createNormalsIfAbsent
An option for automatically generating surface normals if they are absent when loading geometry.
Declaration
static let createNormalsIfAbsent: SCNSceneSource.LoadingOptionDiscussion
The value for this key is an NSNumber object containing a Boolean value. The default value is false.
To participate in lighting and shading, a geometry must include surface normal vectors in its vertex data. Some scene files may not contain such data. If you set this option’s value to true, SceneKit applies heuristics to generate surface normal data for each geometry it loads from the scene source if such data is absent.