# DontRecalculateBounds

> Indicates that Unity should not recalculate the bounds when you set Mesh data using Mesh.SetSubMesh.

## Definition

* **Type:** Field
* **Namespace:** [UnityEngine.Rendering](/engine/6000.6/script-reference/unityengine/rendering.md)
* **Assembly:** UnityEngine.CoreModule

```csharp
DontRecalculateBounds = 8
```

### Remarks

When you use [Mesh.SetSubMesh](/engine/6000.6/script-reference/unityengine/mesh/setsubmesh.md) to modify a Mesh's data, Unity's default behaviour is to re-calculate the values of the [SubMeshDescriptor.bounds](/engine/6000.6/script-reference/unityengine/rendering/submeshdescriptor/bounds.md), startVertex and [SubMeshDescriptor.vertexCount](/engine/6000.6/script-reference/unityengine/rendering/submeshdescriptor/vertexcount.md) fields from the current vertex and index buffer data.

You can make Unity skip these calculations by using the /MeshUpdateFlags.DontRecalculateBounds/ flag. This can be beneficial to performance, however if you use this flag you must make sure that you pass correct values of the `bounds`, `startVertex` and `vertexCount` fields.

Additional Resources: [Mesh.SetSubMesh](/engine/6000.6/script-reference/unityengine/mesh/setsubmesh.md).