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# MDLVertexAttributeData

An object that provides convenience access to vertex data for a specific vertex attribute of a mesh.

```
class MDLVertexAttributeData
```

## Overview

You retrieve a vertex attribute data object by calling the [`vertexAttributeData(forAttributeNamed:)`](/documentation/ModelIO/MDLMesh/vertexAttributeData(forAttributeNamed:)) method of a [`MDLMesh`](/documentation/ModelIO/MDLMesh) object, which is shorthand for looking up the the [`MDLMeshBuffer`](/documentation/ModelIO/MDLMeshBuffer) object corresponding to the named attribute and using the [`map()`](/documentation/ModelIO/MDLMeshBuffer/map()) method to gain read-only access to its contents.

## Topics

### Accessing Data for a Vertex Attribute

[`dataStart`](/documentation/ModelIO/MDLVertexAttributeData/dataStart)

The offset, in bytes, from the start of the data to where vertex attribute information begins.

[`stride`](/documentation/ModelIO/MDLVertexAttributeData/stride)

The stride, in bytes, between vertex information for consecutive vertices in the data.

[`format`](/documentation/ModelIO/MDLVertexAttributeData/format)

The format of per-vertex data for the attribute.

## Relationships

### Conforms To

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

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

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

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

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

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

### Inherits From

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

---

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