by Paul Lovy
Rigs and animates an arbitrary Blender mesh, including shapes no template covers. Deterministic Python measures the geometry, renders let vision classify it, and the skeleton is fitted from a template where one fits or built from discovered structure where none does. It then binds with bone-heat weights, generates a looping gait for any number of legs - or a travelling wave for a body with none - and exports to glTF with the playback speed the clip's own stride implies, verified by reading the written file back. Throughout it measures rather than assumes: bone axes are probed per bone because an elbow and a knee bend opposite ways, and a rig whose pose evaluation has gone stale is made to error rather than report a confident table of zeros. Since 0.6.0 it also maps any rig to spine, neck, head, tail, legs and arms and poses it by target with IK - the engine behind animate-anything. Since 0.8.0 walks, trots and sprints are derived from ground contacts: a support plane through the measured feet, Froude-scaled stride and duty factor, and per-leg reach solved on that plane - so a sprint reaches and flies instead of replaying a walk faster - and the exporter measures speed on the planted feet. Since 0.9.0 wings are a body part: found from the skin (a sheet, not a tube) or from names, told apart as membrane or feathered, folded through the avian elbow-wrist linkage with one number, and flown - wingbeat, cruise, glide and stall speeds from wing area, span and mass, and spread, flap, glide, dive, take-off and landing clips checked for wings through the body or across the midline. Since 0.10.0 mouths are a body part: found on the skin as a cavity entering the head, given a jaw, throat and gular pouch, tongue chain and a non-deforming mouth socket, skinned by splitting the head along the lips and relaxing the split for stretch, with the gape limited to what the skin takes without folding - and bite, roar, fire-breath, swallow, engulf and purge clips checked for stretch, folded faces, rigid teeth and socket aim. Since 0.11.0 fish swim: fins are found on the skin by thickness and classified by where they attach, a fish with no rig is given a spine and a fan of ray bones per fin, and the body is laid along a travelling wave scaled by body length - stride, tail beat, cruise and burst speed from published scaling, five modes from eel to whale - with swim, sprint, glide, hover, turn, C-start and brake clips checked for tail sweep, a tailward wave and skin folding. Since 0.12.0 bodies with no front or back are an archetype of their own: the identification report measures an axis the body turns onto itself about and its order, a jellyfish, sea star, brittle star or anemone is split on the skin into a hub and a ring of appendages - loose tentacles included - and rigged with a hub, bell ribs and a chain per appendage, weighted from its parts without bone heat; a bell pulses at the rate its diameter implies and steers by closing one side harder, a sea star crawls on its tube feet in any direction, a brittle star rows behind whichever arm is nearest, and an anemone sways and retracts, every clip checked for margin closure, symmetry, tentacle lag and crossing, tips on the floor and stroke direction. Since 0.13.0 hoppers are a body plan of their own: a cricket's or rabbit's legs are found by walking up the skin from each ground contact, their joints are the corners of that walk's centreline - a heel walked separately when a flat foot hides where the shin rises, and joints buried in flesh placed from published proportions - and a pelvis-rooted rig is weighted from the parts; a rabbit hops and half-bounds on measured ankle angles through a femur-parallel-to-metatarsus leg with every planted foot at one belt speed, a cricket walks on tripods, and both jump as a launch, an engine-owned ballistic flight and a landing, checked for take-off angle, knee extension, seams and skin. Since 0.14.0 checks refuse instead of passing quietly: keys stay on the rotation channel a bone actually uses, the floor check ignores bones that carry no skin, and every clip is played back again before export - floor, skin, seam, foot slide, balance - so a layer added after authoring cannot slip through; a walk that moves nothing is refused. cycle takes max_drop, stance_width, named posture (pelvis, flex, neck in degrees toward the front, no rotation signs), an upper body solved inside the clip (arm swing opposite the legs from each arm's rest bend plane, pelvis turn and list, chest counter-rotation, a steady head) and gait styles such as elderly_shuffle, heavy and child; bake_for_game prepares a shape-keyed, over-weighted body for glTF, renders can share one scale, and a Godot MovesController reads the .moves.json manifest directly. Since 0.28.0 a body has mass: per-bone mass, centre of mass and inertia measured from the skin and stored in each bone's own rest frame, where they are constants - the whole body exactly from its surface, and the partition between bones volumetrically, because a weighted surface integral does not partition a volume and silently drags one limb's share into another's. Inside is a winding number rather than a parity, since a body arrives as overlapping shells that disagree about which way is out, and the two measurements are reported against each other so a mesh that is not closed says so instead of quietly reporting a plausible wrong number. Since 0.29.0 the shoulder girdle moves: each shoulder drops as its own side takes the body's weight and swings forward with its own arm, a fraction of a cycle behind both, so a walk has two shoulder dips a stride rather than a chest locked to the arms - a girdle hangs off the axial chain instead of sitting on it, so it is posed by turning that one bone about the body map's axes, before the arms are solved so each arm rides its shoulder. Since 0.30.0 the trunk is coupled through a transfer function rather than a multiplier: the thorax chases the pelvis by the lag a driven damped oscillator would have at the stride frequency, so its sign is nowhere written down - half a cycle of lag IS anti-phase, and it emerges as the fast limit. Pelvis-thorax relative phase, measured off the baked clip and reported per gait, now sweeps from near in-phase at a slow walk toward anti-phase as speed rises, as it does in people, where before it was the same number at every speed. Since 0.31.0 a limb's own physics sets its timing: mass.pendulum turns the measured mass into a natural frequency (a human arm lands near 0.9 Hz and a hand near 1.6), the hand's lag behind the arm is derived from it rather than written down, and mass.angular_momentum reads whole-body angular momentum off the baked clip so that questions like how far an arm should trail its leg are settled by the residual the arms exist to cancel rather than by opinion - which is how the arm's half-cycle earned its place instead of merely keeping it.
Claude Code1 Skill