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# LowLevelMesh.Part

An object that describes a range of primitives to display, and their material index.

```
struct Part
```

## Topics

### Creating a low-level mesh part

[`init(indexOffset: Int, indexCount: Int, topology: MTLPrimitiveType, materialIndex: Int, bounds: BoundingBox)`](/documentation/RealityKit/LowLevelMesh/Part/init(indexOffset:indexCount:topology:materialIndex:bounds:))

Creates a low-level mesh part.

### Describing a low-level mesh part

[`var indexOffset: Int`](/documentation/RealityKit/LowLevelMesh/Part/indexOffset)

The offset, in bytes, of the first index.

[`var indexCount: Int`](/documentation/RealityKit/LowLevelMesh/Part/indexCount)

The number of indices to use for this part.

[`var topology: MTLPrimitiveType`](/documentation/RealityKit/LowLevelMesh/Part/topology)

The geometric primitive to use when rendering this part.

[`var materialIndex: Int`](/documentation/RealityKit/LowLevelMesh/Part/materialIndex)

The material index this part associates with.

[`var bounds: BoundingBox`](/documentation/RealityKit/LowLevelMesh/Part/bounds)

The model-space bounding box of this part.

## Relationships

### Conforms To

[`Sendable`](/documentation/Swift/Sendable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

---

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