Thank you sir. My English is not very well,but I will try my best to let you can read...
Firstly,I can save the last not null position,I will have a try.thank you ~
Secondly, I have no mean of what size of box should I make,or just the height of box in the world space is enough.
Thirdly, what  you said is very brief and clearly.thank you sir.

Dear Moderator,thank you for respond me. But how can take some vertex to represent the 3DObject？I don't really know what the meaning of view plane....

I use jpct-ae for AR 3D rendering base on Lbs.There are two questions confused me.Could some one help me?
Now I need to check  if a AnimationGroup is showing on the android screen.If not showing can I get the Position even if it is out of Fov(instead of null..)？Because I need to make a Indicator to indicate the position of the 3DObject.
Now I have known how to transform a Point in world space to screen space. I use the following code .
SimpleVector bottomP =  Interact2D.project3D2D(cam,fb,ninja.getRoot().getCenter());//how to avoid botoomP be null,even if it is out of Camera Fov?
The question is how can I get someting like a Rect or a box or anyother useful vertex to represent the 3dObject position?

Very lucky that you can reply me so quickly~
I got it !Thank you sir,you save my time.Here is my way,hope this can help other new user that have the same question.


// The renderer class for the ImageTargets sample.
public class ImageTargetRenderer implements GLSurfaceView.Renderer
{
    private static final String LOGTAG = "ImageTargetRenderer";
    private SampleApplicationSession vuforiaAppSession;
    private ImageTargets mActivity;

    private Renderer mRenderer;
    boolean mIsActive = false;

    private World world;
    private Light sun;
    //    private Object3D cylinder;
    private AnimatedGroup animatedGroup;
    private Camera cam;
    private FrameBuffer fb;
    private float[] modelViewMat;
    private float fov;
    private float fovy;
    float  animationIndex=0;

    public ImageTargetRenderer(ImageTargets activity, SampleApplicationSession session) {
        mActivity = activity;
        vuforiaAppSession = session;

        world = new World();
        world.setAmbientLight(200, 200, 200);
        // set the following value according to your need, so the object won't be disappeared.
        world.setClippingPlanes(2.0f, 3000.0f);

        sun = new Light(world);
        sun.setIntensity(250, 250, 250);

        // Create a texture out of the icon...:-)
        if ( !TextureManager.getInstance().containsTexture("texture") ) {
            Texture texture = new Texture(BitmapHelper.rescale(BitmapHelper.convert(
                    mActivity.getResources().getDrawable(R.drawable.icon)), 64, 64));
            TextureManager.getInstance().addTexture("texture", texture);
        }
        try {
            animatedGroup = BonesIO.loadGroup(mActivity.getResources().openRawResource(R.raw.ninja_group_bones));
        } catch (IOException e) {
            e.printStackTrace();
        }
        TextureManager.getInstance().flush();
        // Create a texture out of the icon...:-)
        if ( !TextureManager.getInstance().containsTexture("ninja") ) {
            Resources res = mActivity.getResources();
//                Texture texture = new Texture(res.openRawResource(R.raw.lenaa));
            Texture texture = new Texture(res.openRawResource(R.raw.ninja_texture));
            texture.keepPixelData(true);
            TextureManager.getInstance().addTexture("ninja", texture);
        }
        for (Animated3D anim : animatedGroup){
//                anim.scale(1f);
            anim.setTexture("ninja");
            //this line not work well ,will change the positon of Object3d
//            anim.rotateX((float) Math.PI);

        }
        //I add follow two lines
        animatedGroup.getRoot().rotateX(-(float) Math.PI);
        animatedGroup.getRoot().rotateY((float) Math.PI);
        animatedGroup.addToWorld(world);
        cam = world.getCamera();


        // for older Android versions, which had massive problems with garbage collection
        MemoryHelper.compact();

    }


    // Called to draw the current frame.
    @Override
    public void onDrawFrame(GL10 gl) {
        if (!mIsActive)
            return;

        // Call our function to render content
        renderFrame();
        updateCamera();


        animationIndex += 0.0008f;
        while (animationIndex > 1)
            animationIndex -= 1;

        animatedGroup.animateSkin(animationIndex, 0);
//        }
        world.renderScene(fb);
        world.draw(fb);
        fb.display();

    }


    // Called when the surface is created or recreated.
    @Override
    public void onSurfaceCreated(GL10 gl, EGLConfig config) {
        Log.d(LOGTAG, "GLRenderer.onSurfaceCreated");

        initRendering(); // NOTE: Cocokin sama cpp - DONE

        // Call Vuforia function to (re)initialize rendering after first use
        // or after OpenGL ES context was lost (e.g. after onPause/onResume):
        vuforiaAppSession.onSurfaceCreated();
    }


