/* Public domain */ __BEGIN_DECLS M_Plane M_PlaneFromPts(M_Vector3, M_Vector3, M_Vector3); M_Plane M_PlaneRead(AG_DataSource *_Nonnull); void M_PlaneWrite(AG_DataSource *_Nonnull, M_Plane *_Nonnull); M_Real M_PlaneVectorAngle(M_Plane, M_Vector3); __END_DECLS