How come the result is offset from the curve ?

Well I found this thread:

https://www.sidefx.com/forum/topic/43983/ [sidefx.com]

with this Github bug/issue:

https://github.com/sideeffects/HoudiniEngineForUnreal/issues/61 [github.com]

Im running Unreal 4.12.3 and Houdini 15.5.511 and it is still happening, and if i put the transformations to 0,0,0 and then if I turn “Curve Input” back to “Geomtry Input” and then “Asset Input” and then back to “Curve input” I can get it to snap back to the right locations..

So if it was “fixed” it might be broken again or perhaps never was fixed I dont know.

The issue is that curve inputs are created in world space in Houdini but they are tied to the asset in UE4. This presents a mismatch of how geometry inputs to a SOP asset work. It's a bit of a workflow issue, for sure, that should be fixed at some point. Unfortunately, that's not trivial to do at this point.

There is a relatively simple workaround that should fix this issue. You have to change your asset to be an OBJ asset.

You can do this by marking your instantiated SOP asset as editable and then creating a new asset out of the OBJ that contains your SOP. For each of your SOP inputs, you have to create an Object Merge SOP for which you expose the Object 1 parameter to the top level of your new asset. For curve inputs, you have to make sure the Transform parameter on the Object Merge SOP is set to None.

Well I already have a working workaround, but it's sad that simple things like this dont work as expected. Would it be possible to get a HDA example of what you descrived because it would help alot.

Yep, see attached asset. It contains an Object Merge node that has its Object 1 parameter exposed at the asset level as “Curve”. In UE4, this becomes a Houdini Input called “Curve” that accepts curves and correctly moves the curve and the end result mesh with the asset transform.

The attached asset also has a default curve that is used if no input curve is given.