upgrade AS2.0 swarm to AS3.0

[chluaid]

<a href="http://www.biteycastle.com/brackenwood/titles.swf" target="_blank">http://www.biteycastle.com/brackenwood/titles.swf</a>
Hey guys, I got an email recently from someone trying to implement the swarm component that Sham built for Prowlies at the River, waaaay back when he also built the first vCam. It doesn't work in an AS3.0 document so could any of our geniuses'es's take a crack at converting it? It's been such a useful component in the past that I reckon it needs to be in every Flash animator's toolbox alongside the vCam.

It's a component that is controlled through the Component Inspector panel and duplicates a sprite movieclip from the library to create the swarm. Here's a screenshot:



And here's Sham's original AS2.0 code from inside the component:

Code: (AS2.0 Swarm Code by Sham Bhangal)

function flyInit():Void {
this.speedX = Math.random()*speed;
this.speedY = Math.random()*speed;
this.onEnterFrame = flyMove;
}
function flyMove():Void {
this._x += this.speedX;
this._y += this.speedY;
if (Math.abs(this._x-sX)>sWidth) {
this.speedX = -this.speedX;
this._x = this._x+this.speedX;
}
if (Math.abs(this._y-sY)>sHeight) {
this.speedY = -this.speedY;
this._y = this._y+this.speedY;
}
if (Math.random()<jitter) {
this.speedX = Math.random()*speed-speed/2;
this.speedY = Math.random()*speed-speed/2;
}
}
function flyDie():Void {
for (var i = 0; i<numFlies; i++) {
var fly:MovieClip = _parent["fly"+i];
fly.removeMovieClip();
}
}
var sWidth:Number = this._width/2;
var sHeight:Number = this._height/2;
var sX:Number = this._x;
var sY:Number = this._y;
for (var i = 0; i<numFlies; i++) {
var fly:MovieClip = _parent.attachMovie("fly", "fly"+i, _parent.getNextHighestDepth());
fly._x = sX+(Math.random()*sWidth*2)-sWidth;
fly._y = sY+(Math.random()*sHeight*2)-sHeight;
fly.onEnterFrame = flyInit;
}
this._visible = false;
this.onUnload = flyDie;

[Jaehl]

kapow!

Code removed due to an unexpected amount of FAIL.

[chluaid]

Jaehl, you are an absolute Actionscript juggernaut. A coding god in this community of code-fearing creative types! Thanks (yet again) mate

[Snowman]

That was so fast...

[chluaid]

Hey Jaehl, got a few errors when I tried to use the component. Here's the log:

Code:

**Error** Symbol 'swarmEnvelope', Layer 'actions', Frame 1, Line 13: 1120: Access of undefined property jitter.
     if (Math.random()<jitter) {

**Error** Symbol 'swarmEnvelope', Layer 'actions', Frame 1, Line 14: 1120: Access of undefined property speed.
     flies[i].speedX = Math.random()*speed-speed/2;

**Error** Symbol 'swarmEnvelope', Layer 'actions', Frame 1, Line 14: 1120: Access of undefined property speed.
     flies[i].speedX = Math.random()*speed-speed/2;

**Error** Symbol 'swarmEnvelope', Layer 'actions', Frame 1, Line 15: 1120: Access of undefined property speed.
     flies[i].speedY = Math.random()*speed-speed/2;

**Error** Symbol 'swarmEnvelope', Layer 'actions', Frame 1, Line 15: 1120: Access of undefined property speed.
     flies[i].speedY = Math.random()*speed-speed/2;

**Error** Symbol 'swarmEnvelope', Layer 'actions', Frame 1, Line 33: 1120: Access of undefined property speed.
     flies[i].speedX = Math.random()*speed;

**Error** Symbol 'swarmEnvelope', Layer 'actions', Frame 1, Line 34: 1120: Access of undefined property speed.
     flies[i].speedY = Math.random()*speed;

**Error** Symbol 'swarmEnvelope', Layer 'actions', Frame 1, Line 29: 1120: Access of undefined property numFlies.
     for (var i = 0; i<numFlies; i++) {

Total ActionScript Errors: 8,  Reported Errors: 8

Any thoughts? The code is inside a Swarm Envelope component (screenie in first post), and the numbers are tweaked via the component inspector.

[ASP]

Hehehe...

Jaehl: KAPOW! Too fast. Kicked all your asses. No, Chluaid, no need to thank me, just doin' what I do best...

Chluaid: it didn't work...

Man I love this forum

[Jaehl]

Hmm, it seems to not be finding the component parameters. Lame. I guess AS3 handles components differently. Now I gotta find out how components work in AS3.

Edit: Okay, it turns out AS3 components use external class files. I'll put up a fixed version soon.

[chluaid]

no rush no pressure mate. Always grateful for your help

[Jaehl]

Okay, Let's try that again.

[chluaid]

perfect! So that class file must be in the same directory as any FLA in which the component is used?
Makes sense
Legend! Thanks again man, I'll add this to the tutorials and resources thread first thing tomorrow.

[Jaehl]

perfect! So that class file must be in the same directory as any FLA in which the component is used?
Makes sense

Yeah, bit of a pain, really. With AS2 you could just right click a movieclip and give it some parameters. With AS3 you have to create a separate class file, and then mess about linking it to the movieclip.

[chluaid]

Yeah that's a pain but no real biggie for an ultra simple implementation like this. I guess it's the most efficient way of working with reusable code blocks from a library of class files huh?

[supermoose]

I cleaned it up a bit.

The code never removes its listeners from the stage.  Flash doesnt do that automatically, in case the listeners would affect something more than the one object deleted.  Depending on how many swarms are being used, how many flies are in each, etc. it would most likely lag slower computers, because every time a future frame was entered, it would still try to move it's old invisible swarm of flies.  This should help improve the speed of any .swf using the component.  Let me know if you like/dont like.  Also, this is a pretty simple script, I can comment it up for future use, if you would like.

Code:

       private function flyDie(event:Event):void {
           this.removeEventListener(Event.ENTER_FRAME,flyMove);
           this.removeEventListener(Event.REMOVED_FROM_STAGE,flyDie);
           for (var i = 0; i<flies.length; i++) {
               parent.removeChild(flies[i]);
           }
       }

[Jaehl]

If the event listeners were registered to the stage (i.e. stage.addEventListener) then it would be a good idea to remove them, but as these ones are registered to the component, they stop existing when it's removed from the stage, so you don't have to worry about removing them manually.

[supermoose]

ah.  righto then, carry on.