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# MTLAccelerationStructureMotionBoundingBoxGeometryDescriptor

A description of a list of bounding boxes, as motion keyframe data, to turn into an acceleration structure.

```
class MTLAccelerationStructureMotionBoundingBoxGeometryDescriptor
```

## Topics

### Creating a motion bounding box geometry descriptor

[`descriptor`](/documentation/Metal/MTLAccelerationStructureMotionBoundingBoxGeometryDescriptor/descriptor)

Creates a new bounding box descriptor.

### Specifying the number of bounding boxes

[`boundingBoxCount`](/documentation/Metal/MTLAccelerationStructureMotionBoundingBoxGeometryDescriptor/boundingBoxCount)

The number of bounding boxes in each bounding box buffer.

### Specifying bounding boxes data

[`boundingBoxBuffers`](/documentation/Metal/MTLAccelerationStructureMotionBoundingBoxGeometryDescriptor/boundingBoxBuffers)

A array of motion keyframes, each containing bounding box data.

[`boundingBoxStride`](/documentation/Metal/MTLAccelerationStructureMotionBoundingBoxGeometryDescriptor/boundingBoxStride)

The stride, in bytes, between bounding boxes in each buffer.


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