Mantain phisics while going Trough path...wut?

Troubleshooting General Help
1

Hello everybody :smiley:
I’ve got a problem,and maybe because i am a n00b, i can’t figure out how to solve it.
Ok,let’s begin:i’ve got a cube with RigidBodyControl
It’s position is over another floor (made,of course,by another cube) and in the simpleupdate method i’ve made a condition
that if the first cube (player) is over the floor,it will “float”
At this point is everything good.
But i have implemented a system that create a motionpath from the position of the cube to the point where i click on the floor
The problem is 2:
1)when the cube start travel across the path,is like it’s “losing” the phisics
2)when it finish the travel,it jumps sooo high and return
Any suggestion?here’s the code

[java]
package mygame;

import com.jme3.animation.AnimChannel;
import com.jme3.animation.AnimControl;
import com.jme3.animation.AnimEventListener;
import com.jme3.app.SimpleApplication;
import com.jme3.bullet.BulletAppState;
import com.jme3.bullet.control.RigidBodyControl;
import com.jme3.cinematic.MotionPath;
import com.jme3.cinematic.events.MotionEvent;
import com.jme3.collision.CollisionResult;
import com.jme3.collision.CollisionResults;
import com.jme3.font.BitmapText;
import com.jme3.input.ChaseCamera;
import com.jme3.input.KeyInput;
import com.jme3.input.MouseInput;
import com.jme3.input.controls.ActionListener;
import com.jme3.input.controls.AnalogListener;
import com.jme3.input.controls.KeyTrigger;
import com.jme3.input.controls.MouseButtonTrigger;
import com.jme3.light.AmbientLight;
import com.jme3.light.PointLight;
import com.jme3.light.SpotLight;
import com.jme3.material.Material;
import com.jme3.math.ColorRGBA;
import com.jme3.math.Ray;
import com.jme3.math.Vector3f;
import com.jme3.post.FilterPostProcessor;
import com.jme3.post.ssao.SSAOFilter;
import com.jme3.renderer.RenderManager;
import com.jme3.scene.Geometry;
import com.jme3.scene.Node;
import com.jme3.scene.shape.Box;

public class FsicaEnon extends SimpleApplication implements ActionListener,AnalogListener,AnimEventListener {
Node terreno = new Node();
Node giocatore = new Node();

Node personaggio = new Node();
Geometry player,terrain;
BulletAppState bas;
RigidBodyControl rgb_player,rgb_personaggio;
SpotLight spot;
PointLight lamp;
MotionPath moth;
MotionEvent moth_ev;

boolean movimento=false;

private AnimChannel chan;
private AnimControl cont;


public static void main(String[] args) {
    FsicaEnon app = new FsicaEnon();
    app.start();
}

@Override
public void simpleInitApp() {
    bas = new BulletAppState();
    stateManager.attach(bas);
    
    flyCam.setMoveSpeed(10);
    
    creauncubo("terreno",terreno,0,0,0,8,0.5f,8,true,0);//node,x,y,z,pos_x,pos_y,pos_z
    terrain=(Geometry)terreno.getChild(0);
    
    creauncubo("Giocatore", giocatore, 0, 3, 0, 1, 1, 1, false, 1);
    player=(Geometry)giocatore.getChild(0);
    
    rgb_player= new RigidBodyControl(1);
    player.addControl(rgb_player);
    bas.getPhysicsSpace().add(rgb_player);
    
    rootNode.attachChild(giocatore);
    rootNode.attachChild(terreno);
    hud();
    initKeys();
    initLight();

// initCam();
}

public void hud(){
    setDisplayStatView(false);
    guiFont = assetManager.loadFont("Interface/Fonts/Default.fnt");
    BitmapText ch = new BitmapText(guiFont, false);
    ch.setSize(guiFont.getCharSet().getRenderedSize() * 2);
    ch.setText("+"); 
    ch.setLocalTranslation( 
    settings.getWidth() / 2 - ch.getLineWidth()/2, settings.getHeight() / 2 + ch.getLineHeight()/2, 0);
    guiNode.attachChild(ch);
}
@Override
public void simpleUpdate(float tpf) {
    Ray r = new Ray(player.getWorldTranslation(), new Vector3f(0,-1,0));
    CollisionResults cs=new CollisionResults();
    terreno.collideWith(r, cs);
    float y=terrain.getLocalTranslation().y;
    float y2=player.getLocalTranslation().y;        
    if(cs.size()>0&&((y2-y)<4)&&!movimento){
        rgb_player.applyCentralForce(new Vector3f(0,20,0));
    }
    lamp.setPosition(cam.getLocation());
}

