license attachments whatsoever. So you can modify it, reuse it, sell it, whatever you like. But of course I would like to receive some feedback. You can also place links in the comments here to your site if you used this class.

The main important part is the following calculation:


First the image is loaded twice and then it positions the image that is only partially visible in the right spot over the smaller image so that it seems to be the same image.

This movie requires Flash Player 9

To include the class in your own project all you need to is:

  1. unzip into the same directory your FLA-file is in
  2. write code similar to this in your actions dialogue of your FLA (this is the very minimum you need):
  3. import bjornson.Magnify.Magnify;
    var m:Magnify = new Magnify(“a.jpg”); //this should be a relative path to a .jpg or .png
  4. Publish the file, done!
You can also specify more to customise the magnifier:
the variables are
  1. scr:String – this is the relative path to your image
  2. w:Number – this is the maximum width of the preview image
  3. h:Number – this is the maximum height of the preview image (it will be adjusted automatically to fit while keeping the correct aspect ratio)
  4. s:Boolean – this is to switch from a rectangular magnifier to a round magnifier
  5. r:Number – this is the radius of a round magnifier or the height of a rectangular magnifier
  6. rw:Number – this is the width of a rectangular magnifier
  7. m:Boolean – this defines if the Mouse-Pointer is visible when it moves over the image or not
So you could use it with the maximum amount of customisation like this:
var m:Magnify = new Magnify(“a.jpg”,600,400,false,50,50,false);
and it would create a preview picture from a.jpg with the maximum dimensions of 600×400 with a rectangular magnifying glass of 50×50 pixels and the mouse would not be visible when it moves over the image.
before adding it to the stage or any MovieClip on the stage you can position it more like this:
//and then add it:
This would add the magnifier to the stage at x:y 50:100.

Written by bjornson

September 11th, 2008 at 6:05 pm