= Node and parameter paths =

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Every node and parameter has a unique _pathname_ you can use to refer to
it.

The organization of data in Houdini is very similar to a UNIX file
system.

* The root path is `/`.

* The next level is the _list type_. This is one of `obj` (objects),
  `comp` (compositing operators), `out` (render output operators),
  `part` (particle operators), `ch` (channel operators), `shop` (shader
  operators), or `vex` (VEX builder operators).

* Next comes any subnet names.

* Next is the node name.

* You can also specify a parameter name inside the node.

As in a filesystem, you can use `.` (here) and `..` (up one level) to
refer to nodes and parameters by their position relative to the current
context. For example, in a sphere node at `/obj/geo1/sphere1`, you can
refer to the `radiusy` parameter on another sphere node at the same
level with `../sphere2/radiusy`.

== Examples ==

`/obj/geo1/sphere1/tx` :
    The Translate X parameter of `sphere1` inside `geo1`.
`/comp/comp1/color3/colorr` :
    The red color component of the `color3` color COP inside COP
    network `comp1`.