How Render(PdfDocument) tags what it lays out: a structure tree built while the flow is drawn, one element per block and part, in construction order, with the page content of each tied to it by MCID and everything else (page backgrounds, watermarks, headers and footers, table rules and backgrounds, repeated table headers, underlines) marked as artifacts.
public sealed class FlowTagging
ISO 32000-2 §14.8 (tagged PDF), §14.7 (structure tree), §14.8.2.2 (artifacts), §14.8.4 (standard structure types), §14.8.5.7 (table
attributes), §14.9.2 (natural language), §14.3.3 (title). The tree is Document, then a Sect per
StartSection(PageTemplate), then each block's StructureType: paragraphs (P, H1...),
lists (L / LI / Lbl / LBody), tables (Table / THead / TBody / TR / TH /
TD with RowSpan, ColSpan, Scope and Headers), figures with Alt, links (Link with the
annotation's object reference) and inline spans that carry a language. A paragraph with the type Caption next to a figure or a table
becomes that element's caption. A block or part that continues on the next page stays one element.
A structure type that is not standard in the chosen namespace is written in the default namespace and role-mapped (§14.8.6.2) to the type
given with WithRoleMapping(String, String), or else to the type the element would have had (a paragraph to P, an image to
Figure, a list to L, a table to Table, a run to Span or Link). Instances are immutable.
kind:method, kind:property, kind:ctor. Press Esc to clear.DefaultGets the default: no document language or title, the PDF 2.0 namespace, no role mappings.LanguageGets the document's natural language written to the catalog's Lang (a BCP 47 tag), or null to leave the catalog as it is.NamespaceGets the namespace the standard structure types are written in.RoleMapGets the role mappings from non-standard structure types to standard ones.TitleGets the document title written to the metadata (dc:title), with DisplayDocTitle set in the viewer preferences, or null to leave both as they are.WithLanguage(String?)Returns a copy with the document language set.WithNamespace(FlowStructureNamespace)Returns a copy writing the standard structure types in ns.WithRoleMapping(String, String)Returns a copy that role-maps the custom structure type type to standardType.WithTitle(String?)Returns a copy with the document title set.