UE4 – Material Fresnel Node

Software:
Unreal Engine 4.18

The UE4 Fresnel node is actually a “Facing Ratio” node (aka Perpendicular / Parallel) with some extra control.
It basically allows controlling material effects according to the incident angle the surface is viewed at, which is a hugely important feature for designing advanced material effects.

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Exponent:
The steepness of the value / angle curve.

Base Reflect Fraction:
The value at perpendicular angle.

Normal:
An option to connect World Space surface normals input to affect the output of the Fresnel node.
* Tangent Space normals must be converted to World Space by using a Transform Vector node.

Note:
A value of 1.0 for the Exponent parameter, and a value of 0.0 for the Base Reflect Fraction will produce a linear “Facing Ratio” (“Perpendicular / Parallel”) falloff blend.

Examples of different values:
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More info:
https://docs.unrealengine.com/latest/INT/Engine/Rendering/Materials/HowTo/Fresnel/

Related posts:

  1. UE4 – basic architectural glazing material
  2. Understanding Fresnel reflections