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Houdini Engine for Unreal uses a headless version of Houdini meaning an internal Houdini scene is running in the background hidden from the user.

Houdini Engine manages an internal Houdini scene when:

  • a Houdini asset is instantiated in Unreal

  • you connect input geometries from Unreal to the Houdini asset, the Unreal geometry is marshalled to Houdini in an Input node

  • asset parameters set in Unreal are mirrored in the Houdini scene

  • manipulators like curves and handles are replicated and linked to the Houdini scene

  • geometries from the Houdini asset outputs are replicated into Unreal.

Debugging Workflows

At times, you may want inspect the internal Houdini scene when an assset doesn’t behave as expected.

These three methods launches or saves the current internal Houdini scene and allows you to debug any issues on the Unreal asset. It’s also useful to see the data and metadata available in the Houdini scene.

There are three methods to debug your assets:

  1. Open the scene in Houdini

  2. Save out a .hip file

  3. Use Session Sync


All three methods require a Houdini license to run a Houdini UI version.

Open scene in Houdini

This method opens the current internal Houdini scene in a new Houdini application.

  • In the Houdini Engine menu in Unreal, select Open Scene in Houdini.

A new Houdini application lauches with the internal Houdini scene.

Save out HIP file

This method saves out the current internal Houdini scene to a .hip file.

  1. In the Houdini Engine menu in Unreal, select Save Houdini scene (HIP).

  2. Save the file.

  3. Open the .hip file in your Houdini application.

Use SessionSync

This method creates a sync and allows you to send iterations between Houdini and Unreal.

You must be connected to a SessionSync session. See Start a SessionSync documentation.

  1. In Unreal’s Content Drawer, select your HDA asset.

  2. Right click your asset, and select Instantiate at the origin.

  3. Your asset now appears at the origin of Houdini.


Getting started


Using Houdini Engine


Houdini Engine for Unreal Engine is a plug-in that allows integration of Houdini technology into Unreal. Session Sync and Node Sync are two features of the Houdini Engine Plugin to interact with a live session of Houdini.

This plug-in brings Houdini’s powerful and flexible procedural workflow into Unreal Engine through Houdini Digital Assets. Artists can interactively adjust asset parameters inside the editor and use Unreal assets as inputs. Houdini’s procedural engine will then “cook” the asset and the results will be available in the editor without the need for baking.

General information:


Currently, the plugins has binaries that have been built for UE5.3, 5.2, 5.1, 5.0, UE4.27 and UE4.26, and is linked with the latest production build of Houdini.

Source code for the plugin is available on this repository for UE5.3, 5.2, 5.1, 5.0, UE4.27, UE4.26.


UE5.1 and UE5.0 use the same source files/branches, the 5.0 sources are also intended to be used with 5.1.

Support and reporting bugs:


The Houdini Engine SessionSync feature allows you to connect to a session of Houdini Engine running inside Houdini with its GUI. It supports all the features of the regular Houdini Engine workflow and additional features specific to Session Sync.

Houdini Engine uses a non-UI version of Houdini while Session Sync lets you see and interact with the Houdini session through Houdini’s user interface. It also synchronizes changes made in either Unreal or Houdini so both programs can make changes and see the same results.


NodeSync is a feature for the Houdini Unreal Engine Plugin that enables sharing assets between Unreal and Houdini Session Sync. It works for Skeletal and static meshes.

You can send and receive data to and from Unreal without a dedicated HDA. It works with Static and Skeletal meshes as well as Actors.

Houdini Niagara

The Houdini-Niagara plugin allows you to exchange point cloud data between Houdini and Unreal’s Niagara system using the HoudiniNiagara Data Interface. You can export Houdini’s attribute data as HoudiniPointCache assets. These can then be imported into Unreal to use the Niagara systems and emitters to create complex effects and particle systems.