Hello Houdini Heroes!

Can someone explain what i'm missing - when I export my Rig and anims from Houdini Indie (13.0.515) to Unity (4.6) - the capture deformations don't seem to come along.

the animation imports into Unity, however it looks as tho the mesh is simply parented to the COM - with no deformations.

I've tried every flavour of .fbx in the export tool in Houdini but all with the same results.

Any help would be much appreciated - i'm on a deadline to get some characters into Unity and this is a real showstopping issue.

Many thanks for any help - I spent all last night importing / exporting and had the same results every time - very frustrating.

Rick.

Noticed your Mesh Plane is over Unity's import limit at 90000 polygons. Here's the error message it produced. Hope this is helpful.

Meshes may not have more than 65534 vertices or triangles at the moment. Mesh ‘pPlane1’ will be split into 3 parts: ‘pPlane1_MeshPart0’, ‘pPlane1_MeshPart1’, ‘pPlane1_MeshPart2’.

Noticed your Mesh Plane is over Unity's import limit at 90000 polygons. Here's the error message it produced. Hope this is helpful.

Meshes may not have more than 65534 vertices or triangles at the moment. Mesh ‘pPlane1’ will be split into 3 parts: ‘pPlane1_MeshPart0’, ‘pPlane1_MeshPart1’, ‘pPlane1_MeshPart2’.

Hi kwiknip - that is very very interesting…

I'm obviously doing something very wrong as my character is <3k tris!

Thank you so much for responding - I hadn't noticed any such errors, i'll go and do some investigating.

Rick.

Benchboy

Noticed your Mesh Plane is over Unity's import limit at 90000 polygons. Here's the error message it produced. Hope this is helpful.

Meshes may not have more than 65534 vertices or triangles at the moment. Mesh ‘pPlane1’ will be split into 3 parts: ‘pPlane1_MeshPart0’, ‘pPlane1_MeshPart1’, ‘pPlane1_MeshPart2’.

Hi kwiknip - that is very very interesting…

I'm obviously doing something very wrong as my character is <3k tris!

Thank you so much for responding - I hadn't noticed any such errors, i'll go and do some investigating.

Rick.

Hi

I tried also to export an animation (quadruped rig + skin) in all the FBX options to Unity without success. I submitted my file to the support of SideFX and the answer was: “it should work..”
If you have found a solution please tell me how it was done.
Thank you.

Benchboy

Noticed your Mesh Plane is over Unity's import limit at 90000 polygons. Here's the error message it produced. Hope this is helpful.

Meshes may not have more than 65534 vertices or triangles at the moment. Mesh ‘pPlane1’ will be split into 3 parts: ‘pPlane1_MeshPart0’, ‘pPlane1_MeshPart1’, ‘pPlane1_MeshPart2’.

Hi kwiknip - that is very very interesting…

I'm obviously doing something very wrong as my character is <3k tris!

Thank you so much for responding - I hadn't noticed any such errors, i'll go and do some investigating.

Rick.

Hi

I tried also to export an animation (quadruped rig + skin) in all the FBX options to Unity without success. I submitted my file to the support of SideFX and the answer was: “it should work..”
If you have found a solution please tell me how it was done.
Thank you.

Noticed your Mesh Plane is over Unity's import limit at 90000 polygons. Here's the error message it produced. Hope this is helpful.

Meshes may not have more than 65534 vertices or triangles at the moment. Mesh ‘pPlane1’ will be split into 3 parts: ‘pPlane1_MeshPart0’, ‘pPlane1_MeshPart1’, ‘pPlane1_MeshPart2’.

Having stripped everything back to the absolute minimum, Unity is only seeing <3k tris and 0 skinned meshes from the exported Houdini .fbx.

Hopefully a Dev will notice the attached .hiplc and comment.

I'm a fanatical Houdini evangelist and up until this my Houdini > Unity workflow was flawless - but this .fbx export/import problem has pretty much shut-down my project.

I did a simple skinned tube with an IK ‘leg’ set-up and this imported fine - so now i'm completely at a loss as to what is happening. My next step is to delete the character rig and start again from scratch…

If someone, anyone, pleeeeeease take a look and tell me i've been doing something ridiculously stupid i'll be eternally grateful and give you a %age share of all revenue from my free game I'm a hobbyist dev and consider every step a learning process, if someone can enlighten me it'd be much appreciated.

Rick.

We're taking a look at this. Stay tuned.

Hi Rick,

Do me a favor: re-upload your example file with /obj/officeDudeA/file3 locked with the geometry in it. I can't debug your setup with no model.

Also, how are you baking out the FBX? From a FBX ROP or from the File menu?

cheers,
-John

Thank you stjohn,

If i understood correctly - i've locked the file nodes and re-saved. Hope this is what you meant. Apologies some of the terminology of Houdini is still a bit alien to me.

Throughout my export adventures, i've been using the File > Export > Filmbox FBX dialog (all different types and varieties.

Thanks you so much for taking the time to look at this - much appreciated.

Rick.

