Add a SubLayer

A SubLayer is a composition arc used to build LayerStacks. In a LayerStack, the Layer that includes SubLayers has the strongest opinion. From there, the SubLayers are ordered from strongest to weakest starting from top to bottom (or first to last) in the subLayers list. This snippet shows how to create a new Layer and add it as a SubLayer.

USD Python

from pxr import Sdf


def add_sub_layer(sub_layer_path: str, root_layer) -> Sdf.Layer:
    sub_layer: Sdf.Layer = Sdf.Layer.CreateNew(sub_layer_path)
    # You can use standard python list.insert to add the subLayer to any position in the list
    root_layer.subLayerPaths.append(sub_layer.identifier)
    return sub_layer

#############
# Full Usage
#############

from pxr import Usd

# Get the root layer
stage: Usd.Stage = Usd.Stage.CreateInMemory()
root_layer: Sdf.Layer = stage.GetRootLayer()

# Add the sub layer to the root layer
sub_layer = add_sub_layer(r"C:/path/to/sublayer.usd", root_layer)

usda = stage.GetRootLayer().ExportToString()
print(usda)

# Check to see if the sublayer is loaded 
loaded_layers = root_layer.GetLoadedLayers()
assert sub_layer in loaded_layers

Python Kit Commands

import omni.kit.commands


omni.kit.commands.execute("CreateSublayer",
    layer_identifier=stage.GetRootLayer().identifier,
    # This example prepends to the subLayers list
    sublayer_position=0,
    new_layer_path=r"C:/path/to/sublayer.usd",
    transfer_root_content=False,
    # When True, it will create the layer file for you too.
    create_or_insert=True
)