{
 "comment": "SKEL 24-joint -> mixamorig name map for Lane C's constraint retarget (pose_engine.py emits a SKEL-native BVH; Lane C maps it onto the character_kit mixamorig rig). null = a SKEL joint with no direct mixamorig target (twist/heel DoF folded elsewhere). mixamorig bones absent here (Spine1, Head, fingers, *_End) are not driven by SKEL — see notes.",
 "source_skeleton": "SKEL-24 (skel/kin_skel.py order)",
 "target_skeleton": "mixamorig (spec/mixamorig_bones.json, colon-prefixed, 65 joints)",
 "skel_to_mixamorig": {
  "pelvis": "mixamorig:Hips",
  "lumbar_body": "mixamorig:Spine",
  "thorax": "mixamorig:Spine2",
  "head": "mixamorig:Neck",
  "scapula_r": "mixamorig:RightShoulder",
  "humerus_r": "mixamorig:RightArm",
  "ulna_r": "mixamorig:RightForeArm",
  "radius_r": null,
  "hand_r": "mixamorig:RightHand",
  "scapula_l": "mixamorig:LeftShoulder",
  "humerus_l": "mixamorig:LeftArm",
  "ulna_l": "mixamorig:LeftForeArm",
  "radius_l": null,
  "hand_l": "mixamorig:LeftHand",
  "femur_r": "mixamorig:RightUpLeg",
  "tibia_r": "mixamorig:RightLeg",
  "talus_r": "mixamorig:RightFoot",
  "calcn_r": null,
  "toes_r": "mixamorig:RightToeBase",
  "femur_l": "mixamorig:LeftUpLeg",
  "tibia_l": "mixamorig:LeftLeg",
  "talus_l": "mixamorig:LeftFoot",
  "calcn_l": null,
  "toes_l": "mixamorig:LeftToeBase"
 },
 "notes": {
  "spine": "SKEL has 2 trunk joints (lumbar_body, thorax); mixamorig has 3 (Spine, Spine1, Spine2). lumbar_body->Spine, thorax->Spine2; Lane C interpolates Spine1 (or leaves identity).",
  "neck_head": "SKEL 'head' is a single thorax-relative joint -> mapped to mixamorig:Neck. mixamorig:Head is left to Lane C (identity, or a small follow of Neck).",
  "radius_calcn": "radius_* (forearm pronation/supination twist) and calcn_* (heel) have no direct mixamorig bone; their DoF fold into ForeArm/Foot in mixamorig. null = skip in the constraint map.",
  "fingers": "SKEL has no fingers -> mixamorig hand/finger bones stay undriven; fingers arrive in Lane E1.",
  "toe_end_headtop": "mixamorig *_End tips (HeadTop_End, LeftToe_End, RightToe_End) are leaf markers, not driven."
 }
}