We are used to looking at the output of a computer graphics
program on a monitor or on a screen. But, how can we see
the "special effects" directly in our environment ? For example,
how can we make a clay vase sitting on
a table look like it is made up of gold, with fine details ?
The appearance of an object is a function of illumination,
surface reflectance and viewer location. Hence, we can
rearrange the factors along the optical path and reproduce
the equivalent desired appearance.

We have recently introduced a new paradigm and
related techniques to graphically animate physical objects
with projectors. Because the approach is to effectively
"lift" the visual properties of the object into the
projector, we call the projectors shader lamps.
We address the central issue of complete illumination
of non-trivial physical objects using multiple projectors
and present a set of new techniques that
make the process of illumination practical.
We show some results and describe the new challenges in
graphics, geometry, vision and user interfaces.