Tree suggestions

I am still trying to port this tree generator my girlfriend made in java 3d.

it is quite simple and good.

as my first steps i have to look out that my navigations are correct.

So the tree itself is made out of Cylinders which i modified like i posted here

now my tree itself looks quite good i think.

but if i want to rotate it i am missing the origin of the cylinder and cant imagine how i can make these cylinders get one

i even know that this rotation is quite a bit too much but i only want to fit the lower side of one upper cylinder to the upper side of some lower Cylinder.