Numerous tests were carried out on the two-dimensional facial model which was developed early in the project. One of these test programs, mouthtest.ps tested the two degrees of freedom (the smile-frown and closed-open dimensions) of the mouth in the facial model, by drawing a two-dimensional table of possible mouth shapes (see fig. 4.1).
Figure 5: ``Mouth space'', as rendered in the two-dimensional model.
Another program (exprspace.ps) rendered faces with the minimum, medium and maximum values for each of the facial parameters in the model at the time.