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# MDLMeshBufferZoneDefault

A standard implementation of the [`MDLMeshBufferZone`](/documentation/ModelIO/MDLMeshBufferZone) protocol.

```
class MDLMeshBufferZoneDefault
```

## Overview

Model I/O uses zones to ensure that related allocations—such as the multiple vertex and index buffers associated with a [`MDLMesh`](/documentation/ModelIO/MDLMesh) object—use contiguous blocks of memory for optimal performance. When working with a [`MDLMeshBufferAllocator`](/documentation/ModelIO/MDLMeshBufferAllocator) object that does not implement its own zone management, Model I/O uses this zone class.This class declares no methods or properties of its own. For the key functionality of all mesh buffer zone objects, see [`MDLMeshBufferZone`](/documentation/ModelIO/MDLMeshBufferZone).

## Relationships

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

### Conforms To

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

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

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

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

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

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

[`MDLMeshBufferZone`](/documentation/ModelIO/MDLMeshBufferZone)

---

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