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Netvudu
04-04-2013, 08:47 AM
Hi, before I fogbugz it, did anybody notice a scene with bones (joints in my case) deforming properly until you reopen the scene and suddenly getting all deformations wrong? Whatīs worse, trying to rerest bones position on the first frame doesnīt improve anything.
Thankfully I had an mdd saved that proves that prior to closing and reopening it, everything was fine.

RebelHill
04-04-2013, 09:06 AM
This is jsut a resting/binding issue that doesnt rear its head until a scene is reloaded... the same thing has always been able to happen. Re-resting at start frame will fix it but ONLY if your bones are in base (bind) pose on that frame.

Netvudu
04-04-2013, 09:15 AM
Hi Craig. Thanks for the help. What do you mean by "only if your bones are in base pose"...it was a mocap skeleton so I fixed a bit the bones position to better fit the character..is this the wrong workflow to avoid this issue?
I ask because I now try to rerest on frame 0 but it doesnīt change anything...it still shows the wrong deformation. Should I save a duplicate "rest pose" for the bones before adapting bones just in case this happens?

Is there any fix I could apply now (apart from going back to previous incremental)?

mav3rick
04-04-2013, 09:43 AM
it means if you have base (setup position) of bones you can than rest them and animation should be OK after... otherwise you could end up with deforming mess ... happened to me few times but have learned it in the end.... try create all keyframes at some negative frame... deactive MOCAP put all your bones in 0 0 0 rotation and rest them..

while we are at resting... question to Rebel... is there some plugin that will internally save rest position/rotation for character once it is done setup before animation so that whatever reason happen we could create base bind keyframes at desire frame and fix rig ?

RebelHill
04-04-2013, 10:01 AM
Ahh... that TOTALLY explains why it went bad...

Base pose refers to the bones posed into the mesh as the mesh would appear in modeler (or with "enable deforms" turned off)... the MESH base pose. Often mocap with an included mesh will be missing this pose, and its a right pain to try and set it manually... its basically an eyeball job. If however, youve got a mocap skeleton and you're trying to fit it to some other mesh... yeah, just nudging the bones around like that is a REALLY bad idea most of the time, and unless the adjutments are small, you'll often end up with messes like uve encountered.

For the most reliable pipeline... you'll want to bone up your own character (using a mocap "style" bone set) and use an animation retargeter to transfer some other skeletons motions onto your own characters proportions... Obv, LW lacks such a tool, and this is what people commonly use stuff like MB for... However, there are other options... such as animeeple if u have, or can track down a copy, or more recently Ikinema's web animate, which into the bargain gives you all manner of animation editing tools and is really, really cool. Be sure to check my mocap guides for all the pertinent details... http://rebelhill.net/html/lwandfbx.html No Ikinema coverage, but as u can see from the MB, animeep, and iPi examples... the out/in/out processes is exactly the same in all instances.

As for a plugin to store and replace base poses... not really... You could use IKB, which has pose store and recall... you could be sure to always use 0'd bones at base pose, making getting back to it as simple as selecting all and hitting 0,0,0... or such a plugin would be easy enough, I guess, to make with LS.

However the most ideal way, which gets around all such problems, is to ALWAYS keep base pose frame at 0, or whatever in every animated scene, clearing it (if even necessary) only when you've done and finished the animation completely.

Netvudu
04-04-2013, 11:55 AM
I understand.
I have already done retargeting several times using Motion Builder. We got an ipi license and kinects around. Itīs a simple process but if you donīt care much about skinning for background characters applying the mocap directly is what I tend to do as it tends to be the fastest thing.

Actually I found out that what REALLY happened is that somehow the hip got rotated 180 degrees on the rest pose. I was fiddling with it to fix some flipping (yup, I already tried applying your handy RH Euler Filter for ALL bones and it seemed to crash Layout so I couldnīt rely on that in this case. Usually it works fine) and apparently I accidentally rotated the hip 180 degrees on that rest frame, but I didnīt notice because I didnīt re-rest then.
Then when I reloaded the scene the mess appeared in all its deformed glory.

I already fixed it.
Anyway, itīs still good to know about these issues. Thanks for the tips.