Near-future astronomical survey experiments, such as LSST, possess system requirements of unprecedented
fidelity that span photometry, astrometry and shape transfer. Some of these requirements flow directly to the
array of science imaging sensors at the focal plane. Availability of high quality characterization data acquired
in the course of our sensor development program has given us an opportunity to develop and test a framework
for simulation and modeling that is based on a limited set of physical and geometric effects. In this paper we
describe those models, provide quantitative comparisons between data and modeled response, and extrapolate
the response model to predict imaging array response to astronomical exposure. The emergent picture departs
from the notion of a fixed, rectilinear grid that maps photo-conversions to the potential well of the channel.
In place of that, we have a situation where structures from device fabrication, local silicon bulk resistivity
variations and photo-converted carrier patterns still accumulating at the channel, together influence and distort
positions within the photosensitive volume that map to pixel boundaries. Strategies for efficient extraction of
modeling parameters from routinely acquired characterization data are described. Methods for high fidelity
illumination/image distribution parameter retrieval, in the presence of such distortions, are also discussed.