Damien Pernuit


About Me



Recent Forum Posts

Houdini Engine for Unreal - Version 2 Released! Jan. 19, 2021, 7:03 p.m.

Hi everyone,

It's with pleasure that I'd like to let you all know that today's production build of Houdini (18.5.462) has the official release of Version 2.0!

The source code (for UE4.26, 25, 24 and 23) is also available on the git repository:
https://github.com/sideeffects/HoudiniEngineForUnreal-v2 [github.com]

Binaries for Unreal 4.25 and 4.26 can also be downloaded on the git repository's release page
https://github.com/sideeffects/HoudiniEngineForUnreal-v2/releases/tag/v2.0 [github.com]

The Documentation [www.sidefx.com] on the website has been updated to cover all the changes made in version 2.0.

Here are some of the new features and improvements that were made in Version 2.0:

- New and redesigned core architecture, more modular and lightweight.
All the Houdini Engine/HAPI logic is now Editor-only and contained in the “HoudiniEngine” module. All the custom runtime components and actors used by the plugin now simply acts as data-holders, and are processed by the HoudiniEngine modules, removing the need to bake HDA before packaging a game.
- The plugin now relies exclusively on native, UProperties based serialization, so operations like cut and paste, move between level, duplicate etc.. do not exhibit any of the issues that version 1 had with those operations.

- Static Mesh creation time has been optimized and now uses Mesh Descriptions.
- Alternatively, you can also decide to use an even faster Proxy Mesh generation while editing the HDA.
  Those can then be automatically refined to Static Meshes, either on a timer, or when saving/playing the level.
- World composition support: Tiled heightfields can now be baked to multiple landscape actors/steaming proxies, and will create/update the levels needed for world composition.
  You can specify the level's path by using the new “unreal_level_path” attribute, that is also used by meshes and instancers so they can also be baked out to separate levels.
- Material overrides and generic uproperty attributes can either be applied on the instancer, or per instance (when using mesh split instancers or instanced Actors).
- It is possible to create foliage instances directly, without baking, when using the “unreal_foliage” attribute on an instancer.
- A class can be directly instantiated by the "unreal_instance" attribute (ie “PointLight”, “AudioVolume”… ).
- Curves can be outputed to SplineComponents by using the "unreal_output_curve" primitive attribute.


- Colliders on a Static Mesh can now be imported as group geometry.
- World inputs can now read data from BSP brushes.
- Instancers and Foliage are now imported as packed primitives.
- World inputs have an improved bound selector mode, that lets them send all the actors and objects contained in the bounds of the selected object.
- World inputs can now import data from all supported input objects (landscape, houdini asset actors..)
- World inputs can now import data from actors placed in a different level than the Houdini Asset Actors's.
- A single curve input can now create and import any number of curves.
- You can alt-click on curve inputs or editable curves to create new points.
- HDA parameters and inputs editing now support multi-selection.
- Parameter UI/UX has been improved:
- Folder UI (tabs, radio, collapsible) has been improved
- Ramps UI has been improved, and it is easy to turn off auto-update while editing them.
- When an asset is dropped on a string parameter, it automatically sets its value to the asset ref.
- String parameters can now be turned into an asset picker via the “unreal_ref” tag.
- Support for File parameters has been improved (custom extension, directory, new file...)
- Multi-line strings, Column Labels, Button Strip, Log Int and Floats are now supported.

- The plugin's UI has been completely revamped, a new Houdini Engine menu has been added to the editor.
- bgeo/bgeo.sc files can be imported natively in the content browser (Mesh and instancers).
- The PDG Asset Link has been added, allowing control of TOP networks nested in HDAs, and works similarly to the one in the Unity plugin.
- Session Sync is supported, allowing the plugin to connect to a session of Houdini Engine running inside Houdini.
  The state of Houdini Engine can be viewed in Houdini while working with the plugin in Unreal, and changes on either end, whether in Unreal via the plugin or in Houdini via its various interfaces, will be synchronized across so that both applications will be able to make changes and see the same results.
- Blueprint support: It is now possible to use Houdini Asset Components in the Blueprint Editor.
This lets you preset and use HDAs on Blueprint Actors, and changing parameters/inputs on the Houdini Asset will automatically update all placed instances of that Blueprint.

We'll be spending time in the coming weeks polishing the plugin and all the new features and workflows that were added in v2.

As for what's coming next, I'll be updating this post soon with a roadmap of all the new features that are currently planned for the plugin.

A huge thanks to all the Alpha and Beta users who have given us feedback and reported issues during the development of V2!

Creating Curve/Curve atlas in hda? Jan. 19, 2021, 6:37 p.m.


We don't support those in the plugin, the only type of "curves" supported by the plugin are SplineComponents, that will be created as curve SOPs in Houdini.

The HoudiniColorRampCurve/FloatRampCurve are the curve object used for Color/Float ramp parameters.

Houdini Engine for Unreal - Version 2 Jan. 19, 2021, 6:23 p.m.

@JvK Artwork / @ChinaNoodles : This issue should have been fixed in recent builds of the plugin.

@adipamihi : Landscape edit layers arent supported by the plugin, simply because they were added to unreal fairly recently, and the plugin's landscape portion was already completed at the time.
We do have a few RFEs for it, and they will likely be one the first feature we'll tackle after the v2 release.
(stay tuned for the roadmap)

@Josich : Hard to tell what's causing the issue just looking at the screenshot, but materials should be support similarly in both v1 and v2. Please submit a bug report for that and send us your HDA so I can have a look.

@sggvideo : Thanks for bringing this up, v2 was indeed shipping with the old VAT materials, this should be fixed on git, and will be in tomorrow's daily build.
Alternatively, you can just copy them from the git repo:
https://github.com/sideeffects/HoudiniEngineForUnreal-v2/tree/Houdini18.5-4.26/Content [github.com]

You need the Materials and MaterialFunctions folders.