** Rendering options (toggle):
f - facets        l - lines          g - const. entities
c - obj. color    e - material       b - back color
A - axis          B - box            G - grid
C - capping       r(R) - hide (show) refs.
n - smooth/flat shading

** Controls options:
i - reset view    a - animate        I - interactive
h - online help   q - quit           X - close window

** View controls (ALT + key):
c - copy   d - duplicate p - paste  l - link   u - unlink
J - toggle flight        y - change axis

** Misc. features
L - load prefs    W - save prefs
H - hardcopy PPM
F - face nums     P - point nums     # - select entity
N - normals       O - oppos. normals ! - select plane
m - data          o - iso-lines      w - tensor/vector
v - streamlines   k - toggle elev.   K - elev. coeff.
j - toggle deco   p - palette        S - play animation
+/- scale object  z/Z scale view
F1,F2,F3 - clipping: On/Off, Edit, Freeze