Layer Break USD

The name sounds dramatic. It isn't. Layer Break USD is a "flatten the current state" button: it takes everything your stage currently composes - references, sublayers, local edits, all of it - and bakes it down into one plain layer, then wraps that in a fresh stage. What you get out is a stage that looks identical but has none of the original composition structure left. That's the point.

You reach for it when composition has become a problem instead of a feature. Maybe your reference arcs are fighting your local edits, or a sublayer you added earlier is overriding things you didn't expect and you've spent an hour tracing which layer is winning. Or you're about to hand a stage to someone and you want them to see exactly what you see, not a tangle of file dependencies they don't have. One Layer Break and the fight is over - there's no longer any "which layer wins" to debug, because there's only one layer.

How it works

The mechanism is honest and slightly odd, so here's the actual sequence: the node takes your stage's root layer, exports it to a temp .usda file in ComfyUI's temp directory, then creates a brand-new in-memory stage and attaches that temp file as its single sublayer. All those composition arcs still exist inside the exported file, but they've been resolved into concrete opinions - the file is what the stage already decided, not the recipe that made it.

One input: USD (your stage). One output: USD (the baked stage). That's it. There's nothing to configure, which is refreshing.

Like Create USD Stage, it sets IS_CHANGED to NaN so it always re-runs and picks up the latest upstream state.

Install & what to expect

Standard pack install: ComfyUI Manager → search "ComfyUI-OpenUSD", or

cd ComfyUI/custom_nodes
git clone https://github.com/cjhosken/ComfyUI-OpenUSD

then restart. Deps: usd-core==26.5, numpy==2.5.0, trimesh.

A few honest caveats. First, the temp file lives in ComfyUI's temp folder and lingers there - harmless, but if you're weird about disk hygiene, know that repeated runs accumulate a few .usda files. Second, this is the pack's closest thing to a "destructive" node: it's one-way. Once you've flattened, the reference and sublayer structure is gone, so put it at the end of a branch you're done editing, not in the middle. And third, note that this node bakes composition but it does not convert your meshes or materials into something different - it's purely about collapsing the layer stack.