# TerrainHeightmapSyncControl

> Controls what Terrain heightmap data to synchronize when there are changes to the heightmap texture.

## Definition

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

```csharp
public enum TerrainHeightmapSyncControl
```

## Remarks

Additional Resources: [TerrainData.CopyActiveRenderTextureToHeightmap](/engine/6000.3/script-reference/unityengine/terraindata/copyactiverendertexturetoheightmap.md), [TerrainData.DirtyHeightmapRegion](/engine/6000.3/script-reference/unityengine/terraindata/dirtyheightmapregion.md), [TerrainData.SyncHeightmap](/engine/6000.3/script-reference/unityengine/terraindata/syncheightmap.md).

## Fields

| Value                                                                                                   | Description                                                                                                                                                                   |
| ------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [HeightAndLod](/engine/6000.3/script-reference/unityengine/terrainheightmapsynccontrol/heightandlod.md) | Synchronizes height data of the heightmap texture from the GPU back to CPU memory. Then computes LOD data, used for determining the tessellation level, from the height data. |
| [HeightOnly](/engine/6000.3/script-reference/unityengine/terrainheightmapsynccontrol/heightonly.md)     | Synchronizes only height data of the heightmap texture from the GPU back to CPU memory.                                                                                       |
| [None](/engine/6000.3/script-reference/unityengine/terrainheightmapsynccontrol/none.md)                 | Does not synchronize the height data nor the LOD data.                                                                                                                        |