About Bones

The most important thing to know!

Before we go ahead with our Mesh inspections i want to make a quick sidestep to introduce one of the most confusing properties of the Avastar Rig. That is its separation into Sub rigs. In this chapter i will only introduce the Deforming Rig and the Animation Rig

  • Animation Rig
  • Deforming Rig
  • Fitted Mesh Rig
  • Attachment Rig
  • IK Control Rig

A serious recommendation

If you want to understand the technical details of the rigs and their properties, then you find  number of good documents about the Principles of skeletal Animation on the Web.

We recommend you to take a bit of time to learn what that is and how it works. You will almost certainly fail with your projects when you do not know exactly what we are talking about!

The Animation Rig

This rig is used for creating Animations. The rig has been setup to allow you moving the bones around more or less as you like. The Limb bones are organized in chains, so when you grab one bone by using the ‘G’ key on the keyboard, you can move the related limb around in a natural way.

For the Experts: The Animation Rig does not contain any weighting information. But the deform rig (see below) is coupled to the Animation rig by location constraints.


The Deforming Rig

This rig is only used for weighting purposes. When you bind your meshes to the Avastar Rig, then you actually bind them only to the Deform Rig. Avastar does this automatically for you.

[For the Experts: The Deform Rig is equivalent to the Skeleton of the SL Avatar. The Bones are named like the SL Bones and they are connected and positioned exactly in the same way as they are used in the SL Viewer.

The Fitted Mesh Rig (Volume Bones)

The Fitted Mesh Rig is a set of bones which originally have been used only for defining touch regions for the Mouse cursor. But technically they also can be used for weighting as well.And since they are related to the SL Shape Slider system, they atually can be used for shaping.

However, the name Fitted Mesh has to be taken with a grain of salt. The name implies that the meshes behave in the same way as the SL System character, the common expectation is that fitted mesh always fits to the Avatar Body regardless of the Shape Slider values. But sadly this is actually not at all true!

The Attachment Rig

The attachment bones indicate the locations where you can attach Prims or Custom mesh to your character. Those bones are animateable and they can also be used for weighting.

Beware: Weighting of attachment bones works but it is not officially supported by Secondlife! We recommend to not use weighted attachment bones.

The IK Rig

The IK Rig is unique to the Avastar Rig. This rig is only used for IK-animation (Inverse Kinematic). we provide IK for:

  • Arms
  • legs
  • hinds
  • face (*)

The Face IK Rig is actually not a true IK rig but it used is very much like the IK Rig, so lets keep this here for now.

The Rig Display Panel

You can choose which parts of which rig are shown in the Blender 3D View. For this purpose we have created the Avastar Rig Display Panel.

You find 4 bone sections here:

  • The Animation Bone groups control which parts of the Animation Rig are visible
  • The Deform Bone Groups specify which parts of the Deform Rig are shown
  • The Special Bones Group enables the visibility of bones which are not used so frequently. Note: The Extra Bones also contain the System eyes
  • In the active deform Bones part you can either show the entire Deform Rig, or you can filter by bone type. We will see later how you can use the filter system to only show the weighted deform bones of the active/selected Meshes

Please play a bit with the panel to get used to where is what. And please always follow the rules:

The Animation Rig is only used to animating your Rig. It is never used for deforming(weighting) your Meshes

The deform Rig is only used for Weighting your meshes to the Rig. Although we added limited functionality to pose the Deform Rig this rig should never be used for animating your meshes.


Next — Inspect Weights