Overview

To find the distance of any two points on an axis is easy, just subtract them. But what about when you have to find the distance of something not on the axis (a diagonal)? Find the distance between any two points with the Pythagorean theorem. This is an old problem we can look to history and find the Pythagorean theorem and Pythagoras, the Greek we’ve named this after. His theorem states that ‘In any right triangle, the area of the square whose side is the hypotenuse (the side opposite the right angle) is equal to the sum of the areas of the squares whose sides are the two legs (the two sides that meet at a right angle).’

You may remember it as the formula you memorized in geometry or algebra class ‘a squared plus b squared equals c squared’

Okay, but how does that help in flash? You want to find the distance between point

and point

. Well

would be the distance between the two points. We know the formula, solving for c.

.

is the square root function, so

.

computes and returns the square root of

.

is the power function, so

(4 squared).

computes and returns

to the power of

.

You say I remember using this for triangles and stuff, I just want to know the distance between two points, there’s no triangles.
Well, there actually is a triangle we can draw. Go from your first, along an axis (this makes one side), and the other point, along the other axis (this is another side), and you’ll see that the distance you’re looking for is the third side of the triangle (the hypotenuse).

Example

Here’s a quick interactive flash file to show the idea.

Actionscript

Download

As usual, here’s the source flash file (flash 8 compatible) to take a look: distance.fla

Overview:

Using what I learned with the Actionscript Javascript Communication Tutorial, and pushing it a little further I’ve set up this example of how flash renders html and css. This is basically a wysiwyg (What you see is what you get) html editor! Natively flash only handles some html and css. Many people have enhanced it’s capabilities with projects and Classes, but I made this to show what is accepted by default as far as html and css is concerned. I know there are specs and many lists about what will work, but to me the best way to know if my code will work is to try and see…
I’ve made this app so if I have a question, I just paste in my html/css and send it to the swf to see it rendered live. This saved me a few headaches, so I thought other might enjoy it as well… So here it is.

Example:

Render your own html and or css in flash. htmlToFlash.html
Here is the flash rendering of some dummy text as html with css applied


Here’s the html interface where I paste in the html and css.

Each supported css property has a corresponding actionscript property, but the naming convention is a little different for css in actionscript. Each actionscript property name is derived from the corresponding CSS property name; the hyphen is omitted and the subsequent character is capitalized. So for example: ‘font-weight’ becomes ‘fontWeight’.

Download:

Here’s the open source files if you want to get your hands dirty.

Let me know if you improve this or even have any questions about it!

Again, note there are only certain HTMl and CSS supported by flash, follow the links for more info.
HTML supported by Flash and CSS supported by Flash

Gives feel of perspective and depth by reacting to mouse movements. The effect is parallax, read more…
The city images are very choppy and ugly, I know, it’s just a test.

Sample Actionscript. This in on one of the buildings which are separate movie clips. Adjust the equation for different effect.
The basic formula is as follows: this._x = _root._xmouse / (speed) + transform

Update: Here’s a similar effect achieved by just negating the relation between the mouse and the building movie clips.

Download Source Fla File

Overview:

Using ExternalInterface.addCallback() we can expose an actionscript function and make it available to javascript. This would be helpful to have your webpage with embedded flash communicate to your flash swf file and even control it with javascript! Say we wanted to have buttons in the html page that would control an object in the flash. Communication is a two-way road so wouldn’t it be great to be able to go the other way as well, you can! That is the main function of ExternalInterface! In this example/tutorial I will explain both directions of communication with flash and javascript! Communication between flash and javascript isn’t just a myth or mystery!

Steps:

1. Be sure to import flash.external.*;
2. Set up the javascript to actionscript lane of your communication road. (ExternalInterface.addCallback(methodName, instance, method);)
3. Write your javascript function.
4. Set up the actionscript to javascript lane. (ExternalInterface.call(functionNameInJavascript);)

We will follow the text’s journey on our road of communication…

The One way: I type in ‘Johnny Appleseed’ in the html text box and press the Send Text To Flash button. The onclick javascript event finds the flash element and calls it’s function (sendTextFromHtml) and then clears the text in the html box. This function has been set up and is exposed to javascript (in actionscript lines 4-7) with the methodName ‘sendTextFromHtml’ while the method it calls is recieveTextFromHtml() in the actionscript. So ‘Johnny Appleseed’ is received as the parameter of the recieveTextFromHtml() function and is assigned to the text of the theText text box.

