Hey guys, I'm having a pretty detrimental issue with Houdini Engine v2 right now.

I'm working on a large-scale environment processing tool for a project, for which I'm using PDG and world composition functionality in Unreal Engine. I've already had a lot of bugs and crashes with the earlier betas of HEv2, but the latest build ironed some of those out.

Now, I've done a week of extensive testing and I can't figure this one out: Whenever I try to bake my environment into world composition levels (using the 'Unreal World Composition Prepare' node), either the levels don't show up at all or they show up without the landscape / heightfield component. I'm following a somewhat similar setup to the Procedural Desert tutorial by Simon Verstraete.

I've tested this in a normal SOP-level HDA as well and with a simple setup, that one works fine. I've ruled out the possibility of it having to do with incompatible resolutions (the SOP example uses the exact same 4033x4033 heightfield) or any incorrect attributes (again, exact same as the SOP HDA).

Anyone with the same issue, or is this a known bug?

JvK Artwork
Hey guys, I'm having a pretty detrimental issue with Houdini Engine v2 right now.

I'm working on a large-scale environment processing tool for a project, for which I'm using PDG and world composition functionality in Unreal Engine. I've already had a lot of bugs and crashes with the earlier betas of HEv2, but the latest build ironed some of those out.

Now, I've done a week of extensive testing and I can't figure this one out: Whenever I try to bake my environment into world composition levels (using the 'Unreal World Composition Prepare' node), either the levels don't show up at all or they show up without the landscape / heightfield component. I'm following a somewhat similar setup to the Procedural Desert tutorial by Simon Verstraete.

I've tested this in a normal SOP-level HDA as well and with a simple setup, that one works fine. I've ruled out the possibility of it having to do with incompatible resolutions (the SOP example uses the exact same 4033x4033 heightfield) or any incorrect attributes (again, exact same as the SOP HDA).

Anyone with the same issue, or is this a known bug?

yeah, I have the same issue. I'm using UE 4.26 and compiled the latest houdini engine (with 408) by myself. when you bake out something, if it have some meshes or instances. it can generate the sublevel but without heightfield. Basically it can't bakeout the heightfield at all by using pdg.

Prefacing this with the disclaimer that I use Houdini and UE4 as a hobbyist, so the requested capability might not be as useful as it sounds in more complex pipelines.

Context:
UE has some interesting things going on at present with landscape edit layers as well as Epic’s landmass plugin (as seen with the new water system in 4.26).

Landmass reads in the height data and can output changes to the landscape as a layer in a non destructive way.

RFE:
Ability to export height-fields as a layer to landscapes.

Ideally I would like to be able to have this workflow.

1. Define the base massing model / blockout of the landscape within UE’s landscape tools. I could also use landmass tools (such as the 4.26 Water system or my own custom designs) onto this landscape.

2. Import the landscape into Houdini as a heightfield (this is already possible) and apply erosion.

3. Export the eroded terrain as a layer onto an existing landscape within UE (so for example in this case as a new layer onto the input landscape).

Current issues:
Currently the only reasonable ways to continue with applying manual changes to the landscape is to unhook it from Houdini (by cooking it as a base mesh).

The Houdini integration isn’t built with back and forth changes to the landscape in mind so its not safe to apply manual changes (or automated processes within UE via Landmass) onto this terrain as it could be lost when rebuilding the HDA.

Other advantages of this RFE:
The key advantage is being able to apply an erosion HDA into a terrain that is defined in UE.

Another would be that you could theoretically apply multiple terrain HDAs onto a single landscape.

For example I could apply a secondary HDA to raise/lower areas of the landscape for foliage or roads and bring these results into UE as a layer.
As it is a layer I can go back and forth non destructively without having to worry about losing manually painted terrain details on another layer.

It would also be possible to create an HDA at the end of my pipeline to generate layer infos for landscape material and foliage purposes.

Since this happens at the very end it would correctly identify slopes and other features on the terrain that might have been manually painted on top of the original eroded terrain.

==

I'm curious to know other people's thoughts on a feature like this. With my brief examination of the plugin I did not see anything that is a significant blocker in making something like this possible.

@JvK Artwork and @ChinaNoodles I think the best way is to submit the bug with an example HDAs. That will helps the squeaky wheel to get some oil.


