Describes any number of skinning bone weights that affect a vertex in a mesh.
Bone weights must be in descending order, and add up to 1.
Note that the older BoneWeight struct, and the associated Mesh.boneWeights and Mesh.GetBoneWeights APIs, describe exactly 4 bone weights per vertex. It is preferable to use BoneWeight1 and its associated APIs; they offer more flexibility, and might result in small performance benefits as Unity does not have to perform unnecessary conversion operations.
For meshes that have more than 4 bones per vertex, you must use this struct. For all other meshes, there is no performance disadvantage to using this struct, and it might result in small performance benefits as Unity does not have to perform unnessary conversion operations to describe vertices with exactly 4 bone weights.
See Also: Mesh.SetBoneWeights, Mesh.GetAllBoneWeights, Mesh.GetBonesPerVertex, Mesh.boneWeights, Mesh.GetBoneWeights, ModelImporter.maxBonesPerVertex, QualitySettings.skinWeights, SkinnedMeshRenderer.quality.