Why the downstream nodes won't respect the change?
839 1 0- wanglifu
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- mtucker
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Houdini tracks and automatically updates changes to _node_ paths, including in LOPs. So if you haev a LOP Fetch node pointing to /stage/foo, and you rename that node to /stage/bar, the Fetch LOP will update and point to the new node path. But most paths in LOPs are actually _USD primitive paths_. These sometimes correspond to node names, but not in any reliable way.
So it is not possible for Houdini to update USD primitive paths down the chain when you change a node path (because there is no way to track any purposeful or coincidental corespondence between the two). If you write your USD primitive paths using expressions like `opfullpath` or `opinput`, you can get some amount of automatic tracking. The other approach encouraged by LOPs is to use the `lopmodifiedprims` expression to grab the paths of all primitives modified by a particular node.
So it is not possible for Houdini to update USD primitive paths down the chain when you change a node path (because there is no way to track any purposeful or coincidental corespondence between the two). If you write your USD primitive paths using expressions like `opfullpath` or `opinput`, you can get some amount of automatic tracking. The other approach encouraged by LOPs is to use the `lopmodifiedprims` expression to grab the paths of all primitives modified by a particular node.
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