Bone tool
Draw, parent and pose the bones of a rig, directly on the canvas.
The Bone tool (J) works on the scene's Bone layer: the container that holds every bone and its bindings. Clicking with the Bone tool active and no Bone layer yet creates one for you, but only in Edit mode; in Animate mode, with no Bone layer, the tool has nothing to do.
Drawing a bone
In Edit mode, drag from empty canvas to draw a root bone with no parent. Drag from an existing bone's body instead, and the new bone is parented to it, starting where you clicked: this is how you build a chain, one drag per link. A drag shorter than a small minimum length does not become a bone; it just deselects instead.
Switch Bone Type to Static before you place one, and a click, not a drag, drops a round handle bone instead. Static bones are IK goals and control points: they can be positioned and keyframed, but they do not deform anything themselves.
Selecting and parenting
Click a bone's body to select it. Shift adds more to the selection, but only among bones of the same kind: you cannot multi-select a Stretched bone together with a Static one.
Turn on Reparent, then drag a bone onto a new parent to move it in the hierarchy. Celas Studio refuses a drop that would make a bone its own ancestor, and rebases the bone's stored angle keyframes so its current pose does not jump when the parent changes.
Tool options
| Option | Default | Shown when | What it does |
|---|---|---|---|
| Bone Type: Stretched / Static | Stretched | Edit mode only | Chooses what the next drag or click creates |
| Move | off | always | Drag an existing bone to reposition it, instead of sprouting a new one from it |
| Reparent | off | Edit mode only | Drag a bone onto a new parent |
| Snap | off | Edit mode only | Snap a dragged endpoint onto another bone's start or end point |
Bone Type: Static, Move and Reparent are mutually exclusive: turning one on switches the other two off. Snap is independent and can be combined with any of them; holding Ctrl or Cmd also snaps a bone endpoint transiently while you draw, even with Snap itself turned off.
Endpoint and stretch handles
A selected bone's start and end grips appear while you hold Alt, or while Move is on. Drag one to change the bone's length and angle: its children counter-rotate so they hold their pose rather than visibly snapping.
In Animate mode a small square handle appears a short way from the tip of the selected bone; drag it to stretch the bone without changing its rotation.
Rest pose vs. Animate mode
Edit mode poses the rig's rest skeleton: moving or rotating a bone there changes its base pose, ripples down to every child, and affects any frame that has no keyframe of its own. Animate mode poses one specific frame: dragging a bone's body there rotates it around its parent joint, and the result is stamped as a keyframe on release when that channel's auto-key is armed.
Right-click deselects every bone. There is no bone context menu and no double-click behaviour.
| J | Bone tool |
| Delete or Backspace | Delete the selected bones (Edit mode) |
| Ctrl or Cmd, while dragging | Snap the endpoint onto another bone, even with Snap off |
| Ctrl or Cmd, dragging a Static handle | Snap the handle onto a bone's pivot |