  We present a new Monte-Carlo radiative transfer code, which we have used to
model the cyclotron line features in the environment of a variable magnetic
field and plasma density. The code accepts an input continuum and performs only
the line transfer by including the three cyclotron resonant processes
(cyclotron absorption, cyclotron emission, cyclotron scattering). Subsequently,
the effects of gravitational red-shift and light bending on the emergent
spectra are computed. We have applied our code to predict the observable
spectra from three different emission geometries; 1) an optically thin slab
near the stellar surface, 2) an accretion mound formed by the accumulation of
the accreted matter, 3) an accretion column representing the zone of a settling
flow onto the star. Our results show that the locally emergent spectra from the
emission volume are significantly anisotropic. However, in the presence of
strong light bending the anisotropy reduces considerably. This averaging also
drastically reduces the strength of harmonics higher than second in the
observable cyclotron spectra. We find that uniform field slabs produce line
features that are too narrow, and mounds with large magnetic distortions
produce features that are too wide compared to the average widths of the
spectral features observed from various sources. The column with a gently
varying (dipole) field produces widths in the intermediate range, similar to
those observed.
