java - jBullet相机 "Holder"不动

Question

我正在使用 jBullet 和 OpenGL 来创建一个基本的游戏引擎。我创建了两个名为 ObjectSurface 和 ObjectEntity 的类。基本上，ObjectSurface 没有质量，因此它们不会移动，而 ObjectEntity 可以通过碰撞或重力移动。

我使用名为 cameraHolder 的 ObjectEntity 对象创建了一个相机，以便它可以掉落并发生碰撞等。

问题在于，当按下特定的 WASD 键时，cameraHolder 应该会移动，但它只移动一个单位，并且不会移动别再动了。释放按钮后，它会向相反方向移动一个单位，以便您位于同一位置。在 cameraHolder 移动后，相机的 XYZ 将设置为 cameraHolder 的 XYZ 坐标。

但是，该运动适用于由于重力而下落的 jBullet 引起的运动。

当我不使用 jBullet 更新时，cameraHolder 会正常移动。所以问题应该出在 jBullet 更新上。 我将在代码中展示这一点。

问题:为什么按下特定的 WASD 按钮时，cameraHolder 仅移动 1 个单位然后又返回？

以下是 Camera.java 类中的运动代码:

public void move(float amount, float direction) {

if(!still){
    if (direction == MOVE_BACKWARD) {
        //MOVE BACKWARDS (CODE NOT NEEDED, WORKS WITHOUT CAMERA CARRIER)
        }

        if (direction == MOVE_FORWARD) {
        //MOVE FORWARD
        }

        if (direction == MOVE_LEFT) {
        //MOVE LEFT
        }

        if (direction == MOVE_RIGHT) {
        //MOVE RIGHT
        }
    }
}

public void carryCamera() {
    if(!still){
    x = cameraHolder.pos.x;
    y = cameraHolder.pos.y;
    z = cameraHolder.pos.z;
    }
}

以下是ObjectEntity的创建方式:

private void createShape() {
    DefaultMotionState fallMotionState = new DefaultMotionState(new Transform(new Matrix4f(new Quat4f(0, 0, 0, 1), new Vector3f(pos.x, pos.y, pos.z), 1.0f)));
    Vector3f fallInertia = new Vector3f(0,0,0); 
    shape.calculateLocalInertia(mass,fallInertia); 
    RigidBodyConstructionInfo fallRigidBodyCI = new RigidBodyConstructionInfo(mass,fallMotionState,shape,fallInertia); 
    body = new RigidBody(fallRigidBodyCI); 
    Engine.getDynamicsWorld().addRigidBody(body); 
}

以下是物理世界的创建方式:

private static void initPhysics() {
    BroadphaseInterface broadphase = new DbvtBroadphase();
    DefaultCollisionConfiguration collisionConfiguration = new DefaultCollisionConfiguration();
    CollisionDispatcher dispatcher = new CollisionDispatcher(collisionConfiguration);
    SequentialImpulseConstraintSolver solver = new SequentialImpulseConstraintSolver();
    dynamicsWorld = new DiscreteDynamicsWorld(dispatcher, broadphase, solver, collisionConfiguration);
    dynamicsWorld.setGravity(Game.gravity);
}

如何获取输入和更新物理(这部分中有可疑代码):

public static Vector3f gravity = new Vector3f(0, -10, 0); //GRAVITY
private ArrayList<Object> objects; //ALL THE OBJECTS IN THE GAME (CAMERAHOLDER IS IN HERE)

        //GETTING INPUT, USING move() METHOD IN CAMERA CLASS TO MOVE HOLDER.
public void getInput() {

    if (Keyboard.isKeyDown(Keyboard.KEY_LCONTROL))
        speedMultiplier = 3;

    if (Keyboard.isKeyDown(Keyboard.KEY_W))
        cam.move(cam.getMoveSpeed() * speedMultiplier, Camera.MOVE_FORWARD);

    if (Keyboard.isKeyDown(Keyboard.KEY_S))
        cam.move(cam.getMoveSpeed() * speedMultiplier, Camera.MOVE_BACKWARD);

    if (Keyboard.isKeyDown(Keyboard.KEY_A))
        cam.move(cam.getMoveSpeed() * speedMultiplier, Camera.MOVE_LEFT);

    if (Keyboard.isKeyDown(Keyboard.KEY_D))
        cam.move(cam.getMoveSpeed() * speedMultiplier, Camera.MOVE_RIGHT);

    cam.carryCamera(); //MOVES THE ACTUAL CAMERA TO THE HOLDER.
    speedMultiplier = 1;

}

public void update() {
    applyJBullet();
}

        //AND JBULLET PHYSICS ARE APPLIED HERE (SUSPICIOUS CODE!!!)
public void applyJBullet(){
Engine.getDynamicsWorld().stepSimulation(1/60.f, 10); //SIMULATES NEXT FRAME

    for (Object o : objects) { 
        if(o.getMass() >= 1){ //ALL THE OBJECTS WITH MASS ARE FOUND

    Transform trans = new Transform();   //CREATING A NEW TRANSFORM
    o.getBody().getMotionState().getWorldTransform(trans); //GET THE SIMULATED LOCATION

//It still doesn't work when I do: "trans.origin.x+=2" here. The same problem occurs.
    o.setPos(trans.origin); //AND SET IT AS THE OBJECTS POSITION
        }   
    }
}

Answer 1

我认为比仅仅使用盒子形状更好的原因是拥有一个运动体。要将相机机身变成“运动体”(最好是单向碰撞，由用户移动)，请调用以下命令:

body.setCollisionFlags(body.ge­tCollisionFlags() | CollisionFlags.KINEMATIC_OBJEC­T);
body.setActivationState(Collis­ionObject.DISABLE_DEACTIVATION­);