Rigging

A Rig is an animation control system for a Model. Rigs can use different methods for animating. For example it is possible to animate a mesh only by using empties and constraints, so no single bone is involved, yet it is an animation system.[break] The most common form of Rigs is based on Bones. This special form of a Rig is also named Armature.[break] Rigging is the process of creating the Rig.

Note: The Term “Rigging” is often also used as a synonym for Skinning (see below). We also find the term “Rigged Mesh” for example, which would actually be more accurately named “Skinned Mesh”. It is also very common to talk about “Rigged Characters”. Depending on the context it is often clear what is meant.[break] However since in Blender we clearly have to distinguish the processes and workflows, we should also use precise terminology. Thus we distinguish between Rigging (make the rig) and Skinning (weight the mesh).

Rigging Panel (Tool shelf)

[PS Showtime url=”/wp-content/uploads/2014/09/map_rigging.png”]

The rigging panel basically contains a collection of properties which also are available at other regions in Blender. But having them all in one place is a time saver. The panel is provided It has 4 major sections:

• Bone Display style.
• Control Bone Visibility.
• Active Deform Bones
• Bone Deform Settings
• Bone Constraints
  

(1) Bone constraints and Bone Deform Settings are only visible in Edit Mode and Pose mode.

The first row of buttons changes the bone shape. You probably will mostly select the Octahedron Style or the Stick Style.

The first row of the Bone Visibility section contains 4 Presets for different Workflows:

• Skin (the Weighting Workflow).
• Pose (the Animation Workflow).
• Retarget (import of BVH Animations).
• Edit (Modify the Rig).

• Skin is used when you want to do weight painting on your Mesh. This preset will enable the SL Bones and also unblocks their rotation setting so that you can rotate the bones for testing your weights.
• Pose is used for all your animation work. This preset enables the green control bones which are optimized for your Animation tasks. This is also the default preset forAvastar.

• Retarget is used when yuo want to import another Animation from a BVH file.
• Edit is used when you want to edit the Bone’s Rest poses, for example when you create a non human character.

The Bones are grouped into 3 categories (Control Bones, Deform Bones and Active Deform Bones) and 13 subsets  You can enable/disable the visibility of each subset separately by enabling the corresponding view button (see yellow box in image).
Note: The Bone Visibility Panel can be collapsed and expanded by clicking on the small arrow sign to the left of the Bone Presets.
Avastar Bone Sets are described below in more detail.

Control Bone Groups

• Torso, Arms, Legs, Origin: These buttons control which of the Control Bones (green) are visible
• IK Arms, IK Legs: These buttons control which of the IK Bones (yellow) are visible
• Extra: There are a few Extra bones which normaly are not used for Animation in SL. These bones are either not weighted to the default Avatar (Skull, Foot Bones and Toe Bones) or are automatically animated (Eye Bones). However you can use these Bones in your animations for custom meshes.
• Attachment: to display the Attachment Bones (red)
• Structure: to display the Structure bones
• Eye Target: to display the Eye target (needed for animating the eyes)

Deform Bone Groups

Display all bones which have the Deform Option enabled. The content of this set can change dynamically (see fitted Mesh)

• SL Base: to display the SL Bones (Blue)
• Volume: to display the Volume Bones

Active Deform Bones

The Active Deform Bones are Bones which have the “Deform Flag” set. Only Active deform Bones can modify the mesh (via skeletal animation)  when they have an associated Weightmap.

Note: You can not disable the visibility of ALL bone groups. Hence at least one of the bone groups is always selected.

Note: Selected elements (dark background) are made visible, while unselected elements get hidden.

The Active Deform Bones can be filtered by 3 categories:

• SL: The 26 Animation Bones for SL
• Vol: The Collision Volume Bones
• Map: All deform bones which also have Weightmaps (only shown when a mesh is selected)

• Deform: Disable or Enable the selected Bones as Deform Bones.
• SL: Disable or Enable the entire set of SL Base Bones as Deform Bones
• Vol: Disable or Enable the entire set of Collision Volume Bones as Deform Bones

• When you Skin your Mesh (When you do weight painting tasks) then you almost always want to unlock the Bone Rotations of the Blue SL Base Bones. Then you are free to pose the Deform bones for testing purposes.
• When you Animate your Character, then you may want to unlock the Location Constraints of the Green Control bones, so that you can also perform Location animations.

• Bone Constraints Selector: Here you can specify if you want to affect
  • All Pose Bones
  • All Visible Pose Bones
  • All Selected Pose Bones
• SL Bone Rot: Lock/Unlock the rotation of the SL Base Bones (good for weighting tasks)
• Control Bone Loc: Lock/Unlock the Location of the Control Bones (good for special animations i.e. face animation)

The Avastar Rig also contains a set of Structure Bones, although there are no corresponding SL Base Bone available. The structure Bones are mostly beneficial for Animation when you create non Human characters like Quadrupeds for example (dogs, cats, lions, horses, …)
By default the Structure Bones are not selectable. But when you work on non human skeletons you often want to reposition the structure bones as well.

This is where the Structure Enable button comes into Play. When you enable Structure you can move the Structure Bones around just like all the other Control bones.

The Snap Rig to Pose button is a quick way to make the current Pose the new Rest Pose.

The Snap Base to Rig button allows to snap the SL Base Bones to the Control bones. You need this function whenever you have modified your Rig in Edit mode.

Right after you have clicked on the Button an operator panel will show up at the bottom of the Tool Shelf (lower left corner). You might need to scroll down the Tool shelf to spot that panel:

Pole Angle show up when you are working with IK Targets. It is important to have the Pole angle set correctly because otherwise you will see remarkable changes of your pose when you switch between FK and IK mode.