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Camera，这样它就可以掉落并发生碰撞。

问题是cameraHolder应该在按下特定的 WASD 键时移动，但它只移动一个单位并且不再移动。释放按钮后，它会将一个单位移动到相反的方向，以便您处于同一位置。在cameraHolder移动后，相机的 XYZ 设置为cameraHolder的 XYZ 坐标。

然而，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正常移动。所以问题应该是jBullet更新。 我将在代码中显示它。

问题：为什么cameraHolder只移动1个单位，然后在按下特定的 WASD 按钮时返回？

以下是Camera.java类中移动的代码：

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);
}

如何获取输入并更新物理（可疑代码在本部分）：

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。要将相机机身转变为“运动机身”（最好由用户移动单向碰撞），请拨打以下电话：

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

jBullet相机“持有人”不动

1 个答案: