Datasheet

Part 1: Getting Started

The typical flow of such a program involves first initializing the program and then using a listener to

loop through a scripted animation routine. The whole process can be divided into three parts: initialize,

listen and loop:

Initialize: Steps 1.3

Initializing an AS3 program can be a little overwhelming at first. The question that most people ask is

how do I know what imports to bring in? There is no magical pool of knowledge that can help you. It

just takes experience (or reading the documentation, or paying attention to syntax). As you work with

the different Flash and Papervision3D methods you ’ ll become experienced in spotting classes that need

to be imported. For example, if you ’ re creating a Wii game, it ’ s obvious that you ’ ll need to import some

Wii classes.

But, which ones? It depends on which methods you ’ re using to create your program. From experience,

you ’ ll begin to recognize and associate the right classes with their methods. Or better yet, Flex builder

has an auto - complete that automatically adds the classes you need upon auto - completion of a method.

In the example below, you create a ball sprite, so it makes sense that you ’ ll need to import the Sprite

class. After importing the Sprite class, you initialize the position and angle of the ball and then set your

focal length (from experience 300 works well for this example). Then in step 3, you create your ball, give

it a color and set it on the stage using the

addChild method.

1. Start by importing the Sprite class; this is where you ’ re going to draw a ball that you will

animate in 3D.

import flash.display.Sprite;//imports sprite class

2. Next declare your variable ’ s zposition, angle, and focal length.

var zposition:Number = 0;//z position

var myAngle:Number =0;//Angle of ball

var fl:Number = 300; //focal length

3. Next create your ball and add it to the stage.

var ball:Sprite = new Sprite();//instantiates ball sprite

ball.graphics.beginFill(0xFF0000);//Assigns a ball color

ball.graphics.drawCircle(0, 0, 40);//draws your ball at (0,0)

ball.graphics.endFill();//ends the fill

addChild(ball);//adds the ball to the stage

Listen: Step 4

In AS3, the event architecture is bigger, better, and badder (in a good way). Written from the ground up,

it ’ s fast, powerful, and easy to use. It incorporates listener objects to listen for events. Since event

listeners all work the same way, once you understand how to use one of them you understand them all.

This is how they work:

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