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Defining Rag Doll Limits 743
constraint spaces, the child cannot rotate more
than 5 degrees clockwise about the t wist axis.
Cone M in—The m inimum va lue, in degrees, used
to specify the limit cone. This value combines with
theConeMaxvaluetogenerateasymmetrical
cone. This cone is rotated about the plane normal
by an offset calculat ed by combining these limits.
The rotation of the child’s twist axis is then limited
tothevolumeofthisconewithrespecttothe
parent.
For example, if the Min=–10 and Max=20, the
range is 30 degrees. A 30-deg ree cone [–15,15] is
created about the twist axis and is then rotated
by the offset between the limits (–10+20 )*0.5=5.
This results in the effective limits being [–15,15]
rotated by 5 degrees, thus final limits of [–10, 20].
Co ne Max—The maximum value, in degrees, used
to specify the limit cone. This is combined with the
Cone Min value to generate a symmetrical cone.
This cone is rotated about the plane normal by an
offset ca lculated by combining these limits. The
rotation of the child’s twist axis is then limited to
being within this cone with respect to the parent.
Plane Min—Theanglebetweentheplaneanda
referencelineintherange[-90,0]. Thislineis
swept about the plane normal to create a cone. The
child’s twist axis is then restricted from entering
thiscone.Ifthisconeintersectstheconeproduced
by the cone limits, it further inhibits the motion of
the child with respect to the parent.
Plane Max—The angle between the plane and a
referencelineintherange[0,90].Thislineisswept
about the plane normal to create a cone. The
child’s twist axis is then restricted from entering
thiscone.Ifthisconeintersectstheconeproduced
by the cone limits, it further inhibits the motion of
the child with respect to the parent.
Breakable group
B r ea kab l e—When on, the constraint is breakable.
If its breakable limits are exceeded during
simulation it will cease to exert impulses on the
attached objects. You can find out more about
breakable constraints in Breakable Constrain ts
(page 2–735).
Display group
Show Twist—When on, Twist limits display as
part of the Par ent Space visualization. The
representat ion is a c ylinder section showing the
restricted motion of the attached object with
respect to rotation about the twist axis.
Show Cone—When on, the entire symmetrical
coneproducedbytheCone>MinandMaxlimits
displays as part of the Parent Space visualization.
Show Plane—When on, representations of the
plane and plane normal display as part of the
Parent Space visualization.
Show Plane Limits—When on, the cones formed by
the plane limits display as part of the Parent Space
visualization.
Show Volume—If true, a representation of
the allowed region of movement based on a
combination of the plane and cone values will
be calculated and displayed as part of the Parent
Space visualization.
Size—Allows you to change the size of the limit
visualiza tion in the viewport.
Reset Default Values—Resets the p arameters for
this constraint to their default values.
Defining Rag Doll Limits
The Rag Doll constraint (page 2–737) is useful for
simulating complex joints, like those found in
some human and animal joints (shoulders, hips),
that cannot b e properly simulated by simpler