threejs buffergeometry and skeleton clone

for skinning we have set the 'skinIndex' and 'skinWeight' attribute for geometry ¹

normal attribute for lighting position attribute for position skinIndex indexs of bone position skinWeight weight of bone

if the geometry is indexed geometry, when we have clone the geometry we have to set index

const indexed = new BufferAttribute() // index buffer attribute
const geometry = new THREE.BufferGeometry()
geometry.setIndex(indexed)

geometry.setAttribute('position', attributefuffer) // fake code for setting attribute
geometry.setAttribute('skinIndex', attributefuffer) // fake code for setting attribute
geometry.setAttribute('skinWeight', attributefuffer) // fake code for setting attribute
geometry.setAttribute('normal', attributefuffer) // fake code for setting attribute

to create and bind skeleton

const bones = [bone, bone] // list of bones
const skeleton = new THREE.Skeleton(bones)
const skinmesh = new THREE.SkinnedMesh( geometry, material);
skinmesh.add(bones[0]) // add root bone to scene or add to parent
skinmesh.bind(skeleton)

skinmesh bind with default as 'attch' mode, would bind the mesh's worldmatrix, which result the mesh will stick to the skeleton position