Description

The Blend (Normal) node allows you to perform a blend between two normal map texture inputs using one of the available blend modes. Normal map blend modes are different from those used for color or grayscale maps. For a full list of blend modes available specifically in the Blend (Normal) node, see the Normal map blend modes reference.

The node blends the content of the Foreground input on top of the Background input. You can constrain the blend effect to a specific area by using an optional grayscale Mask input.

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1. Ensure that the textures you want to blend are already in your Node Graph. You can extract the normal map from any material (provided it exists in the material) using the Split Material node.
2. For normal maps imported via the Asset Library, ensure that the PBR Type of the import is set to Normal when you first move that asset into the Node Graph.
3. Create a new Blend (Normal) node on the graph. It can be found under the Composition category in the Node Library.
4. Connect the normal map you wish to use as the Foreground into the corresponding input port, and the other normal map into the Background port.
5. (Optional) Connect a grayscale mask into the Mask input port if you wish to constrain the blend effect to a specific area. In this mask, white represents areas of the normal map where you want blending to occur. You can create this mask using the Mask Paint node, the Gradient node, or from a custom imported asset.
6. Choose your desired Blend Mode, which determines how the node blends the normal map together. To learn more about blend modes available in the Blend (Normal) node, see the Normal map blend modes reference[link].
7. View the blending results by bringing the Blend (Normal) node into the 2D and/or 3D Viewports.

The output (right) of combining the background input (left) with another normal map, using a mask (middle) to constrain the blending to one area.

Node Reference

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