To actually display a 3D object on the screen, we will need to create another class called SphereDemo. Let's take a look at the code for the SphereDemo class.

package
{

Away3D includes a number of primitive shapes that can be easily added to the scene. These primitives are covered in more detail in Chapter 2, Creating and Displaying Primitives. We will be adding the sphere primitive to the scene, which is represented by the Sphere class.

  import away3d.primitives.Sphere;

The SphereDemo class will extend Away3DTemplate, allowing us to initialize and update the Away3D engine with a minimum amount of code.

  public class SphereDemo extends Away3DTemplate
  {

In the SphereDemo constructor, we simply call the Away3DTemplate constructor with the super() statement, which will in turn initialize the Away3D engine by calling the initUI(), initEngine(), initScene(), and initListeners() functions.

    public function SphereDemo()
    {
      super();
    }

The initScene() function was deliberately left empty in the Away3DTemplate class. The SphereDemo class overrides this function to add a sphere to the scene.

    protected override function initScene():void
    {

First, we call the initScene() function from the base class.

      super.initScene();

We then create a new Sphere 3D object. The Sphere 3D object will be placed at the origin of the scene, by default. If you remember from the Away3DTemplate class, the camera is placed at (0, 0, -1000), and is oriented to look back at the scene origin. This means the Sphere 3D object will be in front of the camera when we run the application.

var sphere:Sphere = new Sphere(
{
    x: 0,
    y: 0,
    z: 500
}
);

var obj:Object = new Object();
obj.x = 0;
obj.y = 0;
obj.z = 500;
sphere = new Sphere(obj);

var sphere:Sphere = new Sphere();
sphere.x = 0;
sphere.y = 0;
sphere.z = 500;

      var sphere:Sphere = new Sphere ();

Finally, in order for the sphere to be visible it needs to be added as a child of the scene.

      scene.addChild(sphere);
    }
  }
}