And back: Now I delete ‘Johnny Appleseed’ since he’s only a fable and enter ‘Paul Bunyan’ in the swf text box and press the Send From Flash to Javascript button. This calls the onRelease function associated with this button. ExternalInterface.call calls the ‘recieveTextFromFlash’ function in the javascript of the page and passes ‘Paul Bunyan’ as the parameter. The javascript function finds the html text box using getElementById() and assigns the parameter to the value of that text box!

This technique will even work if you’re not sending folklore character down the road.

Example:

View the live example here: ActionscriptJavascriptCommunication.html

NEW live example with swfobject2 works in IE! ActionscriptJavascriptCommunication2.html

Actionscript:

Javascript:

HTML: view Source of sample page

Download:

Download all source files (.fla, .html, .swf): ActionscriptJavascriptCommunication.zip

The results are in and the requested topic is “Integrate Google Analytics into Flash.” The poll has been reset and is ready to recieve your post requests, so keep voting! It’s located in the side bar!

Overview:

Tracking your visitors and attempting to better understand them is a large part of even having content on the web. Since the days of visitor counters displayed proudly on every site, along with dozens of animated gifs to the days when site were designed solely with efficiency and conversion in mind. There are many services that will do this for a fee and other that will do it for free. A popular free web analytics tool is provided by Google. Google Analytics is started by including JavaScript on each page the user wishes to track. This JavaScript loads larger files from the Google webserver and then sets variables with the user’s account number. This JavaScript is used to track and log page views and visitors interaction with the site. This post discusses what to do if your site includes a lot of interactive flash elements you wish to track as well. With the little Google has published related to this(New Code, Old Code), I’ve tried to fill in.
Note: This explains how to set up to track flash events as page views, which does have a drawback- it inflates your pageviews in the analytics and in turn may skew your data. Il’l beposting again soon about how to use then new event tracking, which would track flash events not as pageviews, but as events and thus not inflate the page view count.

Steps:

1. If you haven’t already, install Google Analytics on your site. (Note that your analytics tracking code must be placed on the page above the flash call(s) to _trackPageview or urchinTracker)
2. Determine which events in flash you want to track.
3. Place in the external.interface code in your actionscript at the specific event(s).
4. Watch the events get logged in you Google Analytics Reports!

Example:

Here’s a simple example, say you want to track how many times an object is clicked or dragged by a user or how many times it bounces (something that could be tracked but doesn’t necessarily have any required user interaction). In this example flash file I have a ball which bounces off the walls and users can click to drag and even throw it, press the spacebar to create more balls and toggle the gravity on and off with the arrow keys (up is weightlessness, and down is gravity). Each of these events has code to communicate with Google Analytics JavaScript and track the events. I made my own function to call the google analytics code. Do I hear “but sometimes I want to use the new version of Google analytics, and sometimes I want to use the old one…” Have no fear, this function works for either one, or even both. If you’re not using the newer code the calls to the functions in the new code (pageTracker._trackPageview()) will be ignored and vice versa, if you are using the new code, then the calls to the functions in the old code (urchinTracker()) will be ignored, since the functions are not defined. You can track virtually anything with this method. I’ve exaggerated greatly in this example- just to show the variety of different ways this can be used. You might want to make certain the things you track will be useful and relevant for you.

Here is the swf file, I’ve added a text box that will print all actions that are logged to Google Analytics

track Google Analytics actionscript function

Calls to Google Analytics actionscript function

Download:

IntegrateGoogleAnalytics.zip

Update:

Here is a screenshot of my Google Analytics Top Content after I search for “pageTracker/IntegrateGoogleAnalytics” (because I’m using the new code version, if I were using the old version I’d search for “urchin/IntegrateGoogleAnalytics”). This just shows that every event was logged to Google Analytics. This screenshot was taken mere hours after this post published.

New Event Tracking technique tutorial rather than posting each event you want to track in flash as a pageview it can be a specific event!