  We present a new numerical algorithm for the calculation of pulse profiles
from spinning neutron stars in the Hartle-Thorne approximation. Our approach
allows us to formally take into account the effects of Doppler shifts and
aberration, of frame dragging, as well as of the oblateness of the stellar
surface and of its quadrupole moment. We confirm an earlier result that
neglecting the oblateness of the neutron-star surface leads to ~5-30% errors in
the calculated profiles and further show that neglecting the quadrupole moment
of its spacetime leads to ~1-5% errors at a spin frequency of 600 Hz. We
discuss the implications of our results for the measurements of neutron-star
masses and radii with upcoming X-ray missions, such as NASA's NICER and ESA's
LOFT.
