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3 In the Dynamics panel > Objects in Simulation group, click the Select
Objects In Sim button.
All objects included in the simulation are selected.
4 Open a Track View window, and then set its filter to show Animated
Tracks Only and Selected Objects Only.
5 Right-click the top object in the Hierarchy list (Objects), and choose
Expand All.
Track View now shows all tracks in the simulation that have keys.
6 Go to Edit Time display mode and select all of the tracks containing keys
(or right-click over the hierarchy, and choose Select All).
7 Double-click any key to select all keys in all tracks.
8 Click the Reduce Keys button, set the Threshold to what you want, and
then click OK.
All selected keys are reduced.
9 Save the reduced version of the scene either under a new name, or by
replacing the original file.
To use linked hierarchies in a simulation:
When linked hierarchies are included in your simulation, you must set locks
for the children in the simulation to confine the dynamics results to specific
axes. Do this on the Hierarchy panel > Link Info >
Locks rollout on page 3501.
The Locks rollout contains three rows of check boxes affecting the XYZ axes
of the three possible transforms: Move, Rotate, and Scale. The Scale transforms
are ignored, and only the Move and Rotate locks are used. When a check box
is turned on, that axis of the specific transform is locked.
When you manipulate a forward-kinematics hierarchy directly using the Move
or Rotate tools, you might not bother with the Link Info locks, because you
can specify axis constraints using the X, Y , Z, and XY buttons in the toolbar.
However, when you use that same hierarchy in a dynamics simulation, where
there are several forces at work (gravity, wind, collisions), the only thing that
maintains the linkage between the objects is the locks you set in the Link Info
> Locks rollout. As a result, no matter what combination of Move and Rotate
locks you use, you'll always want at least one Move lock in place, or your
objects won’t really be linked.
The following lists all of the combinations of Move and Rotate locks that make
sense within a dynamics simulation, and the effect on the link of such
3858 | Chapter 15 Animation