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Manual - Blender 2.45

[edit] Editing Armatures

[edit] Description

Armatures are comprised of Bones. Editing an Armature in Edit Mode allows you to manipulate the bones in their default rest position.

[edit] Options

Edit panel: Bones.

BO:

Rename your bone.

Child of

Child of

Dropdown: Lets you choose which bone will be the parent of this bone. If so there will be a small button "co" meaning connected. This will set the relationship between your bones. If you parent it to another bone, it will do everything the parent does, rotate, move and scale. A dotted line between the parent and child will appear. If you select Connected, the Root of the Children will stick to the tip of the parent, giving you a chain of bones like the 2 bones in your arm. (Child of)

Segmented Bone

Segm

This is the option to use B-Bones. Set to something > 1, it will cut your bone in many little segments and will deform them on a bezier curve. It really show off in a chain of bones though. See the example between 1 segment (right) and 3 segment each (left). (I returned in Object mode to see the effect). (Segmented Bone)

Envelope

Dist

This is the area of influence of the bone. it can be visualized using the Envelope display mode. We generally don't touch this field as there is a more easy and fast way to change this option. Turn Envelope drawmode on and select a bone. Then using AltS, you can scale the zone of influence. Better: you can do it on multiple bones and you can do it in EditMode and PoseMode. (Envelope)

Weight

Weight

This gives you the liberty to tell if this bone will work more or less on the geometry. For example if you have 2 bones working with envelope and crossing each other, you can tell one of them to get more power by lowering the weight of the bone you don't want to use much. If both bones have the same weight (like 1:1) they will influence the geometry equally. But if you set one to 0.5. The other one at 1 will influence more. For example in this image, 2 bones using envelope influence try to move the same geometry. The 2 on the left have the same weight, you can see the geometry didn't move. On the right one of the bones has 0.5 so the bone with 1 of weight is winning the pulling contest!. (Weight)

Hinge

Hinge

This tells the bone to remain motionless in a chain. It doesn't copy the rotation and scale of the parent. Useful for mechanical rig I would say, as you can animate the rotation of the hinge bone without having to correct it because the parent rotated. (Hinge)

Deform

This lets you tell if you want the bone to deform at all. It's like setting weight to 0, except it's faster this way. Useful when using a bone as a target or a controller, i.e. a bone you just want to use to work on other bones.

Mult

To deform geometry you can use vertex group and/or Envelope. The fact that you can mix both ways gets interesting when you can use one to better tweak the other one. Like using envelope everywhere but tweaking a difficult place manually with vertex group. It's gonna be shown more in details in the Skinning section.

Hide

This option lets you hide the bone. You can use it to hide useless bones when you try to see what you're doing or just to get a functional rig for an animator when everything is done, kind of "hiding the useless". For example, when you animate you don't need the entire chain of the leg, just the controllers. This option is valid for both EditMode and PoseMode. It's possible to directly Hide bones in the 3Dview by selecting the bones to hide and do H. You can turn all bone visible with AltH too.

[edit] Selecting Bones

[edit] Description

Bone parts

Bones in Edit mode consist of the tip (the end pointing to) and the root (the end pointing from), and these can be moved independently. RMB clicking on the tip or the root selects either, or clicking on the bone's body selects the entire bone. Selecting both the tip and root selects the entire bone implicitly.

L selects a chain of connected bones under the mouse pointer

P selects the parent bone of selected bones. This is useful when using a fullscreen 3d-View, so an Outliner view is not required to be able to select the parent bone(s). This also works in pose mode.

[edit] Adding and Deleting Bones

[edit] Description

In Edit mode, you can add a new bone at the cursor location via the Add menu (⇧ ShiftA).

E extrudes a new bone from a selected root or tip. This will create a bone connected to the original one, meaning the Root of the new bone will follow the Tip of the original one. You can also CtrlLMB to extrude a new bone. It will extrude to where you clicked.

⇧ ShiftD duplicates selected bones. An entire bone must be selected, not just the root or tip.

X deletes selected bones

[edit] Interactively Setting Bone Roll

[edit] Description

Setting the roll value of bones manually has always been a chore. Sometimes, especially on more complex rigs, it may be necessary to manually assign the roll values. However, adjusting the roll value could only be done for one bone at a time, and it was difficult to gauge what the right amount to adjust it was.

Now there is a new transform mode/tool in EditMode. You can select multiple bones and set their roll values interactively. It acts like rotating the bones around the local y-axes in PoseMode. For better feedback, it is recommended that you turn on Draw Axes for the Armature in question.

You can access this tool by pressing CtrlR

[edit] Subdivide

[edit] Description

You can subdivide a bone (Before/After subdivision) with the W menu. The menu gives you the following options:

• Subdivide - this simply divides the bone into two bones, as shown in the graphic.
• Subdivide Multi - this option gives you a pop-up that asks for the number of cuts. It defaults to the last value used. If you want to change one bone into five, you'll want four cuts. Use the triangles on either side to increment/decrement the field, or click on the field and enter the number you want yourself. Press the OK button when you're done to complete the operation.
• Flip Left-Right Names - Blender will try to help you name bones assuming a right/left symmetry. Sometimes, it gets right and left mixed up, use this option when you know that's going to happen, so you don't have to manually rename the bones.

Before subdivision

After subdivision

[edit] X-Axis Mirror Edit

[edit] Description

X-axis mirroring replicates edits to one side of an Armature, mirrored on the other side. This works many of Blender's armature editing tools, including manipulations such as move, rotate, scale, for extrude and subdivide. It's a clean way to just do half the job.

The axis of mirroring is X so left<-->right in frontview (1 NumPad) and the center is the center of the armature object.

[edit] Flipping Left and Right Bone Names

[edit] Description

Blender can flip left or right markers in bone names. This can be useful if you've constructed half of a symmetrical rig (marked for a left or right side) and duplicated and mirrored it, and want to update the names for the new side. Blender will swap text in bone names according to the following naming conventions.

[edit] Naming conventions

An example of left/right bone naming in a simple rig

Naming conventions in Blender are not only useful for you to find the right bone, but also to tell Blender when any two of them are counterparts.

In case your rig can be mirrored in half (i.e. it's bilaterally symmetrical), it's worthwhile to stick to a left-right naming convention. This will enable you to use some tools that will probably save you time and effort.

• First you should give your bones meaningful base-names. Like leg, arm, finger, back, foot, etc...
• If you have a bone that has a copy on the other side (a pair), like an arm, give them one of the following separators...
  • Left/right separators can be either the 2nd position (L_calfbone) or last-but-one (calfbone.R)
  • If there is an lower or upper case L, R, left or right blender handles the counter part correctly. For a list of separators see below. Pick one and stick to it as close as possible when rigging, it will pay off. For example:

Lefthand	->	Righthand
L Hand.005	->	R Hand
hand.r	->	hand.l
Foot-l	->	Foot-r
pelvis LEFT	->	pelvis RIGHT

• Before Blender handles an armature for mirroring or flipping it first removes the number extension, if it's there (like .001)
• You can copy a bone named bla.L and flip it over using W >> flip name. Blender will name the copy bla.L.001 and flipping the name will give you bla.R. Extensions such as .001 are also preserved.

Possible separators for Left-Right extensions:

• space " "
• dot "."
• minus "-"
• underscore "_"
• If no 'switch' done yet, it tries if a name starts or ends with left or right, case insensitive. It replaces this, disregarding separator.

Manual