The Houdini Unreal Engine plugin allows Skeletal Meshes and Skeletal Mesh components to work with HDAs and NodeSync.
You can learn more about KineFX Skeletons on its documentation.
Install Houdini HDAs for Skeletal Mesh ¶
Import and exporting Skeletal Meshes requires two HDAs loaded into Houdini to work properly.
To install these HDAs:
-
Locate your Houdini Engine plugins folder.
-
Go to the HoudiniEngine\Content\NodeSync folder.
-
Copy KineFXToUnreal and UnrealToKineFX HDA files.
-
Paste these two files into your otls folder. In this example the location is C:\Users\PC\Documents\houdini20.5\otls.
After you install the Houdini plugins, you can follow the instructions on the NodeSync documentation to send Skeletal meshes from Unreal to Houdini and vice versa. Skeletal mesh can also be used in Inputs or created as HDA outputs.
KineFX to Unreal (output) ¶
When working in Houdini, Skeletal meshes use a Rest Geometry and Capture Pose to make changes.
To export the Skeletal mesh back into Unreal properly, you need to use the KineFXtoUnreal node as the final output.
-
Create a KineFXtoUnreal node.
-
Connect your Rest Geometry output into Input1 and the Capture Pose output into Input2.
-
Click CTRL+C to copy the KineFXtoUnreal node.
-
Use the Fetch from Houdini procedures above to import into Unreal Engine.
Using Existing Unreal Skeletons ¶
Skeletal Meshes exported from Houdini to Unreal can use an existing Unreal Skeleton Asset rather than creating a new Skeleton Asset. The unreal_skeleton attribute defines the existing skeleton. When using an existing Unreal Skeleton, a Catpure Pose must still be specified.
Unreal to KineFX (input) ¶
When sending an Unreal Skeletal Mesh to Houdini use the UnrealtoKineFX HDA to unpack the input data to a Rest Geometry and Capture Pose for use with KineFX.
The first output connects to the Rest Geometry and the second output connects to the Capture Pose.
In this example, the Skeletal mesh is now able to be edited using the Joint Deform SOP node.
