Code:

static glm::vec4 Rotation;auto q = worldTrans.getRotation();btVector3 v = q.getAxis();Rotation.x = v.x();Rotation.y = v.y();Rotation.z = v.z();Rotation.w = q.getAngle();spaceship->MotionStateSetRotation(Rotation);

Code:

static btScalar yaw;static btScalar pitch;static btScalar roll;worldTrans.getBasis().getEulerZYX(roll, pitch, yaw, 1);yaw = glm::degrees(yaw);pitch = glm::degrees(pitch);roll = glm::degrees(roll);spaceship->MotionStateSetYawPitchRoll(yaw, pitch, roll);

Code:

maxSubsteps = static_cast<int>(delta / (1.f / 60.0f) + 0.5f) + 1;

Code:

void SpaceShipMotionState::getWorldTransform(btTransform& worldTrans) const{float yaw, pitch, roll;auto p = spaceship->MotionStateGetPos();auto r = spaceship->MotionStateGetRotation();spaceship->MotionStateGetYawPitchRoll(yaw, pitch, roll);auto pos = btVector3(p.x, p.y, p.z);worldTrans.setOrigin(pos);btQuaternion q;q.setRotation(btVector3(r.x, r.y, r.z), r.w);worldTrans.setRotation(q);//q.setEulerZYX(roll, pitch, yaw);//worldTrans.setRotation(q);}void SpaceShipMotionState::setWorldTransform(const btTransform& worldTrans){auto p = worldTrans.getOrigin();glm::vec3 pos = { p.x(), p.y(), p.z() };spaceship->MotionStateSetPosition(pos);static glm::vec4 Rotation;auto q = worldTrans.getRotation();btVector3 v = q.getAxis();Rotation.x = v.x();Rotation.y = v.y();Rotation.z = v.z();Rotation.w = q.getAngle();spaceship->MotionStateSetRotation(Rotation);static btScalar yaw;static btScalar pitch;static btScalar roll;worldTrans.getBasis().getEulerZYX(roll, pitch, yaw, 1);yaw = glm::degrees(yaw);pitch = glm::degrees(pitch);roll = glm::degrees(roll);spaceship->MotionStateSetYawPitchRoll(yaw, pitch, roll);}

Code:

class MyMotionState : public btMotionState{    btRigidBody* m_body;    GameObject* m_gameObject;public:    MyMotionState(btRigidBody* body, GameObject* gameObject)        :   m_body(body), m_gameObject(gameObject)    {}    // getWorldTransform() relays transform from external logic to Bullet.    // It is called by Bullet in two places:    // (1) Once when the Body is created and added to the world.    // (2) Once per substep iff the Body is Kinematic and active.    //    void getWorldTransform(btTransform& worldTrans) const {        // Note: worldTrans is passed by reference        // It is our duty here to copy into it the correct transform as known        // to external logic and Bullet will harvest·        //·        m_gameObject->getWorldTransform(worldTrans);    }    // setWorldTransform() relays Body transform from the Bullet simulation to the GameObject    // and is called once per substep iff the Body is Dynamic and active.    //    void setWorldTransform(const btTransform& worldTrans) {        // It is our duty here to apply worldTrans to GameObject.        // Note: worldTrans is NOT necessarily the Body's transform as known to Bullet.        // It is an extrapolated transform based on the Body's state at the        // end of the last substep... extrapolated forward into the future (e.g. the remainder        // not yet stepped) according the current Body velocities.        //        m_gameObject->setWorldTransform(worldTrans);    }};

Code:

btTransform trans;(*body)->getMotionState()->getWorldTransform(trans);pos = trans.getOrigin();retPos = glm::vec3(pos.getX(), pos.getY(), pos.getZ());

Code:

// use mouse position to compute a delta-rotation in spaceship local-framebtQuaternion deltaLocalRotation(yaw, pitch, roll);// get old ship rotationbtTransform transform = body->getWorldTransform();btQuaternion oldBodyRotation = transform.getRotation();btQuaternion newBodyRotation = oldBodyRotation * deltaLocalRotation;transform.setRotation(newBodyRotation);body->setWorldTransform(transform);

Code:

maxSubsteps = static_cast<int>(fabs(delta / (1.f / 60.0f) + 0.5f)) + 1;

Code:

   ·///if maxSubSteps > 0, it will interpolate motion between fixedTimeStep's   ·virtual int stepSimulation(btScalar timeStep, int maxSubSteps = 1, btScalar fixedTimeStep = btScalar(1.) / btScalar(60.));