    // Called when the surface changed size.
    @Override
    public void onSurfaceChanged(GL10 gl, int width, int height) {
        Log.d(LOGTAG, "GLRenderer.onSurfaceChanged");

        if (fb != null) {
            fb.dispose();
        }
        fb = new FrameBuffer(width, height);
        Config.viewportOffsetAffectsRenderTarget = true;

        updateRendering(width, height);

        // Call Vuforia function to handle render surface size changes:
        vuforiaAppSession.onSurfaceChanged(width, height);
    }


    // Function for initializing the renderer.   
    private void initRendering() {
        mRenderer = Renderer.getInstance();

        // Define clear color
        GLES20.glClearColor(0.0f, 0.0f, 0.0f, Vuforia.requiresAlpha() ? 0.0f : 1.0f);

        // Hide the Loading Dialog
        mActivity.loadingDialogHandler
                .sendEmptyMessage(LoadingDialogHandler.HIDE_LOADING_DIALOG);
    }

    private void updateRendering(int width, int height) {

        // Update screen dimensions
        vuforiaAppSession.setmScreenWidth(width);
        vuforiaAppSession.setmScreenHeight(height);

        // Reconfigure the video background
        vuforiaAppSession.configureVideoBackground();

        CameraCalibration camCalibration = com.vuforia.CameraDevice.getInstance().getCameraCalibration();
        Vec2F size = camCalibration.getSize();
        Vec2F focalLength = camCalibration.getFocalLength();
        float fovyRadians = (float) (2 * Math.atan(0.5f * size.getData()[1] / focalLength.getData()[1]));
        float fovRadians = (float) (2 * Math.atan(0.5f * size.getData()[0] / focalLength.getData()[0]));

        if (vuforiaAppSession.mIsPortrait) {
            setFovy(fovRadians);
            setFov(fovyRadians);
        } else {
            setFov(fovRadians);
            setFovy(fovyRadians);
        }

    }

    // The render function.
    private void renderFrame() {
        // clear color and depth buffer
        GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
        // get the state, and mark the beginning of a rendering section
        State state = mRenderer.begin();
        // explicitly render the video background
        mRenderer.drawVideoBackground();

        float[] modelviewArray = new float[16];
        // did we find any trackables this frame?
        for (int tIdx = 0; tIdx < state.getNumTrackableResults(); tIdx++) {
            // get the trackable
            TrackableResult result = state.getTrackableResult(tIdx);
            Trackable trackable = result.getTrackable();
            printUserData(trackable);

            Matrix44F modelViewMatrix = Tool.convertPose2GLMatrix(result.getPose());
            Matrix44F inverseMV = SampleMath.Matrix44FInverse(modelViewMatrix);
            Matrix44F invTranspMV = SampleMath.Matrix44FTranspose(inverseMV);

            modelviewArray = invTranspMV.getData();
            updateModelviewMatrix(modelviewArray);

        }
        // hide the objects when the targets are not detected
        if (state.getNumTrackableResults() == 0) {
            float m [] = {
                    1,0,0,0,
                    0,1,0,0,
                    0,0,1,0,
                    0,0,-10000,1
            };
            modelviewArray = m;
            updateModelviewMatrix(modelviewArray);
        }

        mRenderer.end();
    }


    private void printUserData(Trackable trackable) {
        String userData = (String) trackable.getUserData();
        Log.d(LOGTAG, "UserData:Retreived User Data \"" + userData + "\"");
    }

    private void updateModelviewMatrix(float mat[]) {
        modelViewMat = mat;
    }

    private void updateCamera() {
        if (modelViewMat != null) {
            float[] m = modelViewMat;

            final SimpleVector camUp;
            if (vuforiaAppSession.mIsPortrait) {
                camUp = new SimpleVector(-m[0], -m[1], -m[2]);
            } else {
                camUp = new SimpleVector(-m[4], -m[5], -m[6]);
            }

            final SimpleVector camDirection = new SimpleVector(m[8], m[9], m[10]);
            final SimpleVector camPosition = new SimpleVector(m[12], m[13], m[14]);

            cam.setOrientation(camDirection, camUp);
            camPosition.y +=100;
            camPosition.z +=100;
            cam.setPosition(camPosition);

            cam.setFOV(fov);
            cam.setYFOV(fovy);
        }
    }

    private void setFov(float fov) {
        this.fov = fov;
    }

    private void setFovy(float fovy) {
        this.fovy = fovy;
    }

}

I am a new user of jpct-ae.When I comebine ninja demo and vuforia demo I meet a little problem.The ninja animatedGroup is upside down. Just upside down and track is OK.Can some one help me? Here is my render file.(I just change very little from https://github.com/TheMaggieSimpson/Vuforia559_jPCT-AE)


public class ImageTargetRenderer implements GLSurfaceView.Renderer
{
    private static final String LOGTAG = "ImageTargetRenderer";
    private SampleApplicationSession vuforiaAppSession;
    private ImageTargets mActivity;
   
    private Renderer mRenderer;
    boolean mIsActive = false;
       
    private World world;
    private Light sun;
//    private Object3D cylinder;
    private AnimatedGroup animatedGroup;
    private Camera cam;
    private FrameBuffer fb;
    private float[] modelViewMat;
    private float fov;
private float fovy;
float  animationIndex=0;

    public ImageTargetRenderer(ImageTargets activity, SampleApplicationSession session) {
        mActivity = activity;
        vuforiaAppSession = session;
       
        world = new World();
    world.setAmbientLight(20, 20, 20);
    // set the following value according to your need, so the object won't be disappeared.
    world.setClippingPlanes(2.0f, 3000.0f);

    sun = new Light(world);
    sun.setIntensity(250, 250, 250);

    // Create a texture out of the icon...:-)
    if ( !TextureManager.getInstance().containsTexture("texture") ) {
    Texture texture = new Texture(BitmapHelper.rescale(BitmapHelper.convert(
    mActivity.getResources().getDrawable(R.drawable.icon)), 64, 64));
        TextureManager.getInstance().addTexture("texture", texture);
    }
        try {
            animatedGroup = BonesIO.loadGroup(mActivity.getResources().openRawResource(R.raw.ninja_group_bones));
        } catch (IOException e) {
            e.printStackTrace();
        }
        TextureManager.getInstance().flush();
        // Create a texture out of the icon...:-)
        if ( !TextureManager.getInstance().containsTexture("ninja") ) {
            Resources res = mActivity.getResources();
//                Texture texture = new Texture(res.openRawResource(R.raw.lenaa));
            Texture texture = new Texture(res.openRawResource(R.raw.ninja_texture));
            texture.keepPixelData(true);
            TextureManager.getInstance().addTexture("ninja", texture);
        }
        for (Animated3D anim : animatedGroup){
//                anim.scale(1f);
            anim.setTexture("ninja");
        }
        animatedGroup.addToWorld(world);
        cam = world.getCamera();


    // for older Android versions, which had massive problems with garbage collection
    MemoryHelper.compact();
       
    }
       
   
    // Called to draw the current frame.
    @Override
    public void onDrawFrame(GL10 gl) {
        if (!mIsActive)
            return;
       
        // Call our function to render content
        renderFrame();
        updateCamera();


            animationIndex += 0.0008f;
            while (animationIndex > 1)
                animationIndex -= 1;

            animatedGroup.animateSkin(animationIndex, 0);
//        }
        world.renderScene(fb);
        world.draw(fb);
        fb.display();
       
    }
   
   
    // Called when the surface is created or recreated.
    @Override
    public void onSurfaceCreated(GL10 gl, EGLConfig config) {
        Log.d(LOGTAG, "GLRenderer.onSurfaceCreated");
       
        initRendering(); // NOTE: Cocokin sama cpp - DONE
       
        // Call Vuforia function to (re)initialize rendering after first use
        // or after OpenGL ES context was lost (e.g. after onPause/onResume):
        vuforiaAppSession.onSurfaceCreated();
    }
   
   
    // Called when the surface changed size.
    @Override
    public void onSurfaceChanged(GL10 gl, int width, int height) {
        Log.d(LOGTAG, "GLRenderer.onSurfaceChanged");
                 
        if (fb != null) {
            fb.dispose();
        }
        fb = new FrameBuffer(width, height);
        Config.viewportOffsetAffectsRenderTarget = true;
       
        updateRendering(width, height);       
       
        // Call Vuforia function to handle render surface size changes:
        vuforiaAppSession.onSurfaceChanged(width, height);
    }
   
   
    // Function for initializing the renderer.   
    private void initRendering() {
        mRenderer = Renderer.getInstance();
       
    // Define clear color
        GLES20.glClearColor(0.0f, 0.0f, 0.0f, Vuforia.requiresAlpha() ? 0.0f : 1.0f);       
       
        // Hide the Loading Dialog
        mActivity.loadingDialogHandler
            .sendEmptyMessage(LoadingDialogHandler.HIDE_LOADING_DIALOG);
    }
   
    private void updateRendering(int width, int height) {
   
    // Update screen dimensions
    vuforiaAppSession.setmScreenWidth(width);
    vuforiaAppSession.setmScreenHeight(height);
   
