Jumping on to this thread a year later than the last post, may I offer some
"helpful" info.

On BVH files ->  Marvelous!  They take the following format.

Hierachy -> Data.

Nice and simple.  Or not as the case may be!

The first set of data gives the "reader" the opportunity to sort out the lengths
and offsets of all the bones in a kind of natural pose.  This gives us POV
coders the problem that everything has to be absolute or useless/TMTC*.

The only way to take in a BVH bone Hierarchy is to import it via #read.  Problem
number two comes in there.  We can't read any file that doesn't separate
everything with handy commas (Maybe POV4 might? - Hint hint!!).  So, that's
that screwed then.  But even if it could, could we come up with a
POV-source-hierarchy that is able to adapt itself?  I couldn't, not without a
lot of time spent at the local mental health rehabilitation center.

So, the first half of the BVH format is not good for us.

However, I did have some (limited) success with the second part!  BVH part two
takes the the format of a spreadsheet.  I.E Row = Frame, Column = Data(Rotation
angle, etc)

In the Hierarchy, BVH tells us how may "columns" each bone will take in the
motion data.  So....

--= BVH data starts here =--

HIERARCHY
ROOT Hips
{
 OFFSET 0.00000 0.00000 0.00000
 CHANNELS 6 Xposition Yposition Zposition Zrotation Yrotation Xrotation
 JOINT LHipJoint
 {
  OFFSET 0 0 0
  CHANNELS 3 Zrotation Yrotation Xrotation
  JOINT LeftHip

->BVH hierarchy data continues from here!!

->Until here where it becomes...

MOTION
Frames: 432
Frame Time: .0083333
16.1514 23.2122 -8.4365 -5.3491 -3.5725 9.9077 0.0000 0.0000 0.0000
16.1501 23.2332 -8.3453 -5.1539 -3.7875 10.0314 0.0000 0.0000 0.0000
16.1690 23.2611 -8.2105 -5.1359 -4.9409 9.8798 0.0000 0.0000 0.0000

--=And then ends=--

In the hierarchy bit, you'll notice "CHANNELS 6"  followed a bit later with
"CHANNELS 3".  These two little nuggets of info describe the format of the
motion data detailed under "MOTION".  Then "Xposition" etc describe what order
all that data is in.
So,

"Hips.Xposition = 16.1514, Hips.Yposition = 23.2122, Hips.ZPos...
....Hips.LHipJoint.Xrotation = 0.000".

Nightmare!!

However it is possible, if you cut'n'paste the motion data into a spreadsheet,
organize it so that it fit's onto your rig and save it as a CSV file (then add
a comma at the end of every line), you can read it into POV to take care of all
your animation!

Way too long winded, innit.

To simplify matters, and this is what most professional animators do, it to use
History Independent Inverse Kinematics.  I.E, you position the main body mass,
set up the spine curve and where the hands'n'feet should be, then let maths do
the rest!

I should probably leave it there for today, but I might post some more "useful?"
information on this thread later...

*Too Much Too Code - Variable skeletons will take hundreds of thousands of line
of code!

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