描述 4 个影响网格顶点的蒙皮骨骼权重。
Elements in this struct must be in descending order of weight value. The sum of all weight values must be 1. If a vertex is affected by fewer than 4 bones, each of the remaining weight values must be 0.
Note that this struct, and the associated Mesh.boneWeights and Mesh.GetBoneWeights APIs, describe exactly 4 bone weights per vertex. The newer BoneWeight1 struct describes a single bone weight, and it can be used with the associated Mesh.GetAllBoneWeights, Mesh.SetBoneWeights and Mesh.GetBonesPerVertex APIs to describe up to 255 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 unnessary conversion operations.
另请参阅：Mesh.boneWeights、Mesh.GetBoneWeights、Mesh.GetAllBoneWeights、Mesh.SetBoneWeights、Mesh.GetBonesPerVertex、ModelImporter.maxBonesPerVertex、QualitySettings.skinWeights、SkinnedMeshRenderer.quality。
| boneIndex0 | 第一个骨骼的索引。 |
| boneIndex1 | 第二个骨骼的索引。 |
| boneIndex2 | 第三个骨骼的索引。 |
| boneIndex3 | 第四个骨骼的索引。 |
| weight0 | 第一个骨骼的蒙皮。 |
| weight1 | 第二个骨骼的蒙皮。 |
| weight2 | 第三个骨骼的蒙皮。 |
| weight3 | 第四个骨骼的蒙皮。 |