Houdini 22.0 Nodes Compositing nodes
Overlays 2 normal maps together
This node adds 2 normal maps together.
You are able to dive into this node and see inside the copfilter what formula we are using for adding the 2 maps together.
The general idea is that we move both normal maps into -1 to 1 space, add them together, normalize the result, and move things back to 0-1 space.
Note
Replaced by 
Combine Normals COP in Copernicus.
Imports geometry attributes as image planes using a UV attribute
Generates a blackbody ramp, or colorizes a black and white image with a blackbody ramp
Converts a single mosaic (flipbook/subuv) image into a sequence of sub images based on the frame
Generates a texture that can be used as a simple resolution checkerboard
Simple Helper Node to generate the default Normal Color
Overlays 2 normal maps together
Convert a grayscale image into a normal map
Invert individual channels on an image
Adjusts black point, white point, and midrange to increase, balance, or decrease contrast on a Normal Map.
Rotates a normal map while correcting recalculating it’s internal vectors
Ensures the normal map is balanced in a unit vector
Load Substance Archive (SBSAR) Files into COPs