# SetDetailLayer

> Sets the detail layer density map.

## Definition

* **Type:** Method
* **Namespace:** [UnityEngine](/engine/7000.0/script-reference/unityengine.md)
* **Assembly:** UnityEngine.TerrainModule

## SetDetailLayer(int, int, int, Int32\[0:,0:])

Sets the detail layer density map.

```csharp
public void SetDetailLayer(int xBase, int yBase, int layer, int[,] details)
```

### Parameters

**** (\[int]\(https\://learn.microsoft.com/dotnet/api/system.int32)): First x index of the detail layer density map to set.**** (\[int]\(https\://learn.microsoft.com/dotnet/api/system.int32)): First y index of the detail layer density map to set.**** (\[int]\(https\://learn.microsoft.com/dotnet/api/system.int32)): The index of the detail in the [TerrainData.detailPrototypes](/engine/7000.0/script-reference/unityengine/terraindata/detailprototypes.md) array.**** (\[int\[,]]\(https\://learn.microsoft.com/dotnet/api/system.int32)): Array of detail object density values indexed as `[y,x]`.

### Remarks

The Terrain system uses detail layer density maps. Each map is essentially a grayscale image where each pixel value specifies the number of detail objects to procedurally place in the terrain area that corresponds to the pixel. These values depend on which [DetailScatterMode](/engine/7000.0/script-reference/unityengine/detailscattermode.md) is set. Because several different detail types may be used, the map is arranged into "layers" - the array indices of the layers are determined by the order of the detail types defined in the Terrain inspector (ie, when the Paint Details tool is selected).

The `details` array must have the dimensions \[height,width] and is indexed as \[y,x].

### Examples

```csharp
using UnityEngine;

public class ExampleClass : MonoBehaviour
{
    // Set all pixels in a detail map below a certain threshold to zero.
    void DetailMapCutoff(Terrain t, float threshold)
    {
        // Get all of layer zero.
        var map = t.terrainData.GetDetailLayer(0, 0, t.terrainData.detailWidth, t.terrainData.detailHeight, 0);

        // For each pixel in the detail map...
        for (int y = 0; y < t.terrainData.detailHeight; y++)
        {
            for (int x = 0; x < t.terrainData.detailWidth; x++)
            {
                // If the pixel value is below the threshold then
                // set it to zero.
                if (map[y, x] < threshold)
                {
                    map[y, x] = 0;
                }
            }
        }

        // Assign the modified map back.
        t.terrainData.SetDetailLayer(0, 0, 0, map);
    }
}
```

## SetDetailLayer(Vector2Int, int, Int32\[0:,0:])

Sets the detail layer density map.

```csharp
public void SetDetailLayer(Vector2Int basePosition, int layer, int[,] details)
```

### Parameters

**** (\[Vector2Int]\(/engine/7000.0/script-reference/unityengine/vector2int)): First index of the detail layer density map to set.**** (\[int]\(https\://learn.microsoft.com/dotnet/api/system.int32)): The index of the detail in the [TerrainData.detailPrototypes](/engine/7000.0/script-reference/unityengine/terraindata/detailprototypes.md) array.**** (\[int\[,]]\(https\://learn.microsoft.com/dotnet/api/system.int32)): Array of detail object density values indexed as `[y,x]`.

### Remarks

The Terrain system uses detail layer density maps. Each map is a grayscale image where each pixel value specifies the number of detail objects to procedurally place in the terrain area that corresponds to the pixel. These values depend on which [DetailScatterMode](/engine/7000.0/script-reference/unityengine/detailscattermode.md) is set. Because several different detail types can be used, the map is arranged into layers. The array indices of the layers are determined by the order of the detail types defined in the Terrain Inspector when the Paint Details tool is selected.

The `details` array must have the dimensions `[height,width]` and is indexed as `[y,x]`.