effects
=======

Effect
++++++


Base class for representing the effects (artifacts) in an optical system.

The ``Effect`` class is conceived to independently apply the changes that
an optical component (or series thereof) has on an incoming 3D description
of an on-sky object. In other words, **an Effect object should receive a
derivative of a ``Source`` object, alter it somehow, and return it**.

The interface for the Effect base-class has been kept very general so that
it can easily be sub-classed as data for new effects becomes available.
Essentially, a sub-classed Effects object must only contain the following
attributes:

* ``self.meta`` - a dictionary to contain metadata.
* ``self.apply_to(obj, **kwargs)`` - a method which accepts a
  Source-derivative and returns an instance of the same class as ``obj``
* ``self.fov_grid(which="", **kwargs)``


Parameters
----------
See :class:`DataContainer` for input parameters