Limb ratios in SL

I was playing around with Daz Studio, importing the Poser models and skeletons for the SL avatars.
While it seems to work nicely, I was wondering:
What do people use as the average/typical size for various limbs? The ratio of, say, arm length to torso can have quite a big influence on the animation.
I realize that this varies wildly from avatar to avatar, but the experienced animators out there must have some "golden numbers" they use to make their animations look good on a reasonable amount of avatars. Anybody care to share those?

Not really - if an animation is for a particular avatar then the required size and shape can be modelled. Some animators will do versions for short and tall avatars, where this is significant - e.g., for child avatars.

If you check out Bits & Bobs website you can find the "standard" sizes they work with.

There is no easy answer because one size just doesn't fit all. The best advice I can give to other animators is not to animate motion which is size critical for SL work - bit of a limitation, unfortunately.

The average, set all your sliders to the tallest, longest, most broad shouldered and thin waisted you can numerically get away with. We are all surrounded by 8 foot uber skinnies, I am anyway. usually get a neck cramp mid day from looking up so much.

But seriously, I usually test at about 80% when I make animated items. But I always slide up to 100% just to see how the 'average' height will look on such an item.

sl animations are void of inverse kinematics but have very variing ratios, also a lot of data can not be read from a script, therefore it is never very accurate.
performance goes over accuracy here.

in poser using Supermodel and Hero figure heights fit the majority of your average users since most folks use very tall and full figured avatars... harder to gauge with some though, like child avs, furries or those who decide they don't want to be 7 feet tall, lol. That's one of the reasons that I don't do too many "unisex" animations anymore... I do separate male and female animations, even on ones that should be unisex... and even then they don't always fit quite right... this has been an issue that some of us have been griping at the lindens about for years... that and the bloody 30 second animation limit... and sometimes the fact that the loop upload control is percentage based.

Animations for men are easier: most male shapes are pretty much as described above.

For women, it's all over the map. Some women have very long arms and legs. Others just stretch their legs. Some are petite, others are nearly as tall as the men (and with heels on, taller). Some women have very very short torsos, others have long ones -- and there's no correlation to arm length.

It's a nightmare!

I tend to animate females to work with the built-in "sexy female" shape, and I find that while women vary quite a lot, it seems to be near the middle in a number of ways. That's an unscientific observation though, and I wouldn't be too surprised to find I'm a bit off the mark.

I chose that shape before they added all the new newbie avatars, which I haven't checked out at all.

One of these days I'd like to make a modified client that accumulates average shape dimensions for ever av I click on, and cruise the world making a sample to find out the average. Why wait for my click? Because I don't want to mix male and female shape data. But I doubt I'll ever get serious enough to make that client modification.

Yeah, it's annoying that the loop is percentage based. Is there a JIRA entry for that?

It's so silly. The first thing the client does is turn that percentage into a frame number. Also, by default, it's wrong: it ends up pointing to the T frame, which gets skipped, but this causes a hesitation in the animation loop. It's not noticeable on any animation where the first frame after the T frame is the end of a motion. When it's in the middle of a smooth motion, the pause is a bit jarring.

Yeah, it's the arm length vs torso/shoulder which really gets me. (The ridiculously high heels are pretty much a given).

I'd *love* to see that data. I've been thinking about putting together one of those dreaded surveys to collect it, but a more-or-less automated scan would be awesome.

I think it'd be hard getting a lot of random people to provide all the necessary information. You'd need at least av height, torso length, and arm length, shoulder width, and perhaps others. And you'd need to know which numbers have a scaling effect on others. For example av height scales arm and leg length, I believe, and there may be more of thes.

That's why I'd rather simply collect the resulting av dimensions, and convert as necessary to get the corresponding dimensions for a BVH file header. But I suspect I'd get into trouble trying to understand this area of the code.

And I've learned that I can't expect much help from the community of animators. The few requests I've made for help for the good of us all has fallen on deaf ears. For example, I offered to revise the optimization code that gets run on animation upload, but I needed example BVH files to test, and got zero offers. Sure, lots of people would like to see the optimization improved (making our animations look more in SL as they do in Poser), but not enough to contribute anything. I modified it to work fine for my animations, but in a way that isn't general enough to be a solution for the whole the community of animators.

Not to say the community isn't helpful at all. When it comes to questions about using the animation programs or details on how things work inworld, folks here are great.

I'm guilty of not checking the forums nearly often enough... when I do, I make replies, but I had never noticed your request, sorry about that... if you want assistance, let me know and I'll see what I can do... I can't tell you how many animations I've trashed because you just couldn't get the motions in SL like Poser without horrible distortions.

I also think by this point when an animation is applied to an AV, the bone lengths and joints should be applied dynamically, based on the size of the AV running the animation... I wouldn't think it would take that much work, but I haven't read that portion of the code either, so who knows.

