2009

■ A twist axis, which is the axis around which the child body can twist
relative to the parent body. You use this axis to specify twist limits and
the child body's permitted cone of movement.
■ A plane and plane normal centered on the attachment point; the plane
serves to define further limits that restrict the child body's movement
within the cone.
reactor provides special limit visualizations to help you choose appropriate
values for the Rag Doll.
For a detailed explanation of how to define those limits, see
Defining Rag Doll
Limits
on page 3959.
reactor simulates a Rag Doll constraint if it has the correct number of rigid
bodies attached and is included in a valid Constraint Solver on page 3945. When
not selected, invalid rag dolls are red in the viewport.
To find out how to create an example character quickly using the Rag Doll
constraint, see
Scripts on page 4103.
Procedures
To create a Rag Doll constraint:
■ Choose one of the above options, and then click in any viewport to add
the Rag Doll.
NOTE For a two-bodied Rag Doll, the icon’s initial position has no effect on
the Rag Doll's behavior. For a single-bodied Rag Doll, it defines the initial
position of the world attachment point. You can change this afterwards.
To attach objects to the Rag Doll:
1 Create the rag doll and the objects to connect using it.
2 In the rag doll’s Properties rollout, click the Child pick button. Now, in
one of the viewports, select the object to use as the child object. This
attaches the constraint to the selected body at the body’s pivot point.
The twist axis for the constraint in the child's space is aligned to the x-axis
of the child object and initially, the plane normal will be aligned to the
y-axis.
This constraint is more intuitive to use if the child and parent bodies are
attached correctly. For example, if connecting an upper arm to a shoulder,
the shoulder should be the parent and the upper arm the child.
3950 | Chapter 16 reactor