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# init(transformationMatrix:options:mask:intersectionFunctionTableOffset:accelerationStructureIndex:userID:)

Creates a new acceleration structure instance.

```
init(transformationMatrix: MTLPackedFloat4x3, options: MTLAccelerationStructureInstanceOptions, mask: UInt32, intersectionFunctionTableOffset: UInt32, accelerationStructureIndex: UInt32, userID: UInt32)
```

## Parameters

`transformationMatrix`

The transform for placing and orienting the instance in the scene.

`options`

The options for the instance.

`mask`

A mask to use for the instance when testing a ray against the geometry.

`intersectionFunctionTableOffset`

An offset to apply to the intersection function table when testing a ray against the instance.

`accelerationStructureIndex`

The index of the acceleration structure to use for the instance.

`userID`

The user identifier for the instance.

## Discussion

---

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