# BoneWeight1

> Describes a bone weight that affects a vertex in a mesh.

## Definition

* **Type:** Struct
* **Namespace:** [UnityEngine](/engine/6000.6/script-reference/unityengine.md)
* **Assembly:** UnityEngine.CoreModule
* **Implements:** [IEquatable\<BoneWeight1>](https://learn.microsoft.com/dotnet/api/system.iequatable-1)

```csharp
public struct BoneWeight1 : IEquatable<BoneWeight1>
```

## Remarks

This struct can be used with the [Mesh.GetAllBoneWeights](/engine/6000.6/script-reference/unityengine/mesh/getallboneweights.md), [Mesh.SetBoneWeights](/engine/6000.6/script-reference/unityengine/mesh/setboneweights.md) and [Mesh.GetBonesPerVertex](/engine/6000.6/script-reference/unityengine/mesh/getbonespervertex.md) APIs to describe up to 255 bone weights per vertex.

Note that the older [BoneWeight](/engine/6000.6/script-reference/unityengine/boneweight.md) struct, and the associated [Mesh.boneWeights](/engine/6000.6/script-reference/unityengine/mesh/boneweights.md) and [Mesh.GetBoneWeights](/engine/6000.6/script-reference/unityengine/mesh/getboneweights.md) APIs, describe exactly 4 bone weights per vertex. It is preferable to use [BoneWeight1](/engine/6000.6/script-reference/unityengine/boneweight1.md) 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.

Additional Resources: [Mesh.SetBoneWeights](/engine/6000.6/script-reference/unityengine/mesh/setboneweights.md), [Mesh.GetAllBoneWeights](/engine/6000.6/script-reference/unityengine/mesh/getallboneweights.md), [Mesh.GetBonesPerVertex](/engine/6000.6/script-reference/unityengine/mesh/getbonespervertex.md), [Mesh.boneWeights](/engine/6000.6/script-reference/unityengine/mesh/boneweights.md), [Mesh.GetBoneWeights](/engine/6000.6/script-reference/unityengine/mesh/getboneweights.md), [ModelImporter.maxBonesPerVertex](/engine/6000.6/script-reference/unityeditor/modelimporter/maxbonespervertex.md), [QualitySettings.skinWeights](/engine/6000.6/script-reference/unityengine/qualitysettings/skinweights.md), [SkinnedMeshRenderer.quality](/engine/6000.6/script-reference/unityengine/skinnedmeshrenderer/quality.md).

## Properties

| Property                                                                          | Description               |
| --------------------------------------------------------------------------------- | ------------------------- |
| [boneIndex](/engine/6000.6/script-reference/unityengine/boneweight1/boneindex.md) | Index of bone.            |
| [weight](/engine/6000.6/script-reference/unityengine/boneweight1/weight.md)       | Skinning weight for bone. |