Public API Surface

The supported surface is the NwcIO and NwcIO.Model.* namespaces listed here. The NwcIO.Internal.* types (chunk decoders, byte streamers, container reader/writer, JSON/GLB/OBJ/IFC exporters) are also compiled as public — the tests and the CLI consume them directly — but they are implementation details: they are not covered by compatibility guarantees and may change in any release. Making them internal is tracked separately (#103).

Core Document & Hierarchy (NwcIO, NwcIO.Model)

Type	Description
NwcDocument	Primary document container holding the root scene graph node, meshes, materials, viewpoints, selection sets, and TimeLiner schedules. Opens .nwc, .nwd, and .nwf files via NwcDocument.Open.
NwcDocumentBuilder	Fluent builder API for creating Navisworks documents and geometry programmatically from code.
NwcWriter	Direct #LcUStream-V1.1 binary container serializer and continuous zlib chunk writer.
NwcReaderOptions	Per-open options: which streams to read (meshes, materials, viewpoints, selection sets, TimeLiner), catalog retention.
NwcAssembly	Federated multi-model assembly: Create, LoadFromDirectory, OpenNwf (with UnresolvedXRefs/SkippedXRefs reporting), combined meshes/materials/bounds, per-assembly exports and clash runs.
NwcNode	Scene graph tree node representing layers, categories, composite elements, and geometry instances with hierarchical transformations and properties.
NwcPropertyRecord	Property key-value record (class, name, string value, tags) as parsed from Navisworks property streams.
NwcMesh & NwcMaterial	Triangle mesh with vertices, indices, world-space transform, bounding box, and PBR material.
NwcTransform	Parsed pose/transform records with quaternion rotation and affine 4×4 matrix conversion.
NwcFileInfo	Source path, loader plugin, and export timestamp from the partition header.
NwcXRef & NwcXRefTable	External references with suffix-based resolution (TryResolve, Exists) and the parsed XRef table.
NwcCamera, NwcSavedViewpoint, NwcCameraProjection	Camera model (position, unit rotation quaternion, computed direction/up/target) and saved viewpoints.
Vector3d, Quaterniond, BoundingBox3d, RgbaColor	Double-precision geometry primitives and RGBA colour.
NwcClash	Simple pairwise clash check between two meshes.

Coordination & Clash Detection (NwcIO.Model.Clash)

Type	Description
NwcClashDetector	Broad-phase BVH and narrow-phase 3D triangle-to-triangle collision engine (Run over a document or federated assembly, driven by an NwcClashTest).
NwcClashTest, NwcClashSelection, NwcClashResult, NwcClashObject	Clash test definition (type, tolerance, per-side selections), results, and the involved elements.
NwcClashBatch, NwcClashRule, NwcClashComment	Batch test container, filtering rules (ignore thresholds, custom predicates), and review comments.
NwcClashGroup	Grouped clash clusters produced by NwcClashGrouper.
NwcClashGrouper	Automated clustering of clashes by proximity, element, grid line, or layer.
NwcClashMatrix, NwcClashDiscipline, NwcClashMatrixCell	\(N \times M\) multi-discipline coordination matrix with per-cell tolerance/type, automated execution, Markdown generation, and BCF 2.1 export.
NwcClashBcfExporter	buildingSMART BCF 2.1 export of clash tests and results.
NwcXmlClashSerializer	Roundtrip Navisworks Clash Report XML (nw-clashreport-11.0.xsd) reader and writer.
NwcNwfManifest	Federation manifest used by NwcAssembly tooling.

