Microsoft KB Archive/180235

HOWTO: Use the Chain Behavior Effect

PSS ID Number: Q180235 Article last modified on 02-06-1998

IRIX:3.7; WINNT:3.7

IRIX winnt

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The information in this article applies to:

 Softimage 3D for IRIX, version 3.7 == Softimage 3D for Windows NT, version 3.7 == 

= SUMMARY =

This article offers steps for using the Chain Behavior effect.

The advantage of using this technique rather than explicitly keyframing the up vector, is that you do not have to define the chain behavior at a certain keyframe but, instead, at a position. When your character reaches this position, the up vector moves accordingly, which eliminates flipping.

= MORE INFORMATION =

Complete the following instructions on using the Chain Behavior effect:


 * 1) In the Front view, draw a 2-joint 2D skeleton with automatic up vector.
 * 2) Move the up vector in a position so that when you move the effector, the joint flips, not the up effector.
 * 3) Get a 1-unit cube and place it above the effector.
 * 4) Constrain the effector to the cube.
 * 5) From the Actor module, choose Skeleton -> Chain Behavior.
 * 6) Remove the name in the dialog box (you can add the name and save the effect once the chain behavior has been explicitly given).
 * 7) Click Load, and pick the objects, the object to track is the cube, and then for Up vector, pick the null.
 * 8) Move the cube around to see the joint flip when you pass the preferred axis.
 * 9) Select the effect icon (it is the 1-joint chain) and detach it (Effect -> Custom -> Detach Effect).

Define the Chain Behavior

 * 1) Select the cube and choose Savekey ->Add control key.
 * 2) Move the cube so that the joint flips.
 * 3) Select the NULL’s up vector and move it so that the joint is back in the desired orientation.
 * 4) Select the cube again, and choose Savekey -> Add control key.
 * 5) To re-attach the effect, select the icon, and choose Effect -> Custom -> Reattach.
 * 6) Now, when you move the cube, the up vector moves so that the joint does not flip.
 * 7) You can save the chain behavior and apply it to a different chain.

= REFERENCES =

If you have any questions concerning the information contained in this article, contact support@softimage.com by e-mail.

= Additional query words: si si3d si3dact =

Keywords : si si3d si3dact Version : IRIX:3.7; WINNT:3.7 Platform : IRIX winnt Issue type : kbhowto ============================================================================= Copyright Microsoft Corporation 1998.