Translations in Animation Reduced, Clippped, or Missing

I'm currently working on some really neat animations but I'm having one really rotten problem. When I upload the bvh files into SL, the translation is gone!

That is, I skate about on the ground and don't travel as far left, right, forward, or backwards as I should. It's as if the translations (horizontal linear displacements from the first frame) are either reduced, clipped, or missing (I can't tell which).

Now I have saved a bowling animation from Poser and it has a great deal of forward travel, so I know it's possible but for some reason it's getting lost in my animation. Does anyone have any ideas?

Prompt replies earn hugs.

~Ulrika~

Buhler?
...
Buhler?
...
...
Buhler?


Save Ulrika!

I figured it out. Apparently, it is simply due to differences in how Poser and SL represent the avatar. Things which looked perfect in Poser look a little less perfect in SL, giving the illusion that the animations weren't translating correctly.

So it's just the way it is.

~Ulrika~

Does this mean that you have to exaggerate translations?

Yes, sort of.

The problem I encountered is due to the fact that the default Poser figure and my SL avatar have different bone lengths.

When walking, the feet of an avatar with long legs will appear to move across the ground at a greater forward velocity than one with short legs. This is because the forward velocity of the body (hips) and rate of leg movement are recorded in the animation file. Depending on the height of the avatar with respect to the default Poser figure, the feet can appear to move too slowly, just right, or too quickly over the ground.

Imagine making an animation of a rolling wheel. If the wheel in SL were very small with respect to the one used in Poser to create the animation the small wheel would appear to skate over the ground, not spinning nearly fast enough for its forward movement.

Further, when kneeling, an avatar must translate downwards the height of its shin bone to give the illusion of being on the ground. An avatar with longer legs than a default Poser figure will appear to hover above the ground whereas an avatar with shorter legs than a default Poser figure will sink into the ground. This is because the downward translation of the body (hips) is set by the shin height of the default Poser figure and stored in the animation file and is thus most likely wrong for the SL avatar.

The only way to fix this is to use a Poser model whose bones exactly match your SL avatar or to compensate by exagerating or reducing translations and rotation rates.

This also means that, due to the customizability of SL avatars, it is impossible to make static animations that are perfect for everyone. One would have to have the ability to create a dynamic animation which changes rates as a function of bone sizes to get it perfect.

~Ulrika~

This is exactly the problem I've been noticing and getting frustrated over for a while now. I've been working on making an old-school break dance scene to some early 80's rap as well as translating Shorin Ryu katas into animations with little success (and missing the contest deadline! Ugh!).

Let's keep petitioning for the models LL uses to develop their animations as they seem to work universally. Maybe they have a python script that processes the .bvh's to translate to a conforming system used by the SL engine?

Actually, LL Poser models will not solve the problem!

The reason is that Poser figures and SL avatars are suspended in air by their hips. The height at which they are suspended above the ground in SL is set to be the height of the legs, to give the illusion that the avatar is standing.

Because the hips are the suspension point and this point is arbitrarily determined by the avatar height, it is impossible to get the feet to align with the ground unless the Poser figure exactly matches the SL avatar. Even if we have a LL Poser figure, if we modify the height of our avatar from their Poser figure, we'll have the same problem.

~Ulrika~

Ulrika - your a genius

At least I can customize for my avie (even if it will be a little different for others).

Thanks,
T

Thanks!

If you get it perfected let me know how tall your avatar is and how much you had to modify the offset in Poser. I'm working on a conversiont script.

~Ulrika~

I have finished an online tutorial which explains the phenomenon of floating, sinking, and skating avatar feet in Second Life animations. It provides illustrated expamples and recommends solutions.

The web page can be accessed here:

http://www.ulrikasheim.org/animation/translation.html

~Ulrika~

I'd like to ask a question, if I may, regarding Poser > SL anims.

Is it possible to get the feet and legs of an Av level with the hips (i.e parallel to the the ground to simulate driving with legs outstretched) ?

I've created an anim in Poser to achieve this...but when I actually upload and use the anim in a vehicle, the lower half (hips down) reverts to a knee height sitting posture.
The model used is the Hi Casual Man P2.

Any advice would be gratefully recieved.

Thank you

yes it is possible, u can IM me in game and i will help u if u like

When are you usually on ?

I'm on quite regularly but I've not seen you online so far. I'm running on GMT so I might be outta synch with you.

I'm getting desparate now, as I have 2 vehicles built now which look like they're Flintstone propulsion.