  In this brief communication a new method is outlined for modelling
magnification patterns on an observer's plane using a first order approximation
to the null geodesic path equations for a point mass lens. For each ray emitted
from a source, an explicit calculation is made for the change in position on
the observer's plane due to each lens mass. By counting the number of points in
each small area of the observer's plane, the magnification at that point can be
determined. This allows for a very simple and transparent algorithm. A short
Matlab code sample for creating simple magnification maps due to multiple point
lenses is included in an appendix.
