Method dolly

tutorials/common/tutorial/camera.h:116–121

    }

    void dolly (float ds)
    {
      float dollySpeed = 0.01f;
      float k = powf((1.0f-dollySpeed), ds);
      from += length(to-from) * (1-k) * normalize(to-from);
    }

  public:
    Vec3fa from;   //!< position of camera