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Specifies the type of mapping desired – Bump Map, Normal Map or Displacement Map. In the case of a Normal Map, a color is expected in as a value, it can be encoded in the style or DirectX or OpenGL. In case of Bump Map or Displacement Map the shader will only consider the R value. Displacement maps can be interpreted as as having their center value (the one that produces no effect) at 0.0 or 0.5.
Value
A colour input specifying bump direction (Normal Map) or intensity (Bump Map / Displacement Map).
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