Thanks Rick, taking a look now.

And yes, that's exactly what I meant. In Houdini when you lock a node, it freezes the information contained within it. That means nothing above processes or gets passed through, and it sends downstream the data it contained when locked.

This is useful when you have a huge amount of processing upstream that you don't need to cook every time and the downstream data relies on the node you've locked.

In this case, I need the file SOP to send geometry downstream, and since I don't have your original .obj file to read, I need the file SOP to be locked with the file already read.

Also, if you go to the /out network of your Houdini UI, you can drop down a render node specifically for writing out FBX geometry, and you have all the same controls as the File->Export stuff. MOre, actually. And you can save different render nodes with different settings. /out (or any ROP net) is where we put node for writing just about everything to disk: Geometry, sim data, images from 3d renders, and images from compositing networks.


cheers!

I'm going to kick this up to support.

What I can tell right now is that Houdini seems to be exporting the model and a cache file, which lets you play back your deformed mesh in Maya (just tried it, it works), but Unity can't make use of deforming geometry. This is why MegaFiers makes money.

It does seem to be exporting the rig, it's just not connecting it to the model, and none of the bones are visible in the character previewer.

I'll escalate this appropriately.

Thanks stjohn,

It's an odd one - I can import into 3DSMax fine, and weirdly import the .fbx back into Houdini fine; hopefully you and the team will be able to shed some light onto it.

Many thanks.

Rick.

I've gotten this issue in front of Jeff Wagner, and he'll give you the details, but it appears that Unity (like MotionBuilder) uses a joint-based connection paradigm instead of a bone-based one. Houdini is more efficient in that it uses bones for both transforms and captures, but the fbx rig generated from that doesn't provide all the information that Unity needs.

So you will need to modify your rig considerably, and Jeff will explain exactly how, but this document explains what is probably the cause of your issue:
http://www.sidefx.com/docs/houdini13.0/character/bonesvsjoints [sidefx.com]

cheers,
-John

Thanks John,

Very interesting - I look forward to Jeff's insight.

I really want to keep my game dev workflow in Houdini as I've been completely re-programmed into the procedural nature of H13. In fact, out of desperation i tried to rebuild a simple rig in Max (where I spent a lot of time learning rigging in the past) and found it to be incredibly cumbersome and frustrating.

Houdini Indie / Engine & Unity is such a powerful combination it'd be a shame if Houdini's awesome rigging / skinning / anim tools weren't available to a hobbyist developers pipeline.

Once again, many thanks for taking up this query and all the help provided.

Rick.

Hi John,

Bit of a shameless bump for this thread i'm afraid - i've moved my rigging and animating into CAT Studio in 3dsMax which isn't ideal - i'd much rather keep my dev pipeline to Houdini Indie > Unity.

You mentioned Jeff was willing to contribute some ideas - i'd be thrilled if Jeff could contribute - His Old School blogs were one of the things that got me hooked on Houdini years ago.

Any help would be much appreciated - i still haven't given up on rigging / animating in Houdini Indie just yet.

Rick.

Hi Rick,

Sorry, I've been out on holiday for a bit.

As far as I can tell, you will have to make your rig joint-based instead of bone-based, because FBX doesn't know what to make of Houdini's rigs. I'll pick this up again and see what I can come up with.

cheers,
-John

Hello, I'm not meaning to hijack this thread or anything but my other thread had no activity and this is somewhat related. I'm having issues with exporting blendshapes into unity and/or UE4 as morph targets. I also would like to keep my workflow to indie->game engine instead of needing max, so any help in this is appreciated. Since you're looking into the export fbx issues maybe you could also look into that? thanks.

https://www.sidefx.com/index.php?option=com_forum&Itemid=172&page=viewtopic&t=35645 [sidefx.com]

Same houdini FBX blend shape export to unity problem here - would be great to get a idea of how its done.

Thank you kindly

Hey Stjohn,

Many thanks for your continued input - i'll take a look at the practicalities of putting together a joint-based system - hopefully i'll be able to Digital Asset something together for future use - I still have faith in Houdini!

No worries about the thread-jacking guys - I am looking to fully integrate Houdini into my game-dev pipeline and these Unity (and UE4 it seems) issues are forcing me back into Max - Max seems so clunky and illogical now after a couple of years in Houdini.

Feel free to share any findings here

Rick.

Sorry I've gone dark. We're really slammed prepping for GDC.

But to clarify, at this moment, there's no quick fix for this. You'll have to re-rig with a joint-based system (you might be able to use all your existing bones and controls).

For right now, (and I apologize for the horror of this workaround), I think you should build a joint-based rig that references your original rig and its animations. You can do this with CHOPs or reference copies of the animated nodes or channel expressions, or copying and pasting channels, plus all the capture weights on a copy of the skin. Put this in its own subnet and export the subnet to FBX.


Re: Blendshapes… I can export the Houdini rig to FBX for Maya and Maya picks it up just fine. If I export to FBX from Maya and read it into Unity I get nothing. But then again, I suck at Maya.