View Full Version : transform propagation between child and parent

02 February 2007, 05:18 PM
hy having a bit of a hard time solving a problem.
what im doing, is trying to redirect a character's animation, by parenting the rig
to different nulls, and then rotating them at the time where the direction change needs
to take place. the technique works like charm under maya, but, replicating the same
idea under xsi gives me headaches.
problem is, if in xsi (as in maya for that matter), u parent an animated null under another null that has some translation on it...the moment u do that, the current child inherits the parents transforms and moves in space the same amount that the parent has moved (obviously). In maya, u just freeze the transforms for the parent null, and thats it, no more problems, but in xsi, no matter how many times i use the freeze transformation option, it just does not seem to solve the problem.
i know i must be doing something wrong, thats why id like to know what im doing wrong...
any ideas?

EDIT: i actually found out why this is happening, but its just getting weirder:
from the manual: "In softimage 3d, u can use Freeze Transformation command on nulls and other non-geometric objects. However in thesecases the transformations are actually reset instead of frozen. In xsi , use the reset command on the transform menu for the same behaviour".
ok, so i got it, but then why does xsi do the same thing on nulls if its described as a softimage 3d thing...and i havent setup any softimage 3d mode or anything.
Stranger thing is that the reset transform and the freeze transform command does exactly the same thing on nulls. why is this happening?

02 February 2007, 09:35 PM
set neutral pose maybe?

02 February 2007, 09:39 PM
If I'm not mistaken, you need to click on Constraint Compensation before parenting the null.

02 February 2007, 12:05 AM
hey guys
thanx for the quick replies
though...setting neutral pose on nulls solves the "freeze transformation" problem
it still propagates the actual transform to the it doesn't do any good.
as for using cns and child comp , nothing happens, and the same problem occurs even
if i parent with the buttons active
i've actually solved the problem by using simple cube primitives instead of nulls
for parenting (as freeze transform works on them)..but i still feel this is kinda weird
coming from maya, where this was very straightforward.
thanx for your help anyway.. :)

02 February 2007, 03:44 AM
Null is just a point in space, hence when you freeze its transformation it just goes back to center of the world.
If you do have ChildComp on then the transformation of the parent will not propogate to the child.

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02 February 2007, 03:44 AM
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