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Compatibility matrix

What rvt-rs can and cannot do today, grouped by Revit release, file type, decoded element class, and IFC4 export detail. Every row here is checked against current source code. If a claim in this file disagrees with the source, the source wins and this file is wrong. For the shorter user-facing status summary, see docs/status.md.

Scope sources:

1. Format versions supported

Integration corpus: Autodesk's public rac_basic_sample_family RFA, one file per Revit release 2016 through 2026, exercised by tests/samples.rs via ALL_YEARS = [2016..=2026] in tests/common/mod.rs.

Revit release BasicFileInfo year Partitions/NN marker OLE + schema + metadata Schema-directed walker (ADocument)
2016 2016 Partitions/58 full partial
2017 2017 Partitions/60 full partial
2018 2018 Partitions/61 full partial
2019 2019 Partitions/62 full partial
2020 2020 Partitions/63 full partial
2021 2021 Partitions/64 full partial
2022 2022 Partitions/65 full partial
2023 2023 Partitions/66 full partial
2024 2024 Partitions/67 full full
2025 2025 Partitions/68 full full
2026 2026 Partitions/69 full full

Column definitions:

  • OLE + schema + metadata: opens the CFB container, reads all 13 invariant streams, decompresses Formats/Latest, parses the full class schema (395 classes on the 2024 sample, 13,570 fields at 100% type classification across the 11-release corpus), extracts BasicFileInfo (version / build / GUID / path / locale), parses PartAtom XML, extracts the RevitPreview4.0 PNG thumbnail, decodes Contents, and decodes the 167-byte Global/PartitionTable invariant. This row is full for every supported release.
  • Schema-directed walker: walker::read_adocument locates the ADocument entry point in Global/Latest and walks all declared fields. Reliable on Revit 2024–2026. Returns Ok(None) on 2016–2023 when the entry-point detector can't find a high-confidence offset (see walker.rs §366–370 and docs/rvt-phase4c-session-2026-04-19.md). This is also the bridge the Layer-5b per-class decoders depend on at runtime against real files.

Before 2016 and after 2026: unverified. The schema parser and compression path are likely to still work on near-future releases because the truncated-gzip and Formats/Latest framing have not changed in a decade, but no corpus entry exists outside [2016, 2026], so nothing is claimed.

2. File type support

All four extensions share the same Microsoft Compound File Binary container, the same stream layout, and the same schema. RevitFile::open dispatches purely on the CFB magic D0 CF 11 E0 A1 B1 1A E1, not on the extension, so the same code path handles all four.

Type Extension Read IFC4 export
Project .rvt yes partial: spatial tree/diagnostics; typed elements depend on decoded coverage
Family .rfa yes partial: same pipeline
Project template .rte yes partial: same pipeline
Family template .rft yes partial: same pipeline

Notes:

  • The entire 11-release reference corpus is .rfa (family) files. .rvt / .rte / .rft read the same OLE container and are handled by the same code, but the corpus does not yet include project or template fixtures, so nothing is claimed about .rvt-specific streams that do not appear in families (worksharing metadata, linked-model tables, transmission data beyond the already-decoded TransmissionData).
  • The CLI binaries (rvt-info, rvt-analyze, rvt-schema, rvt-history, rvt-diff, rvt-corpus, rvt-dump, rvt-doc, rvt-ifc) accept any of the four extensions without special-casing.

3. Element class decode coverage

80 decoder structs are registered today. Counted directly from src/elements/mod.rs all_decoders() — the walker dispatch table built at runtime. Grouped by domain below.

Each decoder takes schema-directed instance bytes (from walker::decode_instance) and projects them into a typed Rust struct. Decoders are validated on synthesized schema+bytes fixtures; real-file corpus validation is tracked as Q-01 in the recon report.

Structural (7)

Architectural — host + opening (13)

Architectural — circulation + zoning (7)

Furnishings + generic (6)

Datum + site + levels (6)

Styling (4)

Project organization (7)

Drafting + views (5)

  • View, Sheet, Schedule, ScheduleView (drafting.rs)
  • (ReferencePlane is counted under Structural above because its primary consumer is layout, not drafting views.)

Annotations (4)

  • Dimension, Tag, TextNote, Annotation (annotations.rs)
  • Dimensions include linear / angular / radial / arc-length subtypes via the DimensionKind discriminator projected from the schema; tag orientation and horizontal alignment enums are exposed on TagOrientation and HorizontalAlignment.

Parameters and value carriers (10)

  • ParameterElement, SharedParameter (parameters.rs)
  • Both expose the StorageType enum (None, Integer, Double, String, ElementId, Other) so callers can route parameter values into property-set emission (see §4 IFC-31).
  • AProperty, APropertyBoolean, APropertyInteger, APropertyEnum, APropertyDouble1, APropertyDouble3, APropertyFloat, APropertyFloat3 (parameters.rs)
  • These value-carrier decoders are building blocks for parameter extraction. Real-file parameter recovery still depends on the object-graph and partition-record linkage described in docs/status.md.

MEP — mechanical / electrical / plumbing (11)

  • Electrical: ElectricalEquipment, ElectricalFixture, LightingFixture, LightingDevice (mep.rs)
  • Mechanical: Duct, DuctFitting, MechanicalEquipment (mep.rs)
  • Plumbing: Pipe, PipeFitting, PlumbingFixture (mep.rs)
  • Generic MEP: SpecialtyEquipment (mep.rs)
  • All MEP instances project onto a shared MepInstance typed view with an optional MepSystemClassification (Supply / Return / Exhaust / …) so IFC distribution-system emission (IFC-10, future) can key off it without re-reading the schema.

Group sum: 7 + 13 + 7 + 6 + 6 + 4 + 7 + 5 + 4 + 10 + 11 = 80, matching all_decoders().len().

4. IFC4 export coverage

The bridge ifc::build_ifc_model maps each decoded element to an IfcEntity::BuildingElement, and ifc::write_step serialises the model as an IFC4 STEP file. A fixed spatial hierarchy (IfcProject → IfcSite → IfcBuilding → IfcBuildingStorey) always ships; per-element shape / material / property-set emission is per-class.

Column definitions:

  • IFC entity + placement: a valid IfcWall / IfcSlab / … is constructed and wired to the storey via IfcRelContainedInSpatialStructure. Always yes for every Revit class that has a mapping in category_map.rs; unknown classes fall back to IfcBuildingElementProxy rather than being dropped.
  • Extruded geometry: an IfcRectangleProfileDef + IfcExtrudedAreaSolid + IfcShapeRepresentation + IfcProductDefinitionShape chain is emitted and attached to