SpatialTransformer.setObject question

What does parentIndex refer to?

The java docs are a little bit laconic.

SpatialTransformer.setObject(Spatial objChange, int index, int parentIndex)

Sets an object to animate.

I understand that one SpatialTransformer can control n objects

st = new SpatialTransfomer(2);

st.setObject(obj1, 0, …

st.setObject(obj2, 1, …

but there is no information about the third parameter, the parentIndex

anyone know what that does?

as a guestimate its for a parent spatialtransformer, allows you to have a tree structure where a child can be attached to a parent

The parent of a bicycle wheel are the bike it self ( or the steering mechanism ). The bike presumably tells the child wheel when to turn

hmm… kinda makes sense… looking through the source of some of the test apps… some of them set the parentIndex to -1