Material Binding
This sub-section is still under development, we'll add more advanced binding lookups in the near future!
Looking up material bindings is as simple as running materials, relationships = UsdShade.MaterialBindingAPI.ComputeBoundMaterials([<list of prims>].
This gives us the bound material as a UsdShade.Material object and the relationship that bound it.
That means if the binding came from a parent prim, we'll get the material:binding relationship from the parent.
from pxr import Sdf, Usd, UsdGeom, UsdShade
stage = Usd.Stage.CreateInMemory()
# Leaf prims
cube_prim = stage.DefinePrim(Sdf.Path("/root/RENDER/pointy/cube"), "Cube")
sphere_prim = stage.DefinePrim(Sdf.Path("/root/RENDER/round_grp/sphere"), "Sphere")
cylinder_prim = stage.DefinePrim(Sdf.Path("/root/RENDER/round_grp/cylinder"), "Cylinder")
round_grp_prim = sphere_prim.GetParent()
material_prim = stage.DefinePrim(Sdf.Path("/root/MATERIALS/example_material"), "Material")
# Parent prims
for prim in stage.Traverse():
if prim.GetName() not in ("cube", "sphere", "cylinder", "example_material"):
prim.SetTypeName("Xform")
# Bind materials via direct binding
material = UsdShade.Material(material_prim)
# Bind parent group
mat_bind_api = UsdShade.MaterialBindingAPI.Apply(round_grp_prim)
mat_bind_api.Bind(material)
# Bind leaf prim
mat_bind_api = UsdShade.MaterialBindingAPI.Apply(cube_prim)
mat_bind_api.Bind(material)
# Query material bindings
materials, relationships = UsdShade.MaterialBindingAPI.ComputeBoundMaterials([cube_prim, sphere_prim, cylinder_prim])
for material, relationship in zip(materials, relationships):
print(material.GetPath(), relationship.GetPath())
"""Returns
/root/MATERIALS/example_material /root/RENDER/pointy/cube.material:binding
/root/MATERIALS/example_material /root/RENDER/round_grp.material:binding
/root/MATERIALS/example_material /root/RENDER/round_grp.material:binding
"""