Of course the ToonFace scheme provides nowhere near an exact match to the action of a human face (for
which even FACS is a simplification), but that is a problem all computer graphics schemes to date have in
common, to various degrees. Where the ToonFace scheme falls especially short is in facial expression involving the
physics of skin contraction and excessive exertion of muscle force, and in the combinatorial explosion possible with
combinations of the numerous action units included in FACS. With patience, a skilled ToonFace designer could
possibly approximate FACS better than indicated here, but that would be going against its design philosophy, which
is simply to get a handful of usable facial expressions relevant to multimodal dialogue, while allowing for a playful
design that doesnÕt get the userÕs expactations up.