Beginner question: How can I expose the spline component?

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Firstly, im using Houdini 21.0 and Unreal 5.6. I have a very rough and simple road creation tool and im trying to figure out how to expose the main curve in unreal as a spline component. Ive looked at documentation and all the videos I can, nothings really working. Ive reduced the complexity of the tool (as there was multiple curves being used) to one curve in hopes to just figure it out from one curve, but nothing yet. Ive used an attrubute wrangler to create an integer with the vex code, which in the documentation states that it will expose it as a spline component in unreal. Im not entirely sure where this attribute wrangler should be placed and anywhere ive placed it so far hasnt really done much. Following older youtube tutorials about curves from houdini to unreal has turned out to be no help as theyre outdated.

Anyone with any knowledge on how to set up an editable curve from houdini to unreal that could drop some knowledge on me. would be extremely appreciated.

(Im new to houdini, I started about a week ago. Ive gone through a lot of the tutorials on the sidefx website. Again, most are slightly outdated for these workflows.)

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The curves sop inside an HDA is a deprecated workflow.

You will need to provide the HDA curves from Unreal using splines in your level. So in Houdini the curve would live upstream and plug into the HDA input.

Then in Unreal, you change your HDA Input to either 'World' if you are using curves from your level. Then select those curves as the input for your HDA. Or you can set the HDA Input to 'Curve', and Houdini Engine provides a base curve you can edit directly in the detail panel as well.

We have some basic set ups for curves in our content examples if you wanted to download and check it out. https://github.com/sideeffects/HoudiniEngineForUnreal-ContentExamples [github.com]
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