Hello all;

I'm working on some procedural environment creation tools using Houdini Engine, Unreal, and Substance.

The first ‘proof of concept’ tool creates small islands for a swamp-type environment, based on a user-generated spline curve in Unreal.



I also have a substance graph that generates plausible textures for any mesh the .hda produces, and I'd like to automatically generate the textures (using substance) without leaving Unreal, or manually tracking exported meshes.

The ideal workflow would look like this (everything apart from the spline creation happening automatically):

Draw spline > Generate high-res mesh > generate low-res mesh > bake utility maps for substance graph > feed maps into substance factory > generate final textures from .sbsar > apply final textures to material instance

I have each of these steps working independently, but it seems that it's not possible to wrap substances, or baking tools, inside a .hda. Manually exporting and tracking 50+ hi/lo-res meshes is going to be a pain.

Potential approaches:

1. Have sbsbaker.exe packaged as part of the .hda
Problem: Currently not possible with the current version of Houdini Engine, maybe not ever

2. Execute ‘GameDev Simple Baker’ from within Unreal, and import the resulting maps
Problem: Doesn't work from within Unreal (maybe because Houdini Engine for UE4 is lacking mantra?)

3. Automatically export high / low-res meshes from Unreal, and call Substance Automation Toolkit to bake the required maps using python
Problem: Might be possible to call .sbsbaker (through python) from within HE, but the meshes would have to be exported from Unreal automatically, which I don't think HE can do.


I assume a lot of people have tried to do this - am I missing something? If it's not currently possible, where is the smart money on the workflow that would turn up first?

Many thanks for the help

Hi there, stumbled on the same issue. Did you ever get any answer to this?

Hi I'm working towards a similar workflow to your option 2. but for a prop type asset. I didn't realise that Houdini Engine wouldn't be able to do the baking and I'm hoping someone has a workaround for this since it seems like the most streamlined workflow.

No - I haven't made any progress since my post in December.

Speaking to some programmer friends of mine, consensus seems to be my method #3 is the most likely, but probably requires some code that currently beyond my ability to create.

having the same issue - not with unreal - but with cinema4d - when it comes to baking i think because of this cooking workflow houdini engine isnt capable of baking maps (or at least with the gamedev toolkit)

hope you proof me wrong

You should normally be able to use the simple baker in UE4.

As with any ROP, you however need to add that node to the editable node list of the HDA (in the type properties).
Clicking the button actually modifies the node, and that requires it to be editable.

The simple baker is a little more complex, since it has multiples ROPs (Some of them already editable), but you actually need to add the simple baker sop to the editable nodes of your HDA, as well as the ropnet inside it. (and the rop_fbx if you intend to use it)

That being said, we found a bug last week with the simple baker SOP that confuses Houdini Engine / HAPI and makes it ignore the output geometry.
But once it's fixed, the simple baker SOP could be used in HE plugins (as long as the relevant node are marked as editable).

There is a Substance plug-in for Houdini.https://forum.substance3d.com/index.php/board,47.0.html?PHPSESSID=e89a1efca9e26982c5876c87424b591f [forum.substance3d.com]
Last time I checked it was not ideal. It is maintained by the Substance people and really needs some love.
Has anyone tried it recently? Has anyone tried it in combination with Houdini Engine?

There’s some work being done on a new version of the plugin that will run in COPs. We should have some more info to share in about a months time.

Mike