©2002 RigidSoftware

Notes:

Offsets

Interpolation of offset values causes a double interpolation effect. This is because the percentage of application of the offsets are also interpolated.  If both have  linear interpolation then the percentage's linear interpolation combined with the offsets' linear interpolation creates a nonlinear application of offsets. This nonlinear application of offsets will not counteract the linear application of the constraint (except at 0% and 100%)

This effect may often go unnoticed.  However, it often leads to compensation mode not working correctly.  The larger the offset values, the more you will notice the effect.  If your object is not supposed to move, you will indeed notice motion.

Look at this quicktime movie (sorensen compression) trans2.mov.  Notice that LeftObject is  properly moving toward its constrained position, as is MiddleObject.  But now regard RightObject. It starts where it should finish. Yet, the animation forces it to move away from its target (around 50% pose slider) only to move back as the pose slider nears 100%.

Translate To Constraint

The “Translate  To” constraint not only translates object 1 to object 2, but also causes object1’s position to be affected by the orientation of object 2. This allows one object’s surface patches to be constrained to a second object’s surface patches by using offsets.  When the first object moves, the second object will follow. Imagine a thick hand, with the bone deep inside. When the hand rotates, the object constrained to its surface should rotate as well, around the internal bone and stay in place on the surface. This constraint is probably better named “Attach To ”.

Look at this quicktime movie (sorensen compression) trans1.mov. All top objects are constrained to the bottom objects.  However, the objects are offset from their natural constrained position through the use of compensate mode. Notice how the top objects dance around the bottom object. This is indeed correct behavior for this constraint, as it preserves the displacement and relative orientation between the two objects.

Modified:  Saturday, February 22, 2003