---
title: MTLAccelerationStructureInstanceDescriptorType.indirect
framework: metal
role: symbol
role_heading: Case
path: metal/mtlaccelerationstructureinstancedescriptortype/indirect
---

# MTLAccelerationStructureInstanceDescriptorType.indirect

An option that enables an instance descriptor memory layout the GPU can populate.

## Declaration

```swift
case indirect
```

## Discussion

Discussion This instance type corresponds to the MTLIndirectAccelerationStructureInstanceDescriptor memory layout.

## See Also

### Specifying the instance descriptor type

- [MTLAccelerationStructureInstanceDescriptorType.default](metal/mtlaccelerationstructureinstancedescriptortype/default.md)
- [MTLAccelerationStructureInstanceDescriptorType.userID](metal/mtlaccelerationstructureinstancedescriptortype/userid.md)
- [MTLAccelerationStructureInstanceDescriptorType.motion](metal/mtlaccelerationstructureinstancedescriptortype/motion.md)
- [MTLAccelerationStructureInstanceDescriptorType.indirectMotion](metal/mtlaccelerationstructureinstancedescriptortype/indirectmotion.md)