4D TimeLiner, Selection Sets & Appearance (NwcIO.Model.TimeLiner, .Sets, .Appearance)

Type	Description
NwcTimeLinerSchedule & NwcTimeLinerTask	WBS task hierarchy, planned/actual dates, costs, progress, and simulation queries.
NwcTimeLinerXmlSerializer	Full roundtrip serialization of Navisworks TimeLiner Exchange XML.
NwcTimeLinerMsProjectXmlSerializer	Microsoft Project XML schedule import/export.
NwcTimeLinerPrimaveraXerSerializer	Primavera P6 XER schedule import/export.
NwcTimeLinerCsvSerializer	CSV schedule export.
NwcTimeLinerLinker	Rule-based automated linking of schedule tasks to geometry.
NwcSelectionSet, NwcSearchSet, NwcSelectionSetFolder, NwcSetItem	Manual selection sets, dynamic query search sets, and set folders.
NwcSearchCondition & NwcSearchOperator	Search criteria over node built-ins and property records (equals, contains, wildcard, comparisons).
NwcXmlSetSerializer	Navisworks selection-set XML exchange.
NwcQuickProperties	Curated quick-properties view over property records.
NwcAppearanceProfiler, NwcAppearanceRule, NwcXmlAppearanceProfilerSerializer	Rule-based colouring by search conditions and its XML exchange format.

3D Geometry & Spatial Analysis (NwcIO.Model.Grids, .Measure, .Diff, .Spatial, .Sectioning, .Redline)

Type	Description
NwcGridSystem, NwcGridLine, NwcGridIntersection	Building grid lines and axes with 2D/3D intersection calculations and spatial clash labelling.
NwcMeasureEngine	Double-precision 3D point-to-point, point-to-mesh and mesh-to-mesh distance, clearance, and area/volume calculations.
NwcDiffEngine (with NwcDiffReport, NwcDiffOptions, NwcElementDiff)	Revision comparison and differential geometry/property analysis.
NwcSpatialIndex	SAH bounding-volume hierarchy for raycasts and accelerated proximity queries (RaycastHit).
NwcSectionPlane, NwcSectionBox, NwcSectionAlignment, NwcMeshClipper	Section planes and six-sided section boxes with mesh clipping.
NwcXmlViewpointSerializer, NwcViewpointBcfExporter	Navisworks viewpoint XML exchange and BCF viewpoint export.
NwcRedline* (NwcRedline, Arrow, Cloud, Ellipse, Line, Tag, Text, NwcRedlineStatus)	Redline annotation records.

Export (NwcIO, NwcIO.Model.Viewer)

Type	Description
NwcDocument.SaveIfc / NwcAssembly.SaveIfc	ISO 10303-21 STEP export supporting IFC2x3 Coordination View and modern IFC4 mesh tessellation (IfcTriangulatedFaceSet), configured via NwcIfcExportOptions (NwcIfcSchemaVersion, NwcIfcLengthUnit).
NwcDocument.SaveGlb / SaveObj, NwcAssembly.SaveGlb / SaveObj	Binary glTF 2.0 and Wavefront OBJ geometry export entry points.
NwcDocument.SaveHtmlViewer / NwcAssembly.SaveHtmlViewer	Interactive single-file 3D WebGL viewer exporter with 4D schedule playback (NwcHtmlViewerExporter, NwcHtmlViewerOptions).
NwcJsonExportOptions	Indentation and content toggles for JSON export (NwcDocument and the CLI).
GlbExporter & ObjExporter (NwcIO.Internal.Export)	Low-level public static exporters the Save* entry points delegate to; implementation surface, not covered by compatibility guarantees.

Container & Parsing (NwcIO.Internal.* — public but unsupported)

Type	Description
NwcContainerReader / NwcContainerWriter	#LcUStream-V1.1 section/chunk reader and writer.
NwcContainer, LcRawStream, LcUStreamHeader, NwcStreamKind	Decompressed stream records and their best-effort classification.
StreamClassifier, PartitionHeaderParser, PropertyRecordScanner, SceneTreeBuilder, GuidTableParser, TransformParser, MeshParser, MaterialParser, DbCacheParser, XRefTableParser	Stream classifiers and format decoders.
JsonExporter	Low-level JSON export helper. (The IFC and clash-report exporters are internal.)