Java3d helicopter

Question

Hello people,
I am at the end of my tether with Java3d, i've just spent an entire day trying to get a simple helicopter working using boxes and the rotation interpolator. I simply can't get it together.. I've tried loads of examples but its just impossible!
Would someone experienced be willing to put together a simple helicopter for me (I'm sure it will only take someone experienced a matter of minutes). I just want to learn how to do it, then I'm going to re-write it so that there is no way I cant understand it! I would really appreciate if someone could do this for me, I'm only 14 and struggling with this, but i really love java3d!
thanks if you can help me!
Andy

Answer 1

Ok thanks guys, here is my code.
Since I wrote the last post I have managed to get it working at least a bit. Below i s the code for my Helicopter class, which has a method to return a helicopter TransformGroup. I then add this into my scene. The bits I need help with are:
1. I have managed to make the main rotor spin using rotationInterpolator, but I now need to make a tail rotor. How do I "rotate" my rotor TransformGroup by 90 degrees so that it rotatates perpendicular to the main rotor ??
2. I need to make the helicopter "fly" somewhere. What would be the best way of doing that?? ie. it needs to take off and move across the scene.
Any help is very much appreciated.
Thanks
* Helicopter.java
* Created on 06 August 2006, 15:46
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
package newhelicopter;
import javax.media.j3d.Appearance;
import javax.media.j3d.Material;
import javax.media.j3d.Node;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.vecmath.Color3f;
import javax.vecmath.Point3d;
import javax.vecmath.Vector3f;
import com.sun.j3d.utils.geometry.Box;
import com.sun.j3d.utils.geometry.Cylinder;
import javax.media.j3d.*;
* @author Andy
public class Helicopter {
    /** Creates a new instance of Helicopter */
    public Helicopter()
        buildHelicopter();
    public Node buildHelicopter()
        // define colour charecteristics
        Color3f emissiveColour = new Color3f(0.0f, 0.0f, 0.0f);
        Color3f specularColour = new Color3f(0.5f, 0.5f, 0.5f);
        float shininess = 100.0f;
        // create appearance for the helicopter
        Appearance helicopterApp = new Appearance();
        Color3f heliColour = new Color3f(0.5f, 0.0f, 0.0f);
        helicopterApp.setMaterial(new Material(heliColour, emissiveColour,
            heliColour, specularColour, shininess));
        //Create a box that is the cockpit
        Box cockpit = new Box(0.7f, 0.7f, 0.5f,helicopterApp);
        //Create a group that will be the root of the helicopter
        TransformGroup helicopter = new TransformGroup();
        //Add the cockpit to the helicopter group
        helicopter.addChild(cockpit);
        //Create a box to be the tail
        Box tail = new Box(2.0f, 0.2f, 0.2f, helicopterApp);
        //Create the transform and transform group that will position
        // tail behind the cockpit
        Transform3D tailXfm = new Transform3D();
        tailXfm.set(new Vector3f(2.0f, 0.5f, 0.0f));
        TransformGroup tailXfmGrp = new TransformGroup(tailXfm);
        //Add the roof to the roof transform group
        tailXfmGrp.addChild(tail);
        //Add the tail group to the helicopter
        helicopter.addChild(tailXfmGrp);
        // Create the skids
        // Create Skid no.1
        Box skid1 = new Box(1.5f, 0.1f, 0.1f, helicopterApp);
        Transform3D skidXfm = new Transform3D();
        skidXfm.set(new Vector3f(0.3f, -0.7f, 0.39f));
        TransformGroup skidXfmGrp = new TransformGroup(skidXfm);
        //Add the skid to the skid Transform Group
        skidXfmGrp.addChild(skid1);
        //Add the skid group to the helicopter
        helicopter.addChild(skidXfmGrp);
        // Create Skid no.2
        Box skid2 = new Box(1.5f, 0.1f, 0.1f, helicopterApp);
        Transform3D skid2Xfm = new Transform3D();
        skid2Xfm.set(new Vector3f(0.3f, -0.7f, -0.39f));
        TransformGroup skid2XfmGrp = new TransformGroup(skid2Xfm);
        //Add the skid to the skid transform group
        skid2XfmGrp.addChild(skid2);
        //Add the skid group to the helicopter
        helicopter.addChild(skid2XfmGrp);
        // Create the tail fin
        Box fin = new Box(0.2f, 0.8f, 0.05f, helicopterApp);
        Transform3D finXfm = new Transform3D();
        finXfm.set(new Vector3f(3.5f, 0.7f, -0.0f));
        TransformGroup finXfmGrp = new TransformGroup(finXfm);
        //Add the fin to the fin transform group
        finXfmGrp.addChild(fin);
        //Add the fin group to the helicopter
        helicopter.addChild(finXfmGrp);
        // rotor cylinder
        Cylinder rotCylinder = new Cylinder(0.1f, 1.0f, helicopterApp);
        Transform3D rotCylinderXfm = new Transform3D();
        rotCylinderXfm.set(new Vector3f(0.0f, 0.5f, -0.0f));
        TransformGroup rotCylinderXfmGrp = new TransformGroup(rotCylinderXfm);
        rotCylinderXfmGrp.addChild(rotCylinder);
        helicopter.addChild(rotCylinderXfmGrp);
        // blades
        // create a transform group for the main rotor
        TransformGroup mainRotor = new TransformGroup();
        // create a box for the first blade
        Box blade1 = new Box(0.05f, 0.05f, 3.0f, helicopterApp);
        mainRotor.addChild(createBlade(blade1));
        // create box for second blade
        Box blade2 = new Box(3.0f, 0.05f, 0.05f, helicopterApp);
        mainRotor.addChild(createBlade(blade2));
        // add main rotor to helicopter group
        helicopter.addChild(mainRotor);
        // do rotation
        mainRotor.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        Transform3D rotateblades = new Transform3D();
        Alpha rotationAlpha = new Alpha(-1, 1000);
        RotationInterpolator rotator =
            new RotationInterpolator(rotationAlpha, mainRotor, rotateblades,
                                         0.0f, (float) Math.PI*2.0f);
        rotator.setTransformAxis(rotateblades);
        BoundingSphere bounds =
            new BoundingSphere(new Point3d(0.0,0.0,0.0), 100.0);
        rotator.setSchedulingBounds(bounds);
        helicopter.addChild(rotator);
        return helicopter;
    private TransformGroup createBlade(Box box)
        Box blade1 = box;
        Transform3D blade1Xfm = new Transform3D();
        blade1Xfm.set(new Vector3f(-0.0f, 1.0f, 0.0f));
        TransformGroup blade1XfmGrp = new TransformGroup(blade1Xfm);
        //Add the blade to the blade transform group
        blade1XfmGrp.addChild(blade1);
        // return the blade TransformGroup
        return blade1XfmGrp;
}