PdfOptionalContent
Optional Content metadata (ISO 32000-1 §8.11). Optional Content Groups (OCGs) are the PDF spec's name for "layers": chunks of content that can be selectively shown or hidden via /OC marked-content sections and Form XObjects with /OC entries.
This view exposes the OCG topology and default visibility state (read-only). The renderer honours /OC visibility: marked-content sections and XObjects whose OCG is hidden in the default configuration are skipped while drawing.
Types
One Optional Content Group. The id is the OCG's PDF object number stringified. It is stable inside the document, and /OC marked-content sections refer to it.
Properties
Display name of the default config (/D /Name), if present.
All OCGs declared in /OCProperties /OCGs.
Identifiers of OCGs that are explicitly OFF in the default configuration.
Identifiers of OCGs that are ON in the default configuration.