Houdini 20.0 Unreal

Packaging

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Packaging Houdini Assets

The plug-in provided classes are designed to be cooked and packaged transparently meaning they contain small amounts of code.

The plugin acts as simple data holder which reduces their potential runtime footprints.

In a game build, they're invisible except for their output components ( StaticMeshComponent, Landscapes, etc. ).

If there are HoudiniAssetActors in your maps, the HoudiniEngine plug-in must be built as part of the runtime build of your game.

Baking Outputs

An alternative method is to Bake your Houdini Engine-based assets to Unreal-native actors and remove the HoudiniActors before cooking your content.

This removes the dependencies on the Houdini-Engine plug-in and doesn’t require the game-build of the plug-in.

You can also use the Bake And Replace All Houdini Assets entry in the Houdini Engine menu in Unreal to replace all the Houdini assets in the current level with their baked counterpart.

The Bake Folder (the folder where the baked assets will be stored) is determined by first checking for the unreal_bake_folder attribute on the asset (prim, detail). If this isn’t set then it uses the property in the details panel. If the property is also not set, then it uses the default bake folder configured in the plugin settings.

If you finalize a level this way, you have to manually recreate the Houdini Assets to modify the procedural content again. It’s recommended to use this workflow after you have finalized your content.

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.