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# In

Outputs areas of foreground that overlap with the alpha of background.

## Parameter Types

|Input       |Type         |
        |------------|-------------|
        |`Foreground`|Color4<Float>|
        |`Background`|Color4<Float>|
        |`Mix`       |Float        |

|Output|Type         |
        |------|-------------|
        |`Out` |Color4<Float>|

## Parameter descriptions

- `Foreground`: The `color4` foreground input. `F` represents the RGB component of this parameter. `f` represents the alpha component of this parameter.
- `Background`: The `color4` background input. `B` represents the RGB component of this parameter. `b`represents the alpha component of this parameter.
- `Mix`: The weight of the blend operation. The higher the value of `Mix`, the more apparent the effect of the blend operation. The default value is `1`. Values outside of the range `0-1` produce an undefined effect outside of the node’s intended function.

## Discussion

The in node determines its output using the alpha channels of the foreground and background inputs. The RGB component of the output is `F*b` and the alpha component of the output is `f*b`.
Visually this means that within the output, the foreground values that overlap with the background alpha are preserved.
Below is a simple node graph that uses the In node to blend a tile and rock texture.

![](images/ShaderGraph-Docs/InGraph~dark.png)

Below are the two original images, the image representation of the alpha of the background, and the resulting blended texture applied to a cube.



![](images/ShaderGraph-Docs/DisjointOverMaterial1.png)



![](images/ShaderGraph-Docs/DisjointOverMaterial2~dark.png)



![](images/ShaderGraph-Docs/InMaterialAlpha.png)

![](images/ShaderGraph-Docs/InMaterial.png)

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