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Traditional options do not allow for order-independent mixing and this node provides for easy mixing of multiple inputs if needed. You can also chain these nodes together for more complex networks using masking to vary bump maps across surfaces while using a single material assignment.
Nodes that supply a resultNG output can connect to this node, examples include PxrTexture and many procedural patterns. This new NG vector type , expresses the signal's gradient and is more accurate and efficient to compute than traditional bump map techniques.
This tech implements many of the developments in: Surface Gradient-Based Bump Mapping Framework.
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This node is the preferred way to supply bump maps to surfaces, older nodes are less desirable for this effect.
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Input Parameters
Mode
Add - Add the results together, A + B
Over - Puts A over B, a mask is useful here to reveal the layer underneath, A+B(1-a)
Subtract - Subtract the results, A - B
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