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826 Chapter 13: reactor
theprimitivesinsidethegroup,you’llneedtoopen
it and selected the individual primitives inside it.
R igi d bodi es don’t bounce enough.
Increase the Elasticity property (page 2–717) of
the object. Try also increasing the E lasticity of
the other object involved in the collisions, as the
elasticity of a collisions is a function of the elasticity
property (page 2–717) of the two objects involved.
Objects stop movin g unex pectedly in
the middle of a simulation.
This can be caused by objects being deactivated.
There are two ways objects can be deactivated:
through t he world (page 2–808) deactivation or,
if the object belongs to a constrained system,
through the Constraint Solver (page 2–736)
deactivation parameters
In b oth cases, try modifying the deactivation
parameters for a less-aggressive deactivation, or
disable deactivation in general.
An object doesn’ t move during the
simulation.
Make sure that you’ve added the object to a
RBCollection (page 2–723) andthatithasamass
(page 2–717) other than 0.0 (objects with mass 0.0
are fixed). If you are using Fracture (page 2–770),
makesurenoneofthepiecesisfixed(hasmass
0.0).
A keyf r amed obj ect doesn’t move dur i ng
the simulation.
Make sure that you enabled the unyielding (page
2–717) property for that rigid body.
My old s cr i pts don’t work .
reactor exposes parameters and functionality
to MAXScript in a much more consistent and
complete way than previously. For the update,
some reactor MAXScript interfaces had to
be renamed, but all functionality exposed in
previous versions is still available, and a lot more
functionality has been exposed. While this means
that some reactor-specific scripts need to be
updated, it also means that a great deal more
flexibility and power is now achievable using
MAXScript with reactor. For more information,
see the MAXScript Reference, available from the
Help menu.
I can’t I disable collisions between two
bodies.
If your objects don’t appear in the Define Collisions
dialog (page 2–811),makesureyou’veadded
the two bodies to a collection; only objects in
collectionsareshowninthatdialog.
R igid bodi es don’t s ink /don’t f loa t i n the
wa te r.
Objects sink or float depending on their density
and the density of the water. You define water
density explicitly in the Water space warp (page
2–801).Thedensityofarigidbodyisdefinedas
its mass divided by its volume.
• Check that your objects have real-world sizes
(or adjust the world scale (page 2–808))and
masses (page 2–717).
If your bodies still don’t sink enough for your
liking, try the following:
• Increasethemassofthebodies.
• Decrease the density of the water.
• Decrease the viscosity of the water, t his can
slow down the sinking.
Followtheoppositestepsifyou’retryingtomake
your objects float more.
Water d oesn’ t r ippl e enough
You can either increase the Max Ripple value in the
Water space warp (page 2–801), or you can scale
the effect of the space warp on a particular object