    // Reconfigure the video background
    vuforiaAppSession.configureVideoBackground();
   
    CameraCalibration camCalibration = com.vuforia.CameraDevice.getInstance().getCameraCalibration();
    Vec2F size = camCalibration.getSize();
    Vec2F focalLength = camCalibration.getFocalLength();
    float fovyRadians = (float) (2 * Math.atan(0.5f * size.getData()[1] / focalLength.getData()[1]));
    float fovRadians = (float) (2 * Math.atan(0.5f * size.getData()[0] / focalLength.getData()[0]));
   
    if (vuforiaAppSession.mIsPortrait) {
    setFovy(fovRadians);
    setFov(fovyRadians);
    } else {
    setFov(fovRadians);
    setFovy(fovyRadians);
    }
   
    }
   
    // The render function.
    private void renderFrame() {
        // clear color and depth buffer
    GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
        // get the state, and mark the beginning of a rendering section
        State state = mRenderer.begin();
        // explicitly render the video background
        mRenderer.drawVideoBackground();       
       
        float[] modelviewArray = new float[16];
        // did we find any trackables this frame?
        for (int tIdx = 0; tIdx < state.getNumTrackableResults(); tIdx++) {
        // get the trackable
            TrackableResult result = state.getTrackableResult(tIdx);
            Trackable trackable = result.getTrackable();
            printUserData(trackable);
           
            Matrix44F modelViewMatrix = Tool.convertPose2GLMatrix(result.getPose());                     
            Matrix44F inverseMV = SampleMath.Matrix44FInverse(modelViewMatrix);           
            Matrix44F invTranspMV = SampleMath.Matrix44FTranspose(inverseMV);
           
            modelviewArray = invTranspMV.getData();
            updateModelviewMatrix(modelviewArray);
                                       
        }                     
        // hide the objects when the targets are not detected
    if (state.getNumTrackableResults() == 0) {
    float m [] = {
    1,0,0,0,
    0,1,0,0,
    0,0,1,0,
    0,0,-10000,1
    };
    modelviewArray = m;
    updateModelviewMatrix(modelviewArray);
    }   
       
        mRenderer.end();
    }
   
   
    private void printUserData(Trackable trackable) {
        String userData = (String) trackable.getUserData();
        Log.d(LOGTAG, "UserData:Retreived User Data \"" + userData + "\"");
    }
           
    private void updateModelviewMatrix(float mat[]) {
        modelViewMat = mat;
    }
       
    private void updateCamera() {
    if (modelViewMat != null) {   
    float[] m = modelViewMat;

final SimpleVector camUp;
if (vuforiaAppSession.mIsPortrait) {
camUp = new SimpleVector(-m[0], -m[1], -m[2]);
} else {
camUp = new SimpleVector(-m[4], -m[5], -m[6]);
}

final SimpleVector camDirection = new SimpleVector(m[8], m[9], m[10]);
final SimpleVector camPosition = new SimpleVector(m[12], m[13], m[14]);

cam.setOrientation(camDirection, camUp);
cam.setPosition(camPosition);

cam.setFOV(fov);
cam.setYFOV(fovy);
    }
    }
       
    private void setFov(float fov) {
this.fov = fov;
}
   
private void setFovy(float fovy) {
this.fovy = fovy;
}
   
}

Quote from: lbb19930915 on November 18, 2016, 05:27:12 AM
I have the same question.There are just a bones.jar,and how can I use it? Is there a example?please~

I now understand how wo use the commandLine.But I enter the following error. Can anybody help me?(__.mesh.xml is my mesh file)
java -classpath /Users/mac02/Desktop/studiospace/test/JpctTest/app/libs/bones.jar  raft.jpct.bones.util.JMEOgreImporter -out /Users/mac02/Desktop/jpct/che.bones -in /Users/mac02/Desktop/jpct/__.mesh.xml
Exception in thread "main" java.lang.NoClassDefFoundError: com/jmex/model/ogrexml/OgreLoader
   at raft.jpct.bones.util.JMEOgreImporter.loadGroup(JMEOgreImporter.java:109)
   at raft.jpct.bones.util.JMEOgreImporter.loadGroup(JMEOgreImporter.java:88)
   at raft.jpct.bones.util.JMEOgreImporter.run(JMEOgreImporter.java:69)
   at raft.jpct.bones.util.JMEOgreImporter.main(JMEOgreImporter.java:170)
Caused by: java.lang.ClassNotFoundException: com.jmex.model.ogrexml.OgreLoader
   at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
   at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
   at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
   at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
   ... 4 more

I have the same question.There are just a bones.jar,and how can I use it? Is there a example?please~