Hi, is anyone using Houdini indie in their workflow for rigging and animation?
We are having a hard time with the FBX files exported from Houdini, not a single animation
does anything within Unity, but any of these animations would work OK in FBX viewer or ClockStone FBX viewer.
We have dedicated a week in analyzing the problem without good results or clear understanding on what we could be doing wrong. Some of the questions that could not be responded are: does Unity understands bone based animations? does it works only with joint-based animations?, Are SOPs converted to key animations?
Can someone please spare some details on their rigging/animations/export workflow in Houdini?
Attached is an example of these animations.
Yes - No - I don’t know what SOP’s are? That’s not a common animation term.
I imported your fbx into Max 2012 and the problem isn’t Unity, the problem is the skinning information on the character.
It looks like the only thing animated in the fbx is the hat bones.
OK I’m not sure what the problem is - I know there’s some things wrong with the fbx you provided and probably the process in houdini, so I’ll just point out things that are wrong with the fbx and if the problems are fix you may get better results in Unity.
The character mesh is parented to the root bone - player_fbx. Not good. The character mesh doesn’t need to be parented to anything once it is skinned properly.
There is not skin data on the mesh so therefore there won’t be any animation data on the character. The character needs to be skinned to the bones.
3.For some reason everything has a keyframe on it near frame 1. Not at frame one. Possibly this character was animated using ‘ticks’ instead of frames? I changed the fps in Max to 60 frames per second and the key jumped from near 1 to 2.5 so the keyframes on the hat bones used an uncommon keyframe calculation. The common animation fps for 3D game animations is usually 30 or 60 frames per second. Don’t use ticks, SMPTE, or mm:ss:ticks.
The only objects that need to have animation keys on them are the bones. There is no need to have keyframes on mesh objects.
There is a TON of bones in this character for such a simple character. I counted over 260 bones/helper objects for this character, not counting the weapon or the mesh. I’d say this character could be animated with 20-30 bones total.
This character is from the Unity survival shooter demo/tutorial which actually has 68 bones for the character (double the amount needed for this type of character). Why don’t you just use the character from that scene? It only has 3 animations, but it’s still - already in Unity and setup and working.
There are probably some houdini specific workflows you have to edit to get things to play nicely in Unity. Everybody has to edit there character pipeline depending upon what the final outcome will be. Skin is required for character driven by bones.
Hope this helped a little. I’d suggest searching some houdini specific animation forums, maybe cgtalk or polycount, and look up specific character animation processes for houdini to unity.
This may help also http://docs.unity3d.com/Manual/HOWTO-exportFBX.html
Thanks TheAnimator2b, you have certainly provided plenty of rich information that can be used to clean the model.
With this little model we tried to achieve some basic animation from Houdini to Unity, so only the hat was animated. I will pass down this information to our modeler, hopefully after clean up it will be understood by Unity. I post latter this week the result. Thanks again
Hey @BlindCatt - importing this into Max showed the results below.
There was only one static keyframe on all objects at frame zero so I couldn’t confirm there was any animation data on the rig.
There seems to be some skinning problems with the model. Did you see this when importing into Unity?
When exporting the only things that needs to be exported is the mesh and the bones. All other control objects that are part of the animation rig but don’t influence the skin do not need to be exported. So angle/joint targets, effectors, IK goals, manipulators, all those things are not needed when exported. Did you find any houdini to Unity specific workflows to follow?
A good process to test the export is to export like normal - as fbx, then reimport back into the authoring package (houdini). If the mesh and rig look/act incorrect when reimporting into houdini, it isn’t going to be correct in Unity.
This is a common workflow I perform (in 3D Max) before exporting directly into Unity just to confirm everything is working as it should be.
One other thing I noticed on some of the control objects (dummies) the scale value was negative 100. These objects may have been mirrored in houdini while setting up the animation rig - which results in a negative scale value. I suggest resetting all scale values of everything including mesh objects, and control objects to 100 or 1.0 before animating and especially before exporting or you could see some adverse effects from this down the production chain.
Having a negative scale value on objects would not result in the animation being stripped from the rig or the animation not showing up at all, but it will result in hierarchies not performing as expected when in Unity.
Can you provide a screen shot of the fbx export settings you used? Each authoring software has different looking export UI but I may be able to discern if something in the export settings need to be changed with a screenshot.
The rig looks a lot better. Much lighter and easier to handle.
Thanks for this post and sorry to hear you’re having issues getting the animation from Houdini into Unity. It’s definitely possible though so keep at it!
-Can you let me know what version of Houdini you’re using?
-Have you tried using Houdini Engine at all yet? It might be better to work with Houdini Digital Assets instead of FBX.
-For more visibility, would you mind posting your question into the Houdini forum here?
I’m going to try to get a tutorial made that shows how to correctly export animations from Houdini to Unity, I’ll be sure to post it here when it’s ready. Thanks for your patience.
(Thanks also to theANMATOR2b for his helpful replies and suggestions!)
We are using Houdini 14 Indie.
We have not tried to use Houdini Engine, as my understanding is that it requires a full new license on the developer machine plus the license for the engine. So that would require additional investment that at this point a would prefer to avoid, thus trying to get FBX to work correctly. We also posted this in the sideFX site
I have also contacted Digital Tutors for some assistance and they have been very professional and may be working on a related tutorial for this, but as for now it is just a possibility.
