9

Dynamics Objects 395
Problem #3: Poor alignment of original primitive
meshes causes undesirable results.
Solut ion: Rotate or move original primitives into
position to maximize mesh quality.
The following illustration shows the result of
subtracting three spheres of the same size from a
box. The left-hand sphere is a ligned properly so
that there are good quads along both boundaries.
This should produce a good result when smoothed.
Themiddlespherewasliftedsothatthereisa
strip of very thin quads near the boundary. This
produces very little smoothing along that edge, as
you can see in the rendered image. The right-hand
sphere was rotated, producing poor alignment
and many t r iangles on the sphere as well as small
quads on the plane of the box. You can see the
undesirable results in the rendered image.
Quads produce d by three spheres with dif ferent rotations and
translations
Rendered image of smoothed three-sphere example
Cr eati ng D yna mics Obj ect s
Create panel > Geometry > Dynamics Objects
Create menu > D ynamics
Dynamics objects are similar to other mesh
objects, except that they can be made to react to
the motion of objects to which they are bound, or
they can provide dynamic forces when included in
a dynamics simulation (page 2–686).
Thefollowingtopicsdescribethetypesof
dynamics objects and how to create and use them:
Spring Dynamics Ob ject (page 1–400)
Damper Dynamics Ob ject (page 1–396)