import javax.media.j3d.Appearance;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.Bounds;
import javax.media.j3d.Material;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.vecmath.Point3d;
import javax.vecmath.Vector3f;

import com.sun.j3d.utils.geometry.Sphere;


public class CelestialBody extends TransformGroup {

    public Transform3D movement = null;

    public final double timeScale = 0.0001f;
    public final double gravitationalConstant = 6.67384e-11; // m^3 / (kg * s^2)

    public double mass = 1.0f; // kg. Mass should never be 0!!!

    CelestialBody(float posX, float posY, float posZ) {
        // This is set for the dynamic behaviour.
        setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);

        Transform3D t3d = new Transform3D();
        t3d.setTranslation(new Vector3f(posX, posY, posZ));
        setTransform(t3d);
        setBounds(new BoundingSphere(new Point3d(0.0f, 0.0f, 0.0f), 10000.0f));

        Sphere sphere = new Sphere(1.0f, Sphere.GENERATE_NORMALS, 100, createAppearance());

        addChild(sphere);
    }

    private Appearance createAppearance() {
        Appearance appear = new Appearance();
        Material mat = new Material();
        mat.setShininess(100.0f);
        appear.setMaterial(mat);

        return appear;
    }
}