Because internal names must be unique, and simple names might collide (with existing or future factory node names, or names of assets from other users or other studios), you can add a namespace and/or a version to the name. We recommend you add at least a namespace to the assets you create.

For more information, see namespaces.

In the Create Asset dialog, the main part of the namespace is labeled Author, because you should generally specify the creator of the asset (either your name or the name of your studio) to distinguish it from assets created by other people/studios.

If $HOUDINI_DEFAULT_ASSET_NAMESPACE is set, Houdini uses it as the initial default. It that is not set, it uses the value returned by hou.userName() (this is the user name portion of $HOUDINI_AUTHOR if it is set, otherwise the current user name). See asset creation environment variables below for more information.

The drop down list for the Author field includes:

• The values of $HOUDINI_DEFAULT_ASSET_NAMESPACE (if set).

• The value returned by hou.userName().

• Any presets you've configured.

• Any namespaces/authors found in the names of existing installed nodes.

If you have assets in various phases of development being used by different people in a studio (for example, artists are using a “finished” asset but Technical Directors are beta-testing the next version of the asset), you can add an extra bit of structure to the namespace indicating which development “branch” the asset is in.

This lets you have different “branches” of an asset with the same Author and Version installed at the same time. For example, a “dev” branch (acme.dev::myasset::1.0) and a “test” branch (acme.test::myasset::1.0).

In the dialog, Houdini considers anything after the last delimiter in a namespace to be the “branch”, where a delimiter is one or more . (period) or : (colon) characters. So, for example, an asset with the namespace foo.bar.baz will be considered to have an Author of foo.bar and a Branch of baz. We recommend that you use the default . (period) as the delimiter to make it easier to tell the namespace part from the rest of the full name. However, studios may have legacy policies to use : or :: as the branch delimiter. You can change the delimiter by editing the full name in the Internal name field.

Houdini starts with a few preset branch names for you to use. You can add to, edit, or remove them (see configuring presets).

The drop down list for the Branch field includes:

• The current default branch.

• The configured presets.

• Any branches found in the names of existing installed nodes.

The base name should describe what the node does. We recommend that the core name be at least similar to the label, so it’s easier to tell which node type corresponds to the label that users see.

Adding a version to the asset name lets you have separate version of an asset with the same Author and Core Name. This lets create a new version with added functionality to an asset, a different parameter interface, and so on, without affecting existing instances that use the previous definition version.

When multiple versions of an asset are installed, by default the Tab menu will put down the latest (highest numbered) version. However, instances of previous versions can still exist in HIP files and will still work.

Even if you don’t add a version number to an asset when you create it, you can create a new version of the asset later by adding a version number to the name. For example, you can go from acme::myasset to acme::myasset::2.0.

For more information, see asset name version and systems for versioning assets.

The Location menu contains the following commonly used locations, plus any other hda or otls directories found on the Houdini Path, and any additional save location presets you've configured.

If the Location is not Custom File Path, you can choose the naming scheme Houdini uses to generate the library filename to save the asset into. See file naming schemes below for more information.

You can also choose to prefix the file name with the network category type (for example, sop, lop, object). We recommend you do this to avoid collisions between assets in different categories with the same name.

Houdini automatically finds assets at startup by looking in hda and otls sub-directories on the Houdini Path (see about the Houdini Path).

(For historical reasons, Houdini looks for assets in both HOUDINIPATH/hda and HOUDINIPATH/otls.)

When you save an asset, you usually want to save it into an hda sub-directory on the Houdini Path. This ensures Houdini will find and install the asset automatically when it starts up.

• When you save the asset, Houdini will automatically re-scan for assets, so Houdini will automatically install the asset if you saved to an hda or otls sub-directory on the Houdini Path.

• If the save location is not on the Houdini Path, Houdini will install the asset for use in this session. However, the next time you start Houdini, it will not find the asset on the path and to use it you will need to manually install it using Assets ▸ Install Asset Library.

If the save location is Embedded, Houdini will save the asset as part of the current HIP file, instead of in a separate file.

This can be useful sometimes:

• If you are just experimenting with an asset and don’t want to commit it to disk yet.

• If you want to share a working HIP file with someone else who might not have their own copy of the asset installed.

However, for general use embedding has drawbacks:

• The asset is only available in that HIP file. It can’t be shared between projects or users.

• Saving the asset as part of the HIP file bloats the size of the HIP file.

Unless you are embedding an asset for a specific reason, you should usually save it to a file

If the Location is not Custom File Path, you can choose how Houdini constructs the library file name to save in the chosen directory using the File Naming Scheme menu. Houdini provides the following naming scheme choices:

You can use the following variables in the custom pattern, either in $NS or ${NS} form:

A studio can disable this option and enforce a standard filename pattern by setting the $HOUDINI_ASSET_FILENAME_PATTERN environment variable. See asset creation environment variables for more information.

You can use configuration files to provide site-wide or studio-wide presets.

The Create Asset dialog stores its configuration in $HOUDINI_USER_PREF_DIR/vhda.config. This is a simple JSON file. When it loads the configuration at start-up, it looks for vhda.config files in each directory on the $HOUDINI_PATH and merges them.

Note that, in Houdini, earlier directories on the path override later directories. The user prefs dir is usually near or at the start of the path, but packages are earlier.

Since “earlier” values override “later” values in configuration files on the path, plain values (such as the default Author string) in the user prefs will usually override any site-wide values you have later in the path (unless you hack the user’s configuration file to not have a certain key and then prevent it from being overwritten).

However, for list values, the dialog merges together all the lists it finds in the configuration files on the path. This lets you specify site/studio-wide Author, Branch, and Save Location presets that will be added to any presets each user has in their own configuration.

For example, a studio might have Houdini set up so the directory /mnt/server/houdini/sitewide/ is in the Houdini path, and is used for site-wide configuration.

You could create the following JSON file at /mnt/server/houdini/sitewide/vhda.config:

{
    "users": ["acmeSF", "acmeNY"]
}

This will add acmeSF and acmeNY to the drop-down list of preset authors (for historical reasons, the config key for the Author field is called users).