EXAMPLE (click to run): The following example illustrates three typical uses of the Normal node (see Figure 3-39). The first IndexedFaceSet defines a Normal node that has five normals and uses the normalIndex field to assign the correct normal to the corresponding vertex of each face. The second IndexedFaceSet defaults to using the coordIndex field to index into the Normal node. This is probably the most common use of the Normal node (i.e., one normal for each coordinate). The third IndexedFaceSet applies a Normal node to the faces of the geometry. This produces a faceted polygonal object and may render faster than when specifying normals per vertex:

#VRML V2.0 utf8
Group { children [
  Transform {
    translation -3 0 0
    children Shape {
      appearance DEF A1 Appearance {
        material Material { diffuseColor 1 1 1 }
      }
      geometry IndexedFaceSet {
        coord DEF C1 Coordinate {
          point [ 1 0 1, 1 0 -1, -1 0 -1, -1 0 1, 0 3 0 ]
        }
        coordIndex [ 0 1 4 -1  1 2 4 -1  2 3 4 -1  3 0 4 ]
        normal Normal {
          vector [ .707 0  .707, .707 0 -.707, -.707 0 -.707,
                   -.707 0  .707, .707 .707 0, 0 .707 -.707,
                   -.707 .707 0, 0 .707 .707 ]
        }
        normalIndex [ 0 1 4 -1  1 2 5 -1  2 3 6 -1  3 0 7 ]
      }
    }
  }
  Transform {
    children Shape {
      appearance USE A1
      geometry IndexedFaceSet {
        coord USE C1
        coordIndex [ 0 1 4 -1,  1 2 4 -1,  2 3 4 -1,  3 0 4 ]
        normal Normal {     # use coordIndex for normal indices
          vector [ .707 0  .707,  .707 0 -.707,
                  -.707 0 -.707, -.707 0  .707, 0 1 0 ]
        }
      }
    }
  }
  Transform {
    translation 3 0 0
    children Shape {
      appearance USE A1
      geometry IndexedFaceSet {
        coord USE C1
        coordIndex [ 0 1 4 -1,  1 2 4 -1,  2 3 4 -1,  3 0 4 ]
        normal Normal {
          vector [ .707 .707 0, 0 .707 -.707, -.707 .707 0,
                      0 .707 .707 ]
        }
        normalIndex [ 0, 1, 2, 3 ]
        normalPerVertex FALSE
      }
    }
  }
  DirectionalLight { direction 1 0 0 }
  Background { skyColor 1 1 1 }
] }