# GetVertexAttributeStream(VertexAttribute)

> Get the vertex buffer stream index of a specific vertex data attribute on this MeshData.

## Definition

* **Type:** Method
* **Namespace:** [UnityEngine](/engine/6000.3/script-reference/unityengine.md)
* **Assembly:** UnityEngine.CoreModule

```csharp
public int GetVertexAttributeStream(VertexAttribute attr)
```

### Parameters

**** (\[VertexAttribute]\(/engine/6000.3/script-reference/unityengine/rendering/vertexattribute)): The vertex data attribute to check for.

### Returns

| Type                                                       | Description                                                     |
| ---------------------------------------------------------- | --------------------------------------------------------------- |
| [int](https://learn.microsoft.com/dotnet/api/system.int32) | Stream index of the data attribute, or -1 if it is not present. |

### Remarks

Meshes usually use a single vertex buffer stream, but it is possible to set up a vertex layout where attributes use different vertex buffers (see [Mesh.MeshData.SetVertexBufferParams](/engine/6000.3/script-reference/unityengine/mesh/meshdata/setvertexbufferparams.md)). When you use such a layout, use this function to query which vertex buffer stream a given attribute is part of.

Note that this function returns the index of the stream, without specifying where the attribute is within the stream. To identify the location of a given attribute in the stream, use [Mesh.MeshData.GetVertexAttributeOffset](/engine/6000.3/script-reference/unityengine/mesh/meshdata/getvertexattributeoffset.md).

Additional Resources: [Mesh.MeshData.GetVertexAttributeOffset](/engine/6000.3/script-reference/unityengine/mesh/meshdata/getvertexattributeoffset.md), [Mesh.MeshData.vertexBufferCount](/engine/6000.3/script-reference/unityengine/mesh/meshdata/vertexbuffercount.md), [Mesh.MeshData.GetVertexBufferStride](/engine/6000.3/script-reference/unityengine/mesh/meshdata/getvertexbufferstride.md), [Mesh.GetVertexAttributeStream](/engine/6000.3/script-reference/unityengine/mesh/getvertexattributestream.md).