public static void AddAnnotationReference(SceneElement element, AnnotationSceneNode annotation)
{
ExceptionChecks.CheckNullArgument <SceneElement>(element, "element");
ExceptionChecks.CheckNullArgument <AnnotationSceneNode>(annotation, "annotation");
string str = annotation.Id;
if (string.IsNullOrEmpty(str))
{
str = AnnotationUtils.SetAnnotationId(annotation);
}
IEnumerable <string> referencedAnnotationIds = AnnotationUtils.GetReferencedAnnotationIds(element);
AnnotationUtils.SetAnnotationReferences(element, EnumerableExtensions.AppendItem <string>(referencedAnnotationIds, str));
}