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188 Chapter 5: Creating Geometry
Inter face
Fam ily group
Usethisgrouptoselectthetypeofpolyhedronto
create.
Tetra—Creates a tetrahedron.
Cube/Octa— Creates a cubic or octahedral
polyhedron (depending on parameter settings).
Dodec/Icos—Creates a dodecahedron or
icosahedron (depending on parameter settings).
Star1/Star2—Creates two different star-like
polyhedra.
Tip: You can animate between Hedra types.
TurnontheAutoKeybutton,gotoanyframe,
and change t he Fami ly check box. There is no
interpolation between types; the model simply
jumps from a star to a cube or tetrahedron, and
so on.
Family para meters group
P, Q —Interrelated parameters that provide a
two-way tr a nslation between the vertices and
facets of a polyhedron. They share the following:
• Rangeofpossiblevaluesis0.0through1.0.
• The combined total of the P and Q values can
be equal to or less than 1.0.
• Extremes occur if either P or Q is set to 1 .0; the
other is automatically set to 0.0.
• Midpoint occurs when both P and Q are 0.
In the simplest terms, P and Q change the
geometry back and forth between vertices and
facets. At the extreme settings for P and Q,
one parameter represents al l vert ices, the other
represents all facets. Intermediate settings are
transition points, with the midpoint an even
balancebetweenthetwoparameters.
Axis Scaling group
Polyhedra can have as many as three k inds of
polygonal facets, such as triangle, square, or
pentagon. These facets can be regular or irregular.
If a polyhedron has only one or two types of facet,
only one or two of the axis scaling parameters are
active. Inactive parameters have no effect.
P, Q, R —Controls the axis of reflection for one of
the facets of a polyhe dron. In practice, these fields