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

Creates a new acceleration structure instance.

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

## Parameters

`transformationMatrix`

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

`options`

The options for this instance.

`mask`

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

`intersectionFunctionTableOffset`

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

`accelerationStructureIndex`

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

---

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