This node is the preferred way to supply bump maps to surfaces, older nodes are less desirable for this effect. PxrNormalMap is still useful where you can change orientation. |
This node provides a modern way to bump map.
Traditional options do not allow for order-independent mixing and this node provides for easy mixing of multiple inputs if needed. Bump mapping is an inexpensive way to add small surface details through shading rather than modelling them. 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.
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
Connect your pattern or texture node resultNG connection here.
Mask
A simple grayscale (scalar) pattern or texture channel used to mask where you want this particular layer to take effect. This is especially useful when using the Over mode.
This is how strong you want the bump effect to be for this layer and can be controlled using a scalar input such as a pattern or texture channel.
Sometimes you may see darkening on the surface, possibly at the horizon where the normal may point away from the camera. This control can push these normals back towards the camera to avoid this artifact.
Your surface geometry normals can be overridden by the shading normals this provides, if you want to mix these surface normals in with these, you can do so with this control.