Houdini 20.0 Unreal

Content examples overview

On this page

The Houdini Engine for Unreal content examples contains showrooms that demonstrate features within the plugin. Each showroom has a small example to help you quickly understand a topic either through educational information or a simple action walkthrough.

Each level contains a specific topic such as:

Here’s an example of a curve showroom on the subtopic Scatter on Surface. It provides instructions to edit the curve spline and change a few parameters to see the results on the platform.

Scatter on Surface showroom example

Installing content examples

  1. Download the latest Houdini Engine for Unreal content examples on the Houdini Engine for Unreal Content Examples Github repository.

  2. If you don’t have the Houdini Engine for Unreal plugin, download it on the Houdini Engine for Unreal Github repository. You can also follow the Install Houdini Engine for Unreal instructions.

  3. In the HoudiniEngineForUnreal-ContentExamples-main folder, create a Plugins folder.

  4. In the Plugins folder, paste the HoudiniEngine folder from the Houdini Engine for Unreal plugin.

  5. You should now be able to launch the HEngine_Examples.uproject in the Windows Explorer or Epic Launcher’s library.

Note

For Unreal Engine 5.0 and 5.1, you must use Unreal’s project directory.

Troubleshooting

  • If you get the following error: The following modules are missing or built with a different version.. Would you like to rebuild them now? Select Yes. This should rebuild the source.

  • If you get the following error: HEngine_Examples could not be compiled. Try rebuilding from source manually.

    • You may be missing Visual Studio and Windows SDK components. In the HoudiniEngineForUnreal-ContentExamples-main folder, check Saved\Logs folder for any error logs that will indicate which missing components are needed.

Getting started

It’s recommended to begin in the Starter Map as it explains how the levels and showrooms work. The first time you open these maps, you may need to cook the HDAs to see the geometry and assets.

  1. In the \Content\ContentExamples\Maps folder, open the ContentExamples_StarterMap.umap

  2. In the Houdini Engine main menu, select Create Session. You should see a confirmation at the bottom right stating Houdini Engine session is connected.

  3. In the Houdini Engine main menu, select Rebuild All. This may take a few minutes for larger maps.

The other topic maps are also located in the \Content\ContentExamples\Maps folder.

Using HDAs in Houdini

In the \Content\ContentExamples\ folder, you can see topic folders such as Curves, Geometry, and Instancers. Within these folders, you can open the HDAs in Houdini to further dissect the node networks, attributes, and parameters.

At the object level, you can see the node network with notes explaining the workflow, attributes, and parameters used for the HDA.

Edit HDA examples

To edit the HDA and re-export to Unreal:

  1. Right-click the HDA node at the geometry level and select Allow Editing of Contents. You will see the node unlock.

  2. Make any edits to the nodes

  3. In the HDA’s geometry level, right-click the HDA node and select Digital Asset then Save Copy As.

  4. Left-click drag your HDA file into the content browser. Your HDA file should appear as a HoudiniAsset.

  5. Left-click drag your HoudiniAsset into the viewport.

  6. In the Houdini Engine main menu, select Rebuild All. You should now see your updated HDA changes.

Unreal

Getting started

Basics

Using Houdini Engine

Reference

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:

Compatibility:

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.

Note

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:

SessionSync

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

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.

The Houdini KineFX Live Link plugin lets you control rigs in Unreal directly from KineFX in Houdini.