Set the Default Prim on a Stage
It’s best practice to set the defaultPrim
metadata on a Stage if the Stage’s root layer may be used as a Reference or Payload. Otherwise, consumers of your Stage are forced to provide a target prim when they create a Reference or Payload arc. Even though the Usd.Stage.SetDefaultPrim()
accepts any Usd.Prim
, the default prim must be a top-level prim on the Stage.
from pxr import Usd
def set_default_prim(stage: Usd.Stage, prim: Usd.Prim):
stage.SetDefaultPrim(prim)
#############
# Full Usage
#############
from pxr import UsdGeom, Sdf
# Create new USD stage for this sample
stage: Usd.Stage = Usd.Stage.CreateInMemory()
# Create an xform which should be set as the default prim
default_prim: Usd.Prim = UsdGeom.Xform.Define(stage, Sdf.Path("/World")).GetPrim()
# Make the xform the default prim
set_default_prim(stage, default_prim)
usda = stage.GetRootLayer().ExportToString()
print(usda)
# Check that the expected default prim was set
assert stage.GetDefaultPrim() == default_prim
This is an example USDA result from setting the defaultPrim
metadata in an empty layer.
#usda 1.0
(
defaultPrim = "World"
)
def Xform "World"
{
}