<!--
{
  "availability" : [
    "iOS: 14.0.0 -",
    "iPadOS: 14.0.0 -",
    "macCatalyst: 14.0.0 -",
    "macOS: 11.0.0 -",
    "tvOS: 16.0.0 -",
    "visionOS: 1.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "Metal",
  "identifier" : "/documentation/Metal/MTLComputeCommandEncoder/setAccelerationStructure(_:bufferIndex:)",
  "metadataVersion" : "0.1.0",
  "role" : "Instance Method",
  "symbol" : {
    "kind" : "Instance Method",
    "modules" : [
      "Metal"
    ],
    "preciseIdentifier" : "c:objc(pl)MTLComputeCommandEncoder(im)setAccelerationStructure:atBufferIndex:"
  },
  "title" : "setAccelerationStructure(_:bufferIndex:)"
}
-->

# setAccelerationStructure(_:bufferIndex:)

Binds an acceleration structure to the buffer argument table, allowing functions to access it on the GPU.

```
func setAccelerationStructure(_ accelerationStructure: (any MTLAccelerationStructure)?, bufferIndex: Int)
```

## Parameters

`accelerationStructure`

An [`MTLAccelerationStructure`](/documentation/Metal/MTLAccelerationStructure) instance to bind to the argument table.

`bufferIndex`

The index the structure binds to in the argument table.

## Discussion

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)