Re-inventing the wheel? Definitely. Discovering that wheel for myself? Absolutely.

The code written here is procedural and we’re dealing only with two dimensions, I’m sure there are plenty of classes and aggregations of classes that handle the same thing. I started looking at some fundamental vector geometry and got to the fun part of using trig to determine directions of vectors. I coded this bit with some decent comments. It should hopefully make sense especially if you are familiar with the vocab. =)

/*define the x and y properties of a two dimensional vector representing it's coordinate displacement. The numbers here represent the coordinate style that flash uses. Or rather the the two dimensional DisplayObject properties: x and y as type Number, publicly accessible on any object that inherits from DisplayObject*/

function convertRadiansToDegrees(rad){
var degrees = rad * 180/Math.PI;
return degrees;
}


Determining the other property of a Vector namely it’s distance or length is fairly simple in the native flash environment using the Pythagorean theorem.

Note that degrees in flash look opposite of those represented in Cartesian geometry, You can convert flash degrees to Cartesian degrees by multiplying by -1. In flash Y coordinates look different from Cartesian coordinates in that flash’s Y axis is incrementing positively as you you move downward on the screen.

This makes sense if you were to imagine rotating the Cartesian plane on it’s X axis or “Pitch” 180 degrees so that it apparently directly mirrors the planes graphical direction and scalar value of before you flipped it.

Rotations are mirrored as well. Positive flash degrees rotate from 0 to 360 degrees clockwise from the positive Flash X plane. Positive Cartesian degrees increment from 0 to 360 counter-clockwise from the positive X plane.

One interesting thing that I’m seeing in at least 2d vectors is that if you multiply the same length coordinate, such as y, of a vector by -1 You will get a vector that graphically is identical to that vectors direction in comparison to a coordinate plane whose same property (in this case Y) was flipped by multiplied -1. This is great in considering that the ratios of sin cos and tan seemingly do not have to be applied differently regardless of the difference in visual direction of coordinate planes in flash and traditional Cartesian planes. Think about where 45degrees is on the flash and Cartesian coordinate planes. Multiply a vector’s y distance property by -1 just as how we get the two coordinate systems to look the same.

A vector equal in displacement or length and direction is the same as any other vector with the same length and direction regardless of it’s position One vector is also equal to the sum of any number of vectors that result in the same length and direction. In other words, you might take a round about way to wind up at your destination but regardless there is only one direct path to your final destination. Look into vector addition for the math.

The ratios of a vector’s direction with sin cos and tan are used the same regardless of plane direction. I’m assuming that sin cos and tan have a direct relationship to the relative positive and negative direction of the associated coordinate planes.

If you don’t understand what I’m saying, and would like to; Build up your knowledge in basic vector geometry, and fundamental trig. That’s what I’m doing here. I’m really glad that I’m starting to at least get a good feel for understanding Trigonometric ratios and attaining the benefits of knowing how to apply these concepts programmatically.

Oh yeah, been looking at Papervision 3D 2.0, Great White this is all your fault! =) Thought this would be a good place to do some ground work.

The implications of applying vector geometry to 3 dimensions as opposed to the two dimensional coordinates used in this example is very similar. I’m glad to finally take the due diligence necessary to understand how an object such as a matrix gives us a great way to manage and understand points and vectors their properties and relations to one another.

Afterthought:
Can you represent a vector with 4 dimensions applying a value representing time? Would that mean that the vector would now also contain the property of time as well as it’s length and directions from the previous 2 dimensions? I’m guessing that the addition of vectors with Matrixes having 4 values could represent four dimensions. If you could hypothetically imagine traveling through time and winding up at a point in your life no matter the direction length and time, and winding up at that same point given a different path you are looking at the same 4D vector. The sum of any amount of 4 dimensional vectors’ properties added in either Matrix or Row format (Here being Time, Length, and Direction) represent a single 4D vector. There’s probably a different name for 4d vectors. Let me know if I’m off base here. I’m thinking this is getting into some simple quantum physics and how the numbers might help back up the theory.

I’ve been trying to figure out how different frequencies of the sound spectrum can affect each other, and how graphical waveforms represent all of those frequencies. A friend and excellent sound engineer was giving me a couple of pointers on sound design, namely with multi band compression. A couple of days later it dawned on me how sounds in my compositions are occurring at the same time and hence interfere with each other in that they are all competing for the same air molecules to travel through.

