The hold was wrong on every character in three independent ways, all of
them a constant standing where a measurement belonged.
MOUNT. set_weapon seated the weapon with rotation_degrees = (0, 90, -90).
A bone attachment is expressed in the BONE's axes and no two rigs agree on
those, so one constant mounted the gun differently on every model. It never
needed to be right — the pose layer aims by rotating the wrist until the
weapon's forward lies on the aim line, so the identity means "forward is
the hand bone's -Z", true on any rig, and the wrist absorbs the roll.
SIZE. The set is modelled at real-world scale; an M4 is 0.84 m butt to
muzzle and these characters have 0.47 m arms against an adult 0.52. That
put the handguard 0.66 m from the support shoulder, 0.2 m past reach, so
the support hand was slid back down the weapon until it fitted — on Taila
from an authored 0.35 m to 0.083 m, which puts both fists together at the
grip. Two hands on a pistol, not a rifle.
Fixed by solving the support arm's triangle rather than picking a factor:
its hand must reach stock+fore ahead of the pocket from a shoulder half a
shoulder-width off the axis, so scale the gun to the largest that keeps the
handguard inside that reach. Taila and Kiyoko now come out at their own
scales (0.217 and 0.213 m of hand separation) with the support hand at its
FULL authored handguard distance and the slide-back loop never firing. The
loop also has a floor now: a straight support arm beats no handguard hold.
FINGERS. Nothing posed them — every hand was flat and open, which is the
loudest possible tell that a character is not holding anything. They close
now, about an axis derived from each hand's own anatomy in the rest pose:
along = wrist to middle knuckle, palm = middle knuckle to thumb tip (the
thumb opposes the fingers, so it marks the palm side by construction), curl
= along x palm. The trigger finger gets a much shallower curl than the
rest, because it lies along the trigger.
Finger bones resolve by ROLE across all three naming families met so far —
Rigify DEF-f_index.01.L, VRoid J_Bip_L_Index1, Blender IndexFinger1_L —
ordered by depth below the hand rather than by the number in the name,
which is not consistent between them.
Verified by render on Taila and by measurement on Kiyoko: stock at the
shoulder, trigger hand on the grip, support hand out on the handguard,
fingers wrapped, arms not crossing. Smoke 0 failures.
Co-Authored-By: Claude Opus 5 <[email protected]>
Kiyoko, Hikari, Aria and Momo, all CC-BY from Sketchfab, licences recorded
beside each skin. Seven GLB characters selectable now.
kiyoko 13 meshes 20 cloth chains (62 bones) 0.0% cross-leg bleed
aria 15 meshes 15 cloth chains (37 bones) 0.0%
momo 5 meshes 9 cloth chains (35 bones) 0.0%
hikari 13 meshes 10 cloth chains (37 bones) 0.2%, 12 twist bones
These are the first characters imported that were NOT authored against the
library's own bone spelling, and every one of them broke something that
had been quietly wrong all along. All four failures were in code that
guesses anatomy from names, which is exactly what tools/rig_map.py exists
to stop doing:
- LIMB ROLES went to the first role in LIMB_ORDER that matched at all, so
shin's catch-all "leg" claimed UpperLeg before thigh's exact "upperleg"
was ever consulted, and the thigh went unassigned. The result depended
on the order bones arrived in. Claims are now granted longest-stem
first. This also broke Mixamo (LeftUpLeg/LeftLeg) and had simply never
been hit, because every character so far used Rigify DEF- names.
- Names cannot settle thigh-vs-shin at all. A bare "leg" is the SHIN on
Mixamo and the THIGH on a rig whose shin is "knee" — both common, same
token, opposite bones. RigRoles now walks the leg from the foot upward
and fills in whatever the names could not, stepping over twist bones.
- verify_character.py looked for legs by the substrings "thigh"/"shin",
which VRoid spells UpperLeg/LowerLeg. It declared every locomotion clip
static while the legs animated perfectly, and the cross-leg bleed check
found no leg vertex groups at all and passed vacuously. Two green-
looking lies from one missing lookup; both now read the sidecar's
resolved roles.
- The cosmetic/spring classifier matched whole tokens only, so Momo's
HairFL / HairFR / HairF_Top tokenised to "hairfl" and matched nothing.
She imported with six chains, all bust, and no hair. Both classifiers
now share one rule that also accepts a two-character positional suffix,
which is short enough that "forearm" and "earring" are still untouched.
Two more pipeline fixes:
- A source model's own clips leaked into the export. Clearing bpy.data
.actions before the library import is not enough — hikari carried two on
a second armature's NLA tracks, and NLA_TRACKS export mode ships
anything in a track anywhere in the file. They export as rest-pose
statues. Now everything not retargeted is stripped from every object.
- verify_character.py gained a check for cloth chains with no measurable
extent. A chain whose bones are zero-length is dropped by the runtime
and simulates nothing, while the sidecar still cheerfully reports it.
Known: hikari's ten cloth chains are all zero-length and her collider fit
found nothing, so her costume does not simulate — her rig has been through
two toolchains and its cosmetic bones are empty terminators. She animates
correctly otherwise. The new check now reports this instead of hiding it.
tools/retarget.py also carries local working-tree changes that predate
this session.
Co-Authored-By: Claude Opus 5 <[email protected]>
Nicholas Butzke