@Override
public void simpleRender(RenderManager rm) {}

public void initCam(){
    cam.setLocation(new Vector3f(player.getWorldTranslation().x+5,player.getWorldTranslation().y+5,player.getWorldTranslation().z+5));
    ChaseCamera ccam = new ChaseCamera(cam, player, inputManager);
    ccam.setSmoothMotion(false);
    ccam.setDefaultDistance(8);
    ccam.setMaxDistance(10);
    ccam.setDragToRotate(false);
}

public void initKeys(){
    inputManager.addMapping("up", new KeyTrigger(KeyInput.KEY_W));
    inputManager.addMapping("down", new KeyTrigger(KeyInput.KEY_S));
    inputManager.addMapping("left", new KeyTrigger(KeyInput.KEY_A));
    inputManager.addMapping("right", new KeyTrigger(KeyInput.KEY_D));
    inputManager.addMapping("jump", new KeyTrigger(KeyInput.KEY_SPACE));
    inputManager.addMapping("click", new MouseButtonTrigger(MouseInput.BUTTON_LEFT));
    inputManager.addMapping("r_click", new MouseButtonTrigger(MouseInput.BUTTON_RIGHT));
    //inputManager.addListener(analogListener, new String[]{"up","down","left","right"});
    inputManager.addListener(actionListener, new String[]{"jump","click","r_click"});
}

public void initLight(){
    AmbientLight al= new AmbientLight();
    al.setColor(ColorRGBA.White);
    rootNode.addLight(al);
    
    FilterPostProcessor fpp = new FilterPostProcessor(assetManager);
    viewPort.addProcessor(fpp);
    SSAOFilter ssaoFilter = new SSAOFilter(12.94f, 43.93f, 0.33f, 0.60f);
    fpp.addFilter(ssaoFilter); 

    lamp = new PointLight();
    lamp.setPosition(Vector3f.ZERO);
    lamp.setColor(ColorRGBA.White);
    rootNode.addLight(lamp); 
    
    viewPort.setBackgroundColor(new ColorRGBA(0.7f, 0.8f, 1f, 3f));
}

public void creauncubo(String name,Node nd,float x,float y,float z,float dim_x,float dim_y,float dim_z,boolean conc,int weight){
    Box nc = new Box(dim_x,dim_y,dim_z);
    Geometry gm = new Geometry("cubo",nc);
    gm.setLocalTranslation(new Vector3f(x,y,z));
    Material mt = new Material(assetManager,"Common/MatDefs/Misc/Unshaded.j3md");
    //mt.getAdditionalRenderState().setWireframe(true);
    mt.setColor("Color", ColorRGBA.randomColor());
    gm.setMaterial(mt);
    if(conc){
        RigidBodyControl rgb_tmp = new RigidBodyControl(weight);
        gm.addControl(rgb_tmp);
        bas.getPhysicsSpace().add(rgb_tmp);
    }
    nd.attachChild(gm);
}

private AnalogListener analogListener = new AnalogListener(){
    public void onAnalog(String name, float value, float tpf) {
        if(name.equals("up")){
            rgb_player.applyCentralForce(cam.getDirection());
        }
        if(name.equals("down")){
            rgb_player.applyCentralForce(cam.getDirection().negate());
        }
        if(name.equals("left")){
            rgb_player.applyCentralForce(cam.getLeft());
        }
        if(name.equals("right")){
            rgb_player.applyCentralForce(cam.getLeft().negate());
        }
    }  
};

private ActionListener actionListener = new ActionListener(){
    public void onAction(String name, boolean isPressed, float tpf) {
        if(name.equals("jump")){
            Geometry tmp = (Geometry) giocatore.getChild(0);
            Material mat = tmp.getMaterial();
            mat.setColor("Color", ColorRGBA.randomColor());
            rgb_player.applyCentralForce(new Vector3f(0,2,0));
        }
        if(name.equals("click")){
            Ray y = new Ray(cam.getLocation(),cam.getDirection());
            CollisionResults cs = new CollisionResults();
            terreno.collideWith(y, cs);
            if(cs.size()>0){
                movimento=true;
                moth=new MotionPath();
                CollisionResult cd= cs.getClosestCollision();
                moth.addWayPoint(player.getWorldTranslation());
                moth.addWayPoint(new Vector3f(cd.getContactPoint().x,player.getWorldTranslation().y,cd.getContactPoint().z));
                //moth.enableDebugShape(assetManager, rootNode);
                moth_ev=new MotionEvent(player,moth);
                moth_ev.setSpeed(2);
                moth_ev.play();
                movimento=false;
            }
        }
    }
};

public void onAction(String name, boolean isPressed, float tpf) {}

public void onAnalog(String name, float value, float tpf) {}

public void onAnimCycleDone(AnimControl control, AnimChannel channel, String animName) {}

public void onAnimChange(AnimControl control, AnimChannel channel, String animName) {}

public void crea_personaggio(){
    personaggio = (Node) assetManager.loadModel("Models/Oto/Oto.mesh.xml");
    rootNode.attachChild(personaggio);
    cont=personaggio.getControl(AnimControl.class);
    cont.addListener(this);
    chan=cont.createChannel();
    chan.setAnim("stand");
    personaggio.setLocalTranslation(0, 6, 3);
    personaggio.setLocalScale(0.5f);
    rgb_personaggio=new RigidBodyControl(1);
    personaggio.addControl(rgb_personaggio);
    bas.getPhysicsSpace().add(rgb_personaggio);
}

}

[/java]

2

motion paths arent really meant to be combined with physics objects, the motion path will directly move the spatial. what you want to do is move the physics object in the physics space, and let bullet automatically update it’s position on the scene graph.

the ability to do this backwards (modify the position on the scene graph then let it be updated in the physics space) is really for convenience in warping/teleporting objects (eg setting their initial position)

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