Extracting transformations from parenting

[ofer]

Hi.

When I parent one object to another, is there any way I can restrict the parenting to just one axis or transform type, or any way to extract the transformation of an object which is parented to another object?

I have two problems I'm trying to solve:

1. I want to create a LookAt control to a mechanical arm. I created a null object, oriented it and assign another null object as the LookAt object of the first one. Now, I can't just parent the mechanical arm to the first null object, because it is built from two parts, each should rotate only in one axis.

I can solve it using expressions and a TransformAxis SOP, but maybe there is a better way. Maybe with CHOPs?

2. I have a curve which is parented to another object. I use this curve as a wire object, and since the object is animated, and the curve is parented to is, I want the curve to react using DOPs. The problem is how to make the parent object transformations affect the curve's transformation as a wire object. Maybe parenting does not fit here, and I should use an object merge or Fetch or something like that. I'm still working on this one.

Thanks.

[michael]

have a look at the blend object

[ofer]

Amazing. I love this app.

I now need to solve the second issue.

Thanks a lot.

[michael]

post a quick eg of the second question....not easy to see what you're after...

[ofer]

Hmm, the blend object won't work good, because I need to constrain along a different axis then X/Y/Z. Maybe I should have created the object aligned, and move it to position later.

Is there anyway to make the blend object use the parents coordinate system? Maybe I should use the 'three inputs method'.