CMU, make walk, MH8 vs MH7

[mlbspike]

Was pleasantly surprised how well the sample motions I tried worked, with 7. 8 has distinct pluses, but now the 3 sample motions all have the arms severely penetrating the legs. One of the advantages of 8 is that the rig is mecanim friendly, when imported into unity. Not sure if there is a relatively simple solution, or if I need to use 7, and legacy mode, in Unity, and check back later. I'd be happy to experiment with things further, if I had a better idea of a profitable direction to take, but ... I'm also impatient to return to my game coding in unity, and the time expended trying different things is becoming frustrating, with little to show for it. Seeing an 8 model with textures in unity looking so impressive is making it pretty hard to let go, without further efforts, and I'm hoping someone can steer me the right direction. If my only choice is to use rotations to hand tweak the motions, that's pretty discouraging, and would seem odd, given how well thing worked with 7 (non inter penetration wise). Thanks for any help, and of course thanks to the developers for the impressive piece of software.
Michael

[ThomasL]

The tools in the Edit Actions panel allow you to edit the motions afterwards, see http://makehuman.org/doc/node/blendertools_makewalk_user_interface.html . In particular, it may be possible to fix the penetrating arms by rotating the clavicle, deltoid and upper arm bones into position at some frame, and then press the Shift Animation button in the Global Edit section, with the bones above selected. As the button name indicates, this shifts the bone rotations correspondingly for all frames.

Perhaps one could also fix this by changing the T-pose file for the MHX rig. MakeWalk calibrate the animation transfer by posing both the source and target armatures in T-pose at frame 0. A different T-pose would thus change the transfer. There should be something written about how to do that.

[duststorm]

Perhaps one could also fix this by changing the T-pose file for the MHX rig. MakeWalk calibrate the animation transfer by posing both the source and target armatures in T-pose at frame 0. A different T-pose would thus change the transfer. There should be something written about how to do that.

Is it safe to assume that BVH files are in a proper T pose at their first frame? I have seen a lot of it that doesn't.
Perhaps there could be some kind of interactive way to configure the reference pose in the MakeWalk tool. This could be useful for debugging and fixing such problems.

Indeed this is something worth documenting.

[mlbspike]

Will experiment with the tpose idea. In this case the tpose's in the cmu motions looked good and worked nicely with the mh7 model. Maybe I can compare the mh7, and mh8 tpose's.

[ThomasL]

The animation from the bvh file starts at frame 1. MakeWalk appends an extra frame 0 where both the source and target armatures are in T-pose, see http://makehuman.org/doc/node/blendertools_makewalk_basic_workflow.html . The T-pose is generated automatically from the rest pose by posing the arms along global X and the legs along global Z.

[ThomasL]

I looked into this a little further, and it seems that the code for changing T-pose is flawed. It will be fixed in the next few days, but currently it is not possible to change the T-pose for the mhx rig, or any other rig exported from MH for that matter (the T-pose is defined in the same way for all MH rigs, since the mesh is identical).

In the meanwhile, I suggest that you try to shift the animation as I described above. Or you could try to just translate the f-curves in the graph editor. For Euler angles this should be equivalent, but quaternions will no longer be normalized after an f-curve translation. It is also possible to locally edit the animation after it has been loaded. I usually end up spending 75% of my time cleaning up the animation after it has been loaded.

[mlbspike]

Thanks. Still experimenting. What I have is usable, so I may progress with what I have till the update.

[ThomasL]

I rewrote the code that handles T-posing. The new versionof MakeWalk has version 0.943 and is in the default branch of HG. I can package it as a separate downloadable zip file if you don't know how to access HG.

The T-pose buttons are located in the Target armature panel. They are:

MakeWalk T-pose:
For an armature exported from MakeHuman, use the predefined T-pose rather than finding T-pose automatically.

Set T-pose:
Pose the character in T-pose, either the default T-pose or a defined one.

Define T-pose:
Define the current pose as T-pose

Undefine T-pose:
Remove user-defined T-pose, using the default one in the future.

Load T-pose:
Load T-pose from file.

Save T-pose:
Save the current pose in a T-pose file.

The next two pictures show the same frames (0 and 37) from a CMU bvh file, with the default MakeHuman T-pose and a user-defined T-pose, respectively. The user-defined one looks strange as a T-pose, but yields better results for arms-down poses. However, using the T-pose is not a panacea, because retargeting of poses close to T will probably be worse. But then again, your character will probably seldom be close to T-pose unless you animate something like a crucificaction scene.

[mlbspike]

Thanks! Will try it out as soon as possible.

[ThomasL]

In the latest version I moved the T-pose buttons back to the Utilities panel, Posing section. Although they are primarily intended for dealing with the target armature T-pose, some of them make sense for arbitrary poses and for the source armature as well.