transform.localPosition of a node instead of a part

[flart]

I have this function based on the one in the Konstruction mod:

private Vector3 GetOffset(WeldingData wData)
{
    //var nodeA = WeldingNodeUtilities.GetLinkingNode(wData.LinkedPartA, wData.part0);
    //var nodeB = WeldingNodeUtilities.GetLinkingNode(wData.LinkedPartB, wData.part0);

    //Vector3 offset = nodeA.position - nodeB.position;   // offset in wrong direction, depends an an angle of the craft? 
    //Vector3 offset2 = nodeA.nodeTransform.localPosition - nodeB.nodeTransform.localPosition;   // // nulref 

    // works for a stack of simple simmetrical parts (tanks)
    Vector3 offset3 = wData.LinkedPartA.transform.localPosition - wData.LinkedPartB.transform.localPosition;
    offset3.Normalize();
    offset3 *= WeldingNodeUtilities.GetPartThickness(wData.part0);
    return offset3;
}

// .....

partB.transform.position += offset;

Idea there pretty simple, we take vector (direction) of an future shift as difference of positions, normalize it, and then give it the desired length.

offset3 use linked parts for that difference, while mathematically it's enough (and make more sense) to use corresponding nodes of the part0 for that difference. Also this way it will not be dependent on models of linked parts. (I consider .transform.localPosition as some kind of center of a part).

I have tried to use nodes (offset, offset2), but it is failed. How to switch to using nodes?  

 

 

[zer0Kerbal]

@Lisias?

[flart]

the solution is 
 

Vector3 offset =
    nodeA.owner.transform.rotation * nodeA.position + nodeA.owner.transform.position -
    nodeB.owner.transform.rotation * nodeB.position + nodeB.owner.transform.position;

or simplified:

Vector3 offset = part.transform.rotation * (nodeA.position - nodeB.position);