enum Binding {
SoNormalBinding::OVERALL Whole object has same normal
SoNormalBinding::PER_PART One normal for each part of object
SoNormalBinding::PER_PART_INDEXED One normal for each part, indexed
SoNormalBinding::PER_FACE One normal for each face of object
SoNormalBinding::PER_FACE_INDEXED One normal for each face, indexed
SoNormalBinding::PER_VERTEX One normal for each vertex of object
SoNormalBinding::PER_VERTEX_INDEXED One normal for each vertex, indexed
}