Adjusting the scale of rigged mesh (macro/micro avatars)

[Wulfie Reanimator]

Hopefully the title gives a clear enough idea of what I'm talking about.

I'm using Blender 2.8 with Avastar, and what I want to know is if there's some kind of deformer (animation) that I can create which would not only adjust the length of bones, but the "volume" of the bone as well.

For example, let's say you have a Maitreya body (editing the mesh is not an option), and you want to make a bigger version of it than regular sliders would allow. Simply changing the length of each bone wouldn't work, since you'd look like some kind of new-wave Slenderwoman. Each part of the body that gets stretched would also have to get proportionally "thicker" so it would still look proportional.

I noticed the rig has Collision Volume bones, and I know/think they're related to the sliders, but can I scale them on their own? So any mesh that gets attached would be "scaled" as well? Is there an clean process to this (making sure things don't get distorted), or am I stuck with trial and error?

Edited July 9, 2020 by Wulfie Reanimator

[OptimoMaximo]

Simple answer: no you can't do that.

Longer version:

Sliders control the scale and position of collision volume bones on a per-value basis ie 50 equals a certain offset from the parent and a certain scale on a set of bones, regular and collision. Some body sections like the neck don't even use that but rely on the regular bone scale. Joint scale is completely controlled by the system, except for the pelvis bone. Indeed, scale animation isn't supported at all by the animation file format, except for the pelvis which COULD bear scale animation, but it's something that both Gaia for Avastar and I for MyAniMATE have decided to not support, for various reasons. @polysail, the maker of a similar plug in for 3dsmax apparently supports it (at least as far as I can remember if I'm not mistaken) and might give us some insights as per scale animation on the pelvis bone pros and cons. 

Edited July 9, 2020 by OptimoMaximo

[Wulfie Reanimator]

1 minute ago, OptimoMaximo said:

Simple answer: no you can't do that.

Longer version:

Sliders control the scale and position of collision volume bones on a per-value basis ie 50 equals a certain offset from the parent and a certain scale on a set of bones, regular and collision. Some body sections like the neck don't even use that but rely on the regular bone scale. Joint scale is completely controlled by the system, except for the pelvis bone. Indeed, scale animation isn't supported at all by the animation file format, except for the pelvis which COULD bear scale animation, but it's something that both Gaia for Avastar and I for MYANIMATE have decided to not support, for various reasons. @polysail, the maker of a similar plug in for 3dsmax apparently supports it (at least as far as I can remember if I'm not mistaken) and might give us some insights as per scale animation on the pelvis bone pros and cons. 

Thank you. That makes sense, considering how rare it is to see avatars that are unusual in height. So to accomplish that, you would need to create the mesh body and the deformers to go with it, and that's not practical for me (and most people I imagine).

Regarding the pelvis scale, you made it sound like scaling the pelvis could affect the whole skeleton. Is that the case (if it was supported and we ignored all the potential drawbacks)? Otherwise it would be kind of odd to mention the scaling of a single bone.

[OptimoMaximo]

7 hours ago, Wulfie Reanimator said:

Regarding the pelvis scale, you made it sound like scaling the pelvis could affect the whole skeleton. Is that the case (if it was supported and we ignored all the potential drawbacks)? Otherwise it would be kind of odd to mention the scaling of a single bone.

Uniform scaling on the root bone affect the whole hierarchy, yes. There is one more joint in the skeleton definition that the system doesn't let us use, called Root, placed at floor height in between the feet that might be useful for that purpose though.