Create a Variant Set
Note
If this is your first time authoring a variant set, we recommend that you follow Authoring Variants USD tutorial first.
A Variant Set is a composition arc that serves as a sort of “switchable Reference” allowing you to provide alternate property opinions or entire prim hierarchies. In this snippet, you’ll find how to create a Variant Set, add variants to the new Variant Set and author opinions for each variant.
from pxr import Usd
def create_variant_set(prim: Usd.Prim, variant_set_name: str, variants: list) -> Usd.VariantSet:
variant_set = prim.GetVariantSets().AddVariantSet(variant_set_name)
for variant in variants:
variant_set.AddVariant(variant)
return variant_set
#############
# Full Usage
#############
from pxr import Sdf, UsdGeom
# Create an in-memory Stage with /World Xform prim as the default prim
stage: Usd.Stage = Usd.Stage.CreateInMemory()
default_prim: Usd.Prim = UsdGeom.Xform.Define(stage, Sdf.Path("/World")).GetPrim()
stage.SetDefaultPrim(default_prim)
# Create the variant set and add your variants to it.
variants = ["red", "blue", "green"]
shading_varset: Usd.VariantSet = create_variant_set(default_prim, "shading", variants)
usda = stage.GetRootLayer().ExportToString()
print(usda)
assert default_prim.GetVariantSets().HasVariantSet("shading")
This is an example USDA result from creating a Variant Set and adding Variants to the Set.
#usda 1.0
(
defaultPrim = "World"
)
def Xform "World" (
prepend variantSets = "shading"
)
{
variantSet "shading" = {
"blue" {
}
"green" {
}
"red" {
}
}
}