Full Body Tracking problems | Voters

Full Body Tracking problems

complete

Digitrevx

Since friends and my self have ventured into full body tracking recently I've noticed issues with it's implementation.
--- The thigh should not be rotating 1:1 with the ankle. This has never been how the human body works. Most characters are not weight painted for such abusive twisting in the hip. 
--- The head vantage point of the avatar sinks into the neck or chest when sitting or laying down. This is pretty important and problematic since one of the entire gimmicks of full body is to be able to do this in VRchat. 
--- Calibrating every avatar when you change to is silly specially if it's an avatar you used in the same session. Allow for profiles or store the information with the avatar.
--- Proportion adjustment is necessary. It's obvious at this point forcing realistic proportions onto fantasy characters with limbs that are various size is a problem. Even for standard VR users. Arm length adjustment without effecting your player height is very important. This can potentially solve the head sinking into the chest when sitting or laying down. 
--- Avatar arm IK freaks out when laying on your back and reaching for the sky. 
--- Clavicle bones are not being included in arm IK. It is for standard VR users. Why is full body IK not including this bone? It makes avatars look silly.
--- Location of player height button and scaling the world as you change it with a "EXIT VRCHAT" button next to was probably not the best design choice. Perhaps informing desktop users this does nothing for them would be helpful too. >_O

January 29, 2018

Fax

marked this post as

complete

Thanks for the feedback!
Earlier this year we released the IK 2.0 update, bringing some big improvements VRChat's IK system.
https://hello.vrchat.com/blog/vrchat-ik-2
Please let us know if you have any other feedback related to VRChat's new IK system.

EctoSage

Kindly hire the person who made the IKtweaks mod, as they heavily improved what is in the base game. The main improvement, being the ability to actually lay down, & bend your back, without your head dislocating from your view.

They also add the wonderful benefit of being able to lay on your side, without your character spazzing out, and trying to keep the chest pointing upwards.

General Cap

Yeah even when using an Xbox one Kinect I had the issue of the head sinking into the body a bit when crouching or sitting. It made using any avatar with a mesh near the neck such as fur or a shirt collar unpleasant to use. There's also the issue with any model that has long legs where you can't reach the floor. With most models with long legs, the foot trackers usually wind up somewhere near the knee or between the ankle and knee, and the waist either winds up below the crotch or sometimes in the stomach. Only properly proportioned models have the feet trackers appear in the feet or at the ankles, and the waist tracker appear close to where it needs to be.
I imagine it'd be hard to make a workaround for nonstandard proportions, and the current calibration method seems like a trial and error system for getting your veiwport placed correctly on an avatar and your real world arm length to mostly function with the in game model. I think maybe one way to fix this issue is to try and use the current system for the upper body (head veiwpoint and hands) and use a displacement system for the lower body (waist and feet), although this probably would require references for the tracker placements on the avatar (which could just be a bone already on the model itself).
As things are, there might just need to be better developments for full body tracking to fix some of the issues in game, as there's really only two viable options at the time of this post - using a kinect or the vive trackers.

Horai

This, I don't want my head sinking into the chest anymore

Stormchaserguy

Ankle rotation moving the thigh 1:1 like he said. It makes weight painting miserable for the thigh area.

VRArt1

What I think they should do is a two armature system to avoid the proportions bit and the recalibrating bit. With having a control armature that matches your real world proportions and then the armature of your actual avatar copying that over. That way you can just calibrate once at the start and then easily switch between any of your other avatars without having to calibrate again until your next playthrough.

I'm not 100% sure how well storing the calibration would be though since it could be easy for there to be shifts on how you're holding the control or where exactly your trackers are placed between play sessions.

Lamb_

There's a few more points I've seen in other canny posts regarding FBT that would be great if implemented.
First of all, when tracking is lost, keep the position of said controller/tracker where the tracking last sees it. This would fix the problem where someone's hips/legs goes flying off into the distance when tracking is lost.
It would also be great if we can get a recalibrate option in the menu for FBT as well. Having to switch to and fro between avatars just to recalibrate FBT is a hassle.
Regarding the issue of pov sinking into the torso when sitting, it seems like the arms and hips have higher priority in terms of tracking when in FBT. The head has tracking priority when out of FBT mode, there's no reason why that shouldn't be the case in FBT as well. Nothing brings you out of the immersion quite like having your head sink into your neck when sitting down.

Hugo Zink

yeah that's probably right. When my hips fly off, they also fly off in SteamVR. Not much the game can do to prevent that.

The head sinking is by far the most pressing issue. The cause appears to be that the fullbody IK component requires a "head effector" component, which doesn't guarantee that the head will meet the target. Switching to VR IK would be for the best.

HostileLogOut

funny how you mention it. but you just need a proper avatar made for full body. non of these issues happens with any of the people i know using full body. if your viewpoint is wrong with FBT then your avatar is not made for FBT. if your head follows your arms if strechted. your avatar does not support FBT. and i can go on forever. majority of avatars are not correctly setup for FBT due to the fact that only a limited amount of people uses FBT.

Hugo Zink

HostileLogOut: this is wrong.
First of all, you shouldn't have to mangle your avatar to get it working in FBT. You're implying that the default Nikei and Y-Bot are not made for full body, in which case it seems like a very hard bar to clear.
The viewpoint detachment is simply due to how the IK is set up, with Full Body Biped IK and a Head Effector. The viewpoint doesn't 100% dictate where the head bone goes, so if you get further away from the idle pose it'll detach more.
On top of that, the generally accepted "fullbody fix" still doesn't fix most of these issues. Even one of the devs (hackspanner) commented that this fix should be avoided if possible, since the IK wasn't made that way. And to be honest, the fix is
 a bit of a hackjob, forcing the spine length to be zero like that.
Even a "fixed" avatar will only see the issues mitigated
, not fixed entirely.

Kinami

HostileLogOut: das alot of bullshit dude.

Hugo Zink

The head sinking into the chest is a very pressing issue. Please fix it ASAP.

Aman

I agree with the Clavicle bone but beyond this everything else i'm fine with as proportions for tracking is nearly impossible to do unless you do it your self Calibrating is a needed measure as they can't keep logging so much data. there is a lot of thing's they just can't fully fix

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