NormalInterpolator generates a series of normal (perpendicular) 3-tuple SFVec3f values. Each vector value has unit length, i.e. the set of allowed vectors describes the surface of a unit sphere. Authors can ROUTE value_changed output events to a Normal node's vector field, or to another 3-tuple SFVec3f field.

X3D Tooltips of interest: NormalInterpolator.

X3D Specification sections of interest: 19 Interpolation component, 19.2 Concepts and 19.4.5 NormalInterpolator.

X3D Examples Archives of related interest:

• VRML 2 Sourcebook:  Chapter 19 Normals Shading, Figure 19 27 Square Face Animating Normals
• X3D for Web Authors: Chapter 07 Event Animation Interpolation

This viewpoint slideshow is online at
https://www.web3d.org/x3d/content/examples/ConformanceNist/Interpolators/NormalInterpolator/viewpointSlideshow.html

Viewpoint image version history at
https://sourceforge.net/p/x3d/code/HEAD/tree/www.web3d.org/x3d/content/examples/ConformanceNist/Interpolators/NormalInterpolator/_viewpoints