Hey @adipamihi, it's interesting to hear what workflows people have regarding landscapes. Is there a need for you to use unreal landscape tools? Anything missing in Houdini? After sculpting terrain in Unreal you can export to file and import it in Houdini as a layer on top. You would only need to calculate the delta between sculped and unsculpted terrain. Some time ago I wrote a tool to speed up some terrain workflows: https://www.youtube.com/watch?v=ArqavvTEFgs [www.youtube.com] check it you maybe that will give you some ideas
Probably for those type of discussion best thing to do will be to create a separate topic

Hi,

I would like to share an issue I'm having with HoudiniEnginev2.

I did an HDA that basically fractures objects but I just realised that in Houdini Engine 2 the materials are lost something that didn't happened in the first version. ( here a couple of screenshots).

The one without textures is using the same HDA the unique difference is Houdini Engine v2


Any workarround or clue?

Many Thanks,

Oscar

Did we lose VAT (vertex animated material) function in the V2 plugin? Just switched from 4.25 w/ v1 to 4.26 w/ v2 and the vat material functions broke, also can't seem to drop in a new material function.

edit: I see the uassets in the Content/Materials folder. hmmm

Hi sggvideo, you can copy it back from V1 it's just a material function. Go to V1 plugin folder and you will find it there.

hektor
Hi sggvideo, you can copy it back from V1 it's just a material function. Go to V1 plugin folder and you will find it there.

Got it, thanks!

@JvK Artwork / @ChinaNoodles : This issue should have been fixed in recent builds of the plugin.

@adipamihi : Landscape edit layers arent supported by the plugin, simply because they were added to unreal fairly recently, and the plugin's landscape portion was already completed at the time.
We do have a few RFEs for it, and they will likely be one the first feature we'll tackle after the v2 release.
(stay tuned for the roadmap)

@Josich : Hard to tell what's causing the issue just looking at the screenshot, but materials should be support similarly in both v1 and v2. Please submit a bug report for that and send us your HDA so I can have a look.


@sggvideo : Thanks for bringing this up, v2 was indeed shipping with the old VAT materials, this should be fixed on git, and will be in tomorrow's daily build.
Alternatively, you can just copy them from the git repo:
https://github.com/sideeffects/HoudiniEngineForUnreal-v2/tree/Houdini18.5-4.26/Content [github.com]

You need the Materials and MaterialFunctions folders.

Anyone else having trouble with terrain since using v2? I did some work with it in v1 but now just adding a landscape input into an erosion node is enough to get an error message upon rebuilding. Also all the old HDAs I made don't work either when there's erosion involved.

Weirdly, opening the HIP file in Houdini from within UE4 (nice feature btw) I can see the result of the erosion and it looks fine. It just doesn't appear in UE4.

Did something change in the setup?


Cook Results:
Geo (ID: 5178): /obj/terrain/terrain1
No geometry generated!


Cook State:
Ready with Cook Errors


===================================
Node Errors, Warnings, and Messages
===================================

/obj/terrain/terrain1/heightfield_erode1/solve_erosion/d:
Error: /obj/terrain/terrain1/heightfield_erode1/solve_erosion/d/s: Error cooking SOP /obj/terrain/terrain1/heightfield_erode1/solve_erosion/d/s/output1:
Error: Invalid source /obj/terrain/terrain1/heightfield_erode1/solve_erosion/d/s/evaporate/blur_drops/terrain_layer1/foreach_end2

etc.....

Hi,

Just tried on my side with a simple HF input + Noise + Erosion + timeshift setup and didn't run into any issue.
Please submit a bug report to support with your hda so I can take a look at your setup.

Hi dpernuit thanks for reply!

Weirdly I was just prepping the scene for upload and somehow it's just started working now. I just put a switch in there to choose between the input of a heightfield in Houdini or the Landscape in ue4 to see the difference.

What was happening is when I chose the Houdini heightfield it would work ok, but when I used the landscape from ue4 it was giving the error. In ue4 I was using a painted terrain layer called 'Base' (with some road splines writing into that layer also) And then in Houdini using that as a mask to stop 'stuff' happening there. Since I put the switch in though it's started behaving itself

I'll put some screenshots to give an idea though.

