9

Parameter/Parametric 989
Par ameter /Par ametr ic
A tube is one example of a parametric object. Varying its
parameters c reates varying geom etry.
A parameter is a setting or value that you can
change. Many objects in 3ds Max have parameters
that you can change to a lter the size or shape of
the object. This ty pe of object can be described
as parametric.
Unlike physical bui lding blocks, which have a fixed
shape and size, the geometric primitives (box ,
sphere,torus,andsoon)areparametric;youcan
change their dimensions, segm ent sett i ngs, and
other features after you create them. Parametric
objects respond to changes in their parameters by
dynamically updating their properties.
Changing a parameter can dramatically alter
the st ructure and appearance of an object. For
example, you can turn a c ylinder into a prism
by reducing the number of sides and turning the
Smooth option off. Alternately, you can tur n a
cone into a four-sided pyramid using the same
technique.
Objects that you merge from other scenes or from
Autodesk VIZ allow you to access parametric
values. Objects in drawings that you link from
Autodesk Architectural Desktop should be edited
in Architectural Desktop, then relinked to 3ds Max
with the File Link Manager (page 3–422).
You can animate almost all creation parameters
for geometric primitives, and interactively change
their s ettings during a nimation playback.
Pa re nt Part icle
A parent particle is an existing particle from which
theparticlesystemgeneratesspawn particles
(page 3–1014).YoucanusetheSpawn test (page
2–230) to create spawn particles arbitrarily, or
the Collision Spawn test (page 2–215) to create
spawn particles as the result of physical interaction
between a p arent particle and a deflector.
Pa rti cle D i a gr a m
The particle diagram is the graphical depiction of
the particle system (page 3–990) in Particle View
(page 2–125).Itusesevents (page 3–935) and wires
(page 3–1033) to represent the system’s elements