Transforming Vertex Animation to Joint Animation

[elmlish]

Hey There...
I'm currently stuck on crafting this mel script to compensate for the weak exporter I'm forced to use.

I created some animations using the Blend Shape stuff but found out too late that that particular deformer wasn't supported by the exporter. To get around this I thought I would Bake the animation into the poly mesh. It turns out that Vertex animation isn't supported either.
I've cooked up the following script that gets me a joint at the location of each vertex in a duplicate of the animated, shape blended model. I'm currently skinning the model by hand but would love to figure out a way to do it via this script.

The main thing I really need to figure out how to do is to take the vertecise from the shape blended model and have them drive the animation of the Joints on the duplicate model. (does that make any sense?).

I've found that I can't bind a Joint or nearly anything else to a vertex and so I really don't know what I can do here. If any of you kind people with loads of freetime and a breathtaking knowledge of the wonders of Mel could help out this relative newcomer, I'm sure he would be most grateful and would mention all benefactors in his yearly letter to Santa.

proc string[] jointsToVerts()
{
string $sel[] = ls -sl;
float $selPos[3] = xform -ws -q -t $sel;
PolySelectConvert 3;
string $verts[] = ls -sl -fl;
select -clear;
string $jParent = joint -name "jParent" -p $selPos[0] $selPos[1] $selPos[2];

for ($v in $verts)
{
float $pos[3] = xform -ws -q -t $v;
select $jParent;
joint -p $pos[0] $pos[1] $pos[2];

}

skinCluster $jParent $sel;

return $sel;
};

Thanks for any help you can offer.

~Israel~

[jeffd]

Wow, this is really a far-out idea. I couldn't imagine this actually working in the end, but good luck.

A couple ideas come to mind as ways around binding to a vert. First, I'm not sure off-hand, but is it possiblt to bind to a cluster? If so, just make a cluster at your bind vert. The second thought would be to use the pointPosition command to just grab that vert's position every frame and us that to drive the position of an object or the joint itself.

--JeffD

[elmlish]

I was thinking along the lines you suggested at just about the same time you had suggested it and came up with this solution. Now it's not complete but it serves my purpose and I need to get stuff done now..

Some notes:
-- This is not my first mel script, but it's probably pretty close so don't expect proper form or procedure but I think it works.
-- I take the Original Blend Shape driven poly mesh and duplicate it.
-- Then I reselect the Blend Shape Mesh call this script and watch as Joints are placed at each vertex of the mesh and then animated along the path our Blend Shape animation takes us.
-- After that I reset the time slider to the frame at which I duplicated the Blend Shape Mesh.
-- And then select the individual joints, not the heirarchy, and the Duped Mesh. and Skin that sucker.
-- I Had to Skin to Selected Joints to Closest Joint with Max Influences set to 1 with a very small dropoff.
-- then voila! I had copied the Blend shape animation to a new Bone driven setup.
==
Now the problem with this is that there end up being a large number of bones created which can be hard to handle later on.

///////// and here it goes...

proc string[] blendToBone()
{
string $sel[] = ls -sl;
float $selPos[3] = xform -ws -q -t $sel;
PolySelectConvert 3;
string $verts[] = ls -sl -fl;
select -clear;
string $jParent = joint -name "jParent" -p $selPos[0] $selPos[1] $selPos[2];

for ($v in $verts)
{
float $pos[3] = xform -ws -q -t $v;
select $jParent;
joint -p $pos[0] $pos[1] $pos[2];
}

float $rMin = playbackOptions -q -min;
float $rMax = playbackOptions -q -max;
int $frame;

for ($frame = $rMin; $frame <= $rMax; $frame++)
{
int $vjCounter = 0;
currentTime -e $frame;
for ($v in $verts)
{
// --get it's position..
float $vpos[3] = `xform -q -ws -t $v`;
// --get the name of the appropriate joint incremented by 1.
string $jName = "|jParent|joint" + ++$vjCounter;
// --set the pos of the joint to the pos of the vertex..
move $vpos[0] $vpos[1] $vpos[2] $jName;
// --set keyframe
setKeyframe -at translate -t $frame $jName;
}
}
return $sel;
}

[jeffd]

Did you say a bone for every vertex?

If this is for game export, your programmers are going to kill you!

--JeffD

[elmlish]

yes.. a bone for every vertex...
I know.. I know..
I swear I won't do it again. well, maybe.
I'm hoping to get them to accept mesh deformation animations. Maybe if I made a 1k poly character and then do this to it the programmers would go kablooee!