My hypothesis is that sounds from one particular frequency are in no way decoupled from any other sounds from any other frequency if they occur at the same moment and if they significantly alter the resonation of the medium through which they travel. I say “significantly alter” in that I’m guessing that all the other frequencies that are going on all around us, that are present but not in the audible spectrum could potentially affect the air around our ears’ waveforms to some but not recognizable degree. Imagining how frequencies work within other frequencies is something that has intrigued me for quite some time.

I feel that “less” in music and sound tends to be able to make a composition seem more clear, or striking or powerful. There is a balance in too little and too much sound, all too often I’ve seen what happens when there is “too much” sound. I’m a fairly graphical thinking individual. Imagining how a moment’s audible sounds are moving together is quite fascinating.

Considering the mechanical implications of reproducing a frequency range through a single speaker makes me further question the frequencies and how their amplitudes somewhat compete amongst each other. Guess cross-overs are a pretty good idea after all.

I’m working on my first as3 class. There has been a discussion of it going on over at actionscript.org I’m questioning whether or not this should extend the MovieClip class. In any regard it works well for my needs.

In working on this class, I’ve stumbled across a very useful event “MOUSE_LEAVE” It is a constant of the Event class and not part of the MouseEvent class. It’s also worthwhile to mention that the event listener is added to the stage object once I’ve called the startDragger method, instead of in the constructor. Having the stage object listen to the event whilst instantiating my class simply does not work. I’d be interested in figuring out why this is so.

Without further ado here is the code.
package com.bowievanling{
import flash.display.MovieClip;
import flash.events.MouseEvent;
import flash.events.Event;
import flash.display.DisplayObject;
public class Dragger extends MovieClip{
private var _dragParent:Object;
public function Dragger(){
addEventListener(MouseEvent.MOUSE_DOWN, startDragger);
addEventListener(MouseEvent.MOUSE_UP, mouseStopHandle);
if(stage){
stage.addEventListener(MouseEvent.MOUSE_UP, mouseStopHandle);
}
}
private function startDragger(evt:MouseEvent):void {
//trace("dragParent = "+_dragParent);
_dragParent = evt.target.parent;
_dragParent.startDrag();
stage.addEventListener(Event.MOUSE_LEAVE, eventStopHandle);
}
private function mouseStopHandle(evt:MouseEvent){
stopDragger();
}
private function eventStopHandle(evt:Event){
stopDragger();
}
private function stopDragger(){
_dragParent.stopDrag();
}
}
}

This was a nice little exercise getting some name value pair data into an embedding flash object. swfobject 2.0 has a great new way to pass objects with your variables to your swf.

This is the javascript:

<script type="text/javascript" src="scripts/swfobject.js"></script>
<script type="text/javascript">
var flashvars = {dataFeedXML: "./data/regions_feed.xml"};
swfobject.embedSWF("swf/filename.swf", "flashDiv", "687", "486", "9.0.0", "swf/expressInstall.swf", flashvars);
</script>

I had to use the dot in the beginning of my dataFeedXML path string on my local apache installation. This may not be case depending on your server environment.

Here is the html code:

<div id="flashDiv">
<h1>Oops looks like you don't have flash!</h1>
<p><a href="http://www.adobe.com/go/getflashplayer"><img src="http://www.adobe.com/images/shared/download_buttons/get_flash_player.gif" alt="Get Adobe Flash player" /></a></p>
</div>

Here is where things get interesting if you are used to previous versions of flash. In as2 we could reference undeclared variables.

Example if we were to write this on the first frame of our main timeline: var myExternalVar:String = dataFeedXML; we would recieve the error: 1120: Access of undefined property dataFeedXML.

dataFeedXML is of the scope this, and this is [object MainTimeline]. The property [dataFeedXML] doesn’t exist at compile time. We have to access root.loaderInfo.parameters; to access the flashvars passed to our swf. The particular variable in question could be references as such: root.loaderInfo.parameters.dataFeedXML

If you would like to get all of the flash vars use:
for (var fv in root.loaderInfo.parameters) {
trace("flashvar name = "+fv);
trace("flashvar value = "+root.loaderInfo.parameters[fv]);
}