9

Spline IK Solver Rollouts 479
The options on this rollout allow you to pick a new
spline for the spline IK chain, or pick new start and
end joints for the chain.
Spline IK Solver group
Spline IK S olver—Displaysthenameofthesolver.
The only available solver is Spline IK Solver.
Enabled—Turns control of the solver on and off.
Bone Joints group
Pick Star t Joint—Picks the st art joint for the Spline
IK Solver and displays the object name.
Pick End Joint—Picks t he end joint for t he Spline
IK Solver and displays the object name.
IK Solver Proper ties rollo ut
The options on this rollout set the star t and end
tw ist ang les for the spline IK chain. The twist
manipulators on each end of the chain show t he
degree of twist.
Twi st St art A ngl e—Sets the twist angle for the entire
chain, rotating all b ones in the chain.
Twi st En d Ang le—Sets the twist angle for the end
jointrelativetothestartjoint,creatingagradual
tw ist over the entire chain.
Pick Upnode—When Spline IK is assigned to a
bone chain, the I K system attempts to determine
the “up” direction for bones, which is the direction
in which the bones’ back fins should point. The
Spline IK Solver might interpret this direction
incorrectly, causing bones to flip to one side or
the other. Picking an upnode causes the “up”
direction to point along the pick ed object’s local
Z axis. By default, the upnode is set to the first
helper/knot on the spline , which usually causes the
“up” direction to b e interpreted correctly.
Use—Use the picked node to specify the “up”
direction for the root bone.
IK Display Option s rollout
The options on this rollout set the display of twist
manipulators and the IK chain object.
Twist Start group
Enabled—Turns on the display of the start twist
manipulator. Default=on.
Size—Sets the size of the start twist manipulator.
Default=1.0.
Lengt h—Sets the length of the start twist
manipulator. Default=75.0