Vyuh Document

Layout ​

vyuh_document

dart
import 'package:vyuh_document/layout.dart';
// also re-exported by package:vyuh_document_editor/document_editor_rendering.dart

Layout resolves a document revision into immutable geometry: pages, fragments, lines, carets and hit regions. Paint, hit testing, carets, PDF and print all read that one snapshot. Layout is pure Dart; text measurement comes in through a port the editor implements with Flutter.

The layout pipeline One document revision is measured through the DocumentMeasurementPort into block line metrics; the editor supplies FlutterDocumentMeasurementPort for text shaping. Measured blocks are paginated into a PaginatedLayout of pages, columns and notes. ResolvedLayoutBuilder and each element's layout adapter resolve that into one immutable ResolvedDocumentLayout. Paint, hit testing, carets and selection, PDF export and print all read that same geometry. Text shaping FlutterDocumentMeasurementPort editor supplies Document one revision 1 Measure DocumentMeasurementPort BlockLineMetrics 2 Paginate PaginatedLayout pages · columns · notes 3 Resolve ResolvedLayoutBuilder element layout adapters ResolvedDocumentLayout pages · fragments · lines · carets · hit regions immutable, keyed to one content revision Painteditor canvas Hit testingpointer hits Caretsselection PDFexport Printsame pages no consumer measures again
From document to resolved pages

Core contracts ​

TypePurpose
ResolvedDocumentLayoutThe immutable geometry of one content revision
DocumentLayoutGenerationA layout bound to a document snapshot; ownsCanonicalSnapshot(...), materializeCompleteDocument(...) (used by export)
DocumentLayoutSession, ContinuousDocumentLayoutSessionPaged and pageless layout sessions
DocumentMeasurementPortThe text measurement seam (the editor supplies FlutterDocumentMeasurementPort)
ResolvedBlockLayoutAdapter, ResolvedBlockLayoutAdapterRegistryHow an element contributes its geometry

Pages and fragments ​

TypePurpose
ResolvedPageFragment, ResolvedBlockFragment, ResolvedContainerFragmentPlaced content
ResolvedPageRegionFragment, ResolvedPageRegionTemplateHeaders and footers per page
ResolvedPageFootnoteBand, ResolvedPageEndnoteBandNote areas
ResolvedFragmentIndexCatalogFragment lookup by page (indexesForPage)
ResolvedFloatingBlockGeometryFloating objects

Interaction geometry ​

TypePurpose
ResolvedHitRegion, ResolvedPageHitIndexPointer hit testing
ResolvedCaretBox, ResolvedCaretOccurrence, ResolvedCaretLineIndexCarets and line navigation
ResolvedPageTextIndexText positions on pages

Generated graphics ​

ResolvedGeneratedGraphicScene, ResolvedGeneratedGraphicLayoutAdapter and ResolvedGeneratedGraphicPaintArtifact carry Mermaid, KaTeX and diagram scenes from their element packages to every painter.

Integration ​

layout_integration.dart exposes frozen geometry storage and the occurrence catalog to sibling packages.