---
title: MTLAccelerationStructureSizes
framework: metal
role: symbol
role_heading: Structure
path: metal/mtlaccelerationstructuresizes
---

# MTLAccelerationStructureSizes

The expected sizes for a ray-tracing acceleration structure.

## Declaration

```swift
struct MTLAccelerationStructureSizes
```

## Topics

### Retrieving the sizes

- [accelerationStructureSize](metal/mtlaccelerationstructuresizes/accelerationstructuresize.md)
- [buildScratchBufferSize](metal/mtlaccelerationstructuresizes/buildscratchbuffersize.md)
- [refitScratchBufferSize](metal/mtlaccelerationstructuresizes/refitscratchbuffersize.md)

### Creating an acceleration size structure

- [init()](metal/mtlaccelerationstructuresizes/init().md)
- [init(accelerationStructureSize:buildScratchBufferSize:refitScratchBufferSize:)](metal/mtlaccelerationstructuresizes/init(accelerationstructuresize:buildscratchbuffersize:refitscratchbuffersize:).md)

## Relationships

### Conforms To

- [BitwiseCopyable](swift/bitwisecopyable.md)
- [Sendable](swift/sendable.md)

## See Also

### Creating acceleration structures for ray tracing

- [makeAccelerationStructure(descriptor:)](metal/mtldevice/makeaccelerationstructure(descriptor:).md)
- [makeAccelerationStructure(size:)](metal/mtldevice/makeaccelerationstructure(size:).md)
- [accelerationStructureSizes(descriptor:)](metal/mtldevice/accelerationstructuresizes(descriptor:).md)