Environment map based lighting for reflectance transformation images

Environment map based lighting has proven to be an effective technique in simulations and real time rendering for adding realism and conveying complex illumination to the viewer. We present a novel algorithm for using environment maps to light and render polynomial texture maps. The technique is demonstrated with reflectance transformation images stored using both polynomial texture maps and hemispherical harmonics. The limitations of employing hemispherical harmonics in this context are discussed.