I want to be able plug an undetermined number of meshes (that are placed inside a level in UE4) into an hda. After that I want the hda to do something with the transforms (location, rotation, and scale in UE4) of these meshes.

So in two questions:
How do I set up an hda parameter for the (static mesh) actor input so that I can add an undetermined amount of actors?

How do I get the unreal world transform values for these actors?

I don't think there's a way to do it at the moment. There's no way to input the points with transforms, only geometry / curves.

DASD, only way to do this I can think of is, have a blueprint which dumps your points / transforms into a json / csv file and have a Houdini asset which takes that file.

Alright thanks! I solved it with blueprints.
Also another solution I could think of would be to have the same object in the Houdini Tool and calculate the difference of position based on the first 3 points.

The Unreal plugin has a new input type called “World Outliner Input”. With this, you can input multiple Actors from the scene into a single input on the asset. What this does in Houdini is create a Merge SOP that puts together all the input meshes from the input Actors and passes it to the asset's input.

Knowing this, you can go back up the input to the asset and find the list of input meshes (which are in their own OBJ nodes) and get their transforms.

Thank you! Very good to know!

damian
The Unreal plugin has a new input type called "World Outliner Input". With this, you can input multiple Actors from the scene into a single input on the asset. What this does in Houdini is create a Merge SOP that puts together all the input meshes from the input Actors and passes it to the asset's input.

Knowing this, you can go back up the input to the asset and find the list of input meshes (which are in their own OBJ nodes) and get their transforms.

Hi, I googled this because Im trying to do the same thing. I don't know how to begin to do what you've described, but it looks like what I need. Could you please elaborate?

solodev

damian
The Unreal plugin has a new input type called "World Outliner Input". With this, you can input multiple Actors from the scene into a single input on the asset. What this does in Houdini is create a Merge SOP that puts together all the input meshes from the input Actors and passes it to the asset's input.

Knowing this, you can go back up the input to the asset and find the list of input meshes (which are in their own OBJ nodes) and get their transforms.

Hi, I googled this because Im trying to do the same thing. I don't know how to begin to do what you've described, but it looks like what I need. Could you please elaborate?

Sorry for necro, but I figured it out with some playing around. You've probably found a solution to the problem (hopefully) but I thought I would chime incase someone like me stumbles upon this post.

Make sure your HDA as a spare input and it's setup to do what you want, in my case Boolean the model.
- In the Sub-Network Input #2 set it to 'World Input'
- It should by Default already be setup to detect the current scene you're in
- Press the 'Start Selection' button, then select the asset from the outliner
- The 'Start Selection' button will have changed to 'User Current', click that
- You should now see it updated with the asset you've chosen

You should be all good to go. Idk if it will work for everything, but it fits what I was looking for.
Good luck.