How/whether to edit the stage population mask.

When Populate primitives is “Add and Remove” or “Set Primitives”, this is a list of primitive path patterns matching prims to include. The difference between this and Populate paths is that this parameter selects from prims that exist in the input.

When Populate primitives is “Add and Remove”, this is a list of primitive path patterns matching prims to remove. Removing a primitive from the stage population mask means the resulting primitives will no longer exist in the output stage. The difference between this and Depopulate paths is that this parameter selects from prims that exist in the input.

When Populate primitives is “Add and Remove” or “Set Primitives”, this is a list of explicit paths (no patterns allowed) of prims to include. The difference between this and Populate input paths is that this parameter can add paths to the mask even if this node has no input, and even if the prims don’t exist at the paths yet, but might be created by subsequent nodes.

When Populate primitives is “Add and Remove”, this is a list of explicit paths (no patterns allowed) of prims to remove. Removing a primitive from the stage population mask means the resulting primitives will no longer exist in the output stage. The difference between this and Depopulate input paths is that this parameter can remove paths from the mask even if this node has no input, and even if the prims don’t exist at the paths yet, but might be created by subsequent nodes.

How/whether to edit the set of primitives which should load their payloads.

When Load primitives is “Add and Remove” or “Set Primitives”, this is a list of primitive path patterns matching prims to load. The difference between this and Load paths is that this parameter selects from prims that exist in the input.

When Load primitives is “Add and Remove”, this is a list of primitive path patterns matching prims to remove. Removing a primitive from the set of payloads to load means the resulting primitives will no longer compose their payload arcs on the output stage. The difference between this and Unload paths is that this parameter selects from prims that exist in the input.

When Load primitives is “Add and Remove” or “Set Primitives”, this is a list of explicit paths (no patterns allowed) of prims to include. The difference between this and Load input paths is that this parameter can add paths to the set even if this node has no input, and even if the prims don’t exist at the paths yet, but might be created by subsequent nodes.

When Load primitives is “Add and Remove”, this is a list of explicit paths (no patterns allowed) of prims to remove. Removing a primitive from the set of payloads to load means the resulting primitives will no longer compose their payload arcs on the output stage. The difference between this and Unload input paths is that this parameter can remove paths from the set even if this node has no input, and even if the prims don’t exist at the paths yet, but might be created by subsequent nodes.

How/whether to edit the set of muted layers.

When Mute layers is “Add and Remove” or “Set Layers”, this is a list of paths to layers to mute. Even if the layers listed here do not exist on the inputs stage (if any), this set of paths will be remembered by the stage, and loading of the named layers will be prevented in subsequent nodes.

When Mute layers is “Add and Remove”, this is a list of paths to layers to unmute (if they are currently muted).

A path to a file containing configuration information for the asset resolver. The standard USD asset resolver and Houdini’s built-in asset resolver do not use this, but if you use a custom asset resolver, it may read this file to change its settings when loading layers for this stage. This parameter only affects the USD stage if this node has no input connected.

The contents of this file, whether it is used at all, and if it’s used, how it affects the behavior of the asset resolver, is completely up to asset resolver implementation.

For example, the configuration file might specify a version number, telling the resolver to prefer assets of that version when loading resources.

The resolver context can be configured using multiple separate strings. Each string is used to configure one resolver. One string (with no URL prefix specified) is sent to the default resolver used for all asset paths that are not in URL format. Other strings can be paired with a URL prefix to configure the resolver associated with that prefix.

If there is at least one non-empty resolver context string value provided, this takes precedence over any resolver context asset path, and the resolver context for the LOP stage will be created using the ArResolver::CreateContextFromStrings method instead of ArResolver::CreateDefaultContextForAsset.

Configures what variant selection fallback values to use for specific variant sets when no explicit variant selection opinion is provided on a prim. These fallbacks are applied on top of any global variant selection fallbacks configured using the USD library plugin mechanism, and on top of any variant selection fallbacks configure on the LOP Network.

Every USD layer can contain a dictionary of “stage variables” as metadata onthe root primitive. These stage variables can be referenced in asset path attributes, composition arcs such as references, and in variant selections.

For each stage variable, the name of the variable.

For each stage variable, the data type of the variable value.

For each stage variable, the value to associate with the name.

(Behind the scenes there are several different parameters (stagevariablestrvalue‹n›, stagevariablefloatvalue‹n›, stagevariableintvalue‹n›, stagevariableboolvalue‹n›) all labeled Stage variable value, with the visible one controlled by the Stage variable type value. This may be relevant if you are using expressions or scripting these values.)