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# MTLIndirectAccelerationStructureInstanceDescriptor

A description of an instance in an instanced geometry acceleration structure that the GPU can populate.

```
struct MTLIndirectAccelerationStructureInstanceDescriptor
```

## Overview

This memory layout corresponds to the [`MTLAccelerationStructureInstanceDescriptorType.indirect`](/documentation/Metal/MTLAccelerationStructureInstanceDescriptorType/indirect) instance type.

---

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