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Computes the facing ratio of the geometry: a simple dot product between the camera vector or direction and the surface normal. Note that some scene entities do not have a defined normal, like volumes.

Input Parameters

Use

Choose the rendering camera direction or a predefined direction

Direction

Supply a direction vector when not using the camera direction

Coordinate System

Supply a useful coordinate system, object, world, camera, or other defined space.

Face Forward

The facing ratio can be negative if the normal is pointing away from the camera. This will flip the normal to always give a positive result.

Clamp

Clamp the result from 0 to 1

Invert

Inverts the facing ratio: black becomes white and vice-versa.

Mode

Choose between specifying an Ior or Gamma

Ior

When using the Ior mode set above, choose an index of refraction value, typically 1.0 to 3.0, useful for simulating a dielectric surface.

Gamma

When using the gamma node set above, a simple gamma function to shape the facing ratio. A value of 1.0 is neutral

Bump Normal

If the surface is bump-mapped, input the bump normal here. If not connected, the node will use this shading normal.

Output Parameters

resultF

The single-component (float) value produced by the facing ratio computation.