blender-animation

1# Animation
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3The execution model is in `blender-core` (its `references/bpy-patterns.md` has verified keyframe/driver snippets). Rigs are in `blender-character-rigging`.
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5## 5.x data model (what changed)
6- An **Action** holds **slots** (one per animated ID) and **layers → strips → channelbags → F-curves**. A single action can animate several objects (e.g. a rig and its camera) through different slots.
7- Assign: `ob.animation_data.action = act`, then make sure `ob.animation_data.action_slot` is set (picked automatically when a suitable slot exists; otherwise `act.slots.new(id_type="OBJECT", name=ob.name)`).
8- F-curves: `cb = anim_utils.action_ensure_channelbag_for_slot(act, slot)`, then `cb.fcurves.ensure(path, index=i, group_name=...)`. `action.fcurves` **no longer exists**.
9- The simplest route is still `pb.keyframe_insert("rotation_quaternion", frame=f)`, which creates the action, slot and channelbag.
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11## Workflow (keyframe animation, studio style)
121. **Blocking**: key poses on every channel (`CONSTANT` interpolation, `bpy.context.preferences.edit.keyframe_new_interpolation_type`) on golden frames (contact, down, passing, up for walks).
132. **Breakdowns**: add in-betweens that define arcs and spacing.
143. **Spline**: switch to `BEZIER`, fix spacing in the Graph Editor, and clean overshoot. Auto-clamped handles avoid overshoot.
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