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# USDPlayer.MeshData.Update

Delta update carrying only the mesh fields that changed since the last frame.

```
struct Update
```

## Topics

### Instance Properties

[`let assignedMaterials: [USDPlayer.MaterialID]?`](/documentation/USDKit/USDPlayer/MeshData/Update/assignedMaterials)

Updated material bindings.

[`let id: USDPlayer.MeshID`](/documentation/USDKit/USDPlayer/MeshData/Update/id)

Unique identifier for the mesh being updated.

[`let indexData: Data?`](/documentation/USDKit/USDPlayer/MeshData/Update/indexData)

Updated index buffer data.

[`let instanceTransforms: [float4x4]?`](/documentation/USDKit/USDPlayer/MeshData/Update/instanceTransforms)

Updated world-space instance transforms.

[`let meshType: USDPlayer.MeshData.MeshType?`](/documentation/USDKit/USDPlayer/MeshData/Update/meshType)

Updated mesh type.

[`let parts: [LowLevelMesh.Part]?`](/documentation/USDKit/USDPlayer/MeshData/Update/parts)

Updated mesh parts.

[`let vertexData: [Data]?`](/documentation/USDKit/USDPlayer/MeshData/Update/vertexData)

Updated vertex buffer data.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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