Thanks Chavo; perhaps I should try a bit harder on that thread and bump it a few times. But there are relatively few posts on this forum, so it sat on the first page for a good while.

BVH files are a set of angles (rotations) to apply to each axis of each joint, in a time series. The header contains a stick-figure model of the joint system, including distance between joints, but that information is ignored by SL because it uses the avatar's body settings.

It's not possible to automatically compensate an animation created for one av shape to fit a different av shape, without being able to specify what aspects of an animation are important. In other words, if we made the arbitrary choice that the relative resulting location and orientation of the hand with respect to the head was the important thing in the animation, it would be possible to compensate (though probably not *easy*). And that would be correct for an animation where the person was wiping their nose. But for an animation where the person is rubbing their belly, it would be wrong. Matters only get worse for couples animations, where the important thing is often where some joint or endpoint ends up relative to a part of the partner's body.

In the future, we'll have rubberized animations and the abililty to make a joint or endpoint "magnetic", attracting it to a particular body part (of that av or another av's). But don't hold your breath; I seriously doubt it will happen any time soon in SL. We're still a long way away; along with that we'd also want physically modeled avs for animations, where an animation won't allow things like intersecting bodies (e.g., an arm going through a leg).

Yeah, it would be a total pain in the @$$... but if we had to use one given character in Poser (insert your animation environment here) and use only that one, it should be possible to apply the same basic logic that is used to change and avatar's shape from the default to this new animation and get the same basic size changes....

You're right though, there would still be a lot of areas where there would be bugs... especially in the cases of interactive animations that involve 2 or more avatars... as even adjusting based on height, something as simple as a kiss isn't going to necessarily work well between a 5' 3" AV and a 7' AV, no matter how well it is adjusted.... hence things like hug-o-tron that try to overcome this by connecting AVs at the hips to remove more of the height difference...

The rubberized idea would be cool though... taking it along the idea of "magnetics" and being able to say "right hand should be at lower back center" in one frame, then "right hand should slide along the plan of the back to just below shoulders", repeat as needed, etc..

I wouldn't want the nightmare of having to try and code that though, especially in both DirectX and OpenGL, lol.

I have been animating in SL for two years an have specialized in animatin pairs of avatars (Rendezvous coupls animator)

here are my two cents

1) i mke the female of the pair 10% smaller in my layout - this seems to translate pretty well inti SL reality

2) As far as i cn tell, the SL importer completely ignores bone size and only imports bone angles. this makes it impossible to adjust for the ape index or the super avatars or make it possble for any random av to properly grab the steering wheel of a boat, for example or arms to properly wrap around the other avatar,s waist.

3) if you are making animations to be put into other uncontrolled products, you will not be able to control what happens at the oter end, but, if you are creating a product using animtions where you control the product, then there is a lot you can do to make the aimations work very well.

example: In my products, I use the llSetLinkedPimitiveParams to automatically adjust avatars for certain positions so that kisses match, hand holds, etc. match. I use the avatar size for each and then work out fomulas that handle most of the issues. it takes lots of math and is very tedious, and I am not going to share all these hard earned IP secrets here, that is for you to figure out for your product.

You also need to come up with a simple way to allow users to adjust the position of the avatar in 3d- when two avatars kiss, if the lips meet, most users will not complain if their feet seem to be buried in the floor of if they are floating a bit. but the lips are important, or the hands or whatever.

you also need to think though your animations and design them with all of what is going on so that users 'perceve' an experience, even when the RL action would probably not really be like that. good product design is all about illusion and not reality and this is particularlt true in SL.

I also created an intermediate program in VB6 where I can adjust the hip location of a given .BVH fle just before import. so if I create a very complex couples interaction and on first import,the female is kissing his kidney, I can move it without having to go back into the program for generating the animation. It also tells me up front the relationship between frame 1 and frame 2. its a hack job, or I would offer to give it out.

for other usefull hints, check out an earlier post of mine called "animations unraveled and explained" my earlier treatice on animation for SL.

hope this is helpful

Have a good idea.... I'm very new to all this but here, I think is a very good suggestion, well here goes!!....

When you have animations which work well on testing, be it a single pole dancer or couple dancing/interacting etc, why not provide an "Info" button which gives a Note Card detailing the actual slider values for the avatars used in production??

It's common sense really,....but I'd bet most people wouldn't mind adjusting limbs and saving an idealized "shape" for using a particular bed, or pole, chair etc!

We would love to know exactly what Male/Female slider values to set for near perfect animation matching for various products, so why not give it freely to us customers??..

It's a good suggestion Robbey and I should like to do this, but I do not know how to equate the Poser figure size to the slider values for Appearance in SL. Maybe if someone has worked out a table to convert the two, they could post about it here.

Some animators do give details of the avatar size(s) that they used for testing - e.g., Bits and Bobs use a fixed male and female avatar size - see their web site.