The Load USD File node
When to use it
The USD counterpart to Load Alembic File. It streams a stage's frames in as something downstream asks for them, so scene length costs you nothing up front.
What it adds over the Alembic loader is Prim Filter Path and the purpose switches. A production stage carries far more than the one character you want, in several detail levels at once, and those settings are how you take the branch you need and leave the rest on disk.
There is no Load button. Pick a file and it reads, and it reads again the moment you change any setting below.
The stage's own up-axis and metersPerUnit are both ignored. Rotation is the only thing standing a Y-up scene upright, and a scene authored in metres arrives a hundred times too small until you scale it here.
Pins
| Pin | Type | Description |
|---|---|---|
StreamingCache |
Streaming Geometry Cache | The animated cache read from the USD stage, one frame at a time. |
Settings
| Setting | Type | Description |
|---|---|---|
Source File |
File path | The USD file to read. Pick one and the load runs straight away, and it runs again every time you change a setting below. |
Preset |
Choice | Which package wrote the file. Maya and 3ds Max fill in the Scale and Rotation those apps need. Touch either of those by hand and this flips to Custom. |
Scale |
Vector | Scale applied to every vertex as the stage is read. The default (1, -1, 1) only flips handedness, it does not resize anything. The stage's own metersPerUnit is ignored, so a scene authored in metres arrives a hundred times too small until you scale it here. |
Rotation |
Vector | Rotation in degrees applied to every vertex as the stage is read. The stage's own up-axis is ignored, so this is the only thing standing a Y-up scene upright. |
Flip U |
True/False | Mirrors the U coordinate. Turn it on if textures arrive reversed left to right. |
Flip V |
True/False | Mirrors the V coordinate. On by default. Switch it off and textures land upside down. |
Prim Filter Path |
Text | Read only one branch of the stage, by prim path (something like /Root/Characters/Hero). Leave it empty for the whole stage. On a big scene this is the difference between opening in a second and waiting on the whole thing. |
Include Default Purpose |
True/False | Include geometry that carries no purpose tag. This is where most hand-authored meshes live, so leaving it off usually gets you nothing. |
Include Render Purpose |
True/False | Include geometry tagged as render. That is the high-detail version meant for final frames. |
Include Proxy Purpose |
True/False | Include geometry tagged as proxy: the cheap stand-in a scene uses for fast playback. Turning this on alongside render usually gets you two copies of the same character sitting inside each other. |
Include Guide Purpose |
True/False | Include geometry tagged as guide: rig visualisers, motion paths and other things nobody wants in a sculpt. |
Available in Mesh Morpher Graph and Mesh Morpher Studio.