2009

Add Path Adds a new spline path that influences the constrained object.
Delete path Removes a path from the target list. Once removing the path
target, it will no longer influence the constrained object
Weight Assigns and animates weight values for each target.
% Along Path Sets the percent that the object is positioned along the path.
This duplicates the Value spinner in the track Properties dialog for the Percent
track in Track View. If you want to set keys to place an object at a certain
percent along the path, turn on Auto Key, move to the frame where you want
the key set, and adjust the % Along Path spinner to move the object.
NOTE The % Along Path value is based on the parameterization of the spline
path’s U value. A NURBS curve might not have an evenly spaced U value, so a
value of 50 % Along Path might not translate visually to 50 per cent of the NURBS
curve’s length.
Follow Aligns the object to the trajectory as it follows the contour.
Bank Allows the object to bank (roll) as it negotiates the curves of the spline.
Bank Amount Adjusts the amount of the banking to one side or the other,
depending on whether the value is positive or negative.
Smoothness Controls how rapidly the roll angle changes as the object moves
through bends in the trajectory. Smaller values will make the object more
responsive to subtle changes in the curve, while larger values smooth out
jerking. The default value is a good value for general damping along the curve.
Values below 2 tend to make the action jerky, but values around 3 can be very
useful for simulating a certain degree of realistic instability.
Allow Upside Down Turn on to avoid the situation in which an object flips
when going around a vertically oriented path.
Constant Velocity Provides a constant velocity along the path. When off,
the velocity of the object along the path varies depending on the distance
between the vertices on the path.
Loop By default, when the constrained object reaches the end of a path it can
no longer move past the end point. The loop option changes this behavior
so that when the constrained object reaches the end of the path it loops back
to the starting point.
Relative Turn on to maintain the original position of the constrained object.
The object will follow the path with an offset distance based on its original
world space position.
3302 | Chapter 15 Animation