  Limb darkening laws are convenient parameterizations of the stellar intensity
center-to-limb variation, and their use is ubiquitous in eclipse and transit
modeling. But they are not "laws" in any sense -- they are simple
approximations of the real intensity variations, and their limitations are
becoming more and more apparent as stellar atmosphere models improve and higher
precision data become available. When fitting eclipses and transit light
curves, one would ideally like to use model intensities that are based on
fundamental stellar parameters such as the mass, radius, and effective
temperature of the star, rather than a limb darkening law representation and
its coefficients. This is especially true when attempting to detect
higher-order effects such as planetary oblateness, rings, satellites, or
atmospheres. However, using model intensities requires numerically integrating
many small-area "tiles" on the model stellar surface(s) and this has
traditionally been too computationally expensive for general use. Here we
present a fast technique to compute light curves and the Rossiter-McLaughlin
effect that uses tabulated stellar models intensities. This is a step in the
development of tools that obviate the need for limb darkening laws.