1) The Houdini graph, 2) input terrain and 3) processed terrain

Aten
What was happening is when I chose the Houdini heightfield it would work ok, but when I used the landscape from ue4 it was giving the error. In ue4 I was using a painted terrain layer called 'Base' (with some road splines writing into that layer also) And then in Houdini using that as a mask to stop 'stuff' happening there. Since I put the switch in though it's started behaving itself

I think it's probably because HoudiniEngineUE4 doesn't support Landscape Layers currently.

Hello,

I reported an issue on git and I would like to know if it's a known issue?

https://github.com/sideeffects/HoudiniEngineForUnreal-v2/issues/121 [github.com]

The problem is basically that when I input a terrain with a scale, the output doesn't get the same scale after passing in my houdini tool. (which does nothing)




In my houdini tool I don't do anything:




Thanks

Hi,

@pouke: Yes, that issue should be fixed in the latest update/prod build (18.5.532)

I am having this same issue and haven't been able to use v2 with anything that has erosion. I have tried using freeze at frame and time shift and they both give the same error. The same HDA works on v1.

Aten
Anyone else having trouble with terrain since using v2? I did some work with it in v1 but now just adding a landscape input into an erosion node is enough to get an error message upon rebuilding. Also all the old HDAs I made don't work either when there's erosion involved.

Weirdly, opening the HIP file in Houdini from within UE4 (nice feature btw) I can see the result of the erosion and it looks fine. It just doesn't appear in UE4.

Did something change in the setup?


Cook Results:
Geo (ID: 5178): /obj/terrain/terrain1
No geometry generated!


Cook State:
Ready with Cook Errors


===================================
Node Errors, Warnings, and Messages
===================================

/obj/terrain/terrain1/heightfield_erode1/solve_erosion/d:
Error: /obj/terrain/terrain1/heightfield_erode1/solve_erosion/d/s: Error cooking SOP /obj/terrain/terrain1/heightfield_erode1/solve_erosion/d/s/output1:
Error: Invalid source /obj/terrain/terrain1/heightfield_erode1/solve_erosion/d/s/evaporate/blur_drops/terrain_layer1/foreach_end2

etc.....

Hey guys, I recently updated to UE4.26 and Houdini 18.5.532 and a pretty severe bug started to appear:

On reimport or sometimes recook of an HDA the static mesh input parameters (object_merges) are mixed up. Suddenly Input A has Input B's content in it and the other way around. There's no way to fix this except for deleting and recreating the asset.

The same is happening with curve inputs.

Is anyone else experiencing this?

Cheers,
choix

yeah trying to do simple stuff that used to work previously in V1 Houdini engine for Maya but now for v2 in Unreal. following some v1 tutorials on a simple poly reduce ,the desired 'Houdini inputs' never appear. the docs make zero sense to me. beforehand all you had to do was have a geo object connected to the in before you made the digital asset, now, no matter what I do I cannot get an input for unreal to appear in the digital asset once its unreal. All I want it drop stuff onto the input for houdini engine to cook. any simple tutorials on how to even get this elementary part working in V2? stuck after several tutorials and attempts so far...

eg following this real simple example. https://www.youtube.com/watch?v=v4pbcbqiO18 [www.youtube.com] the HDA when bought into Unreal 4.26 has zero inputs available... how do I do simple HDA's that allow me to use inputs..what am I missing?

**edit** to answer my own question... as usual if not following SideFX instructions TO THE LETTER it will not work. so I tried v1.. it WORKED exactly as intended, so I looked again at v2 explicitly and I realise I just copied houdini Engine v2 to the PLUGINS folder only... in the intrstructions it says put the folder into plugins/Runtime/ ... so doing this and now I have my Houdini Parameters and Houdini Inputs as intended. sorry for the age old USER ERROR noise.. carry on!

Has anyone been able to use the V2 plugin to create mesh sockets within UE4? I had a previously working tool (V1) that doesn’t work in V2. I tried recreating the tool in a more basic form specifically for V2, as a test case, and I can’t get it to create mesh sockets. The messages I see in the UE4 log mention a point cloud and “skipping”.

@monopole: The mesh sockets issue has been fixed in H18.5.569

@choix: The issue with inputs sometimes getting mixed up has been fixed in recent builds of the plugin, if not, please submit a bug with your HDA so we can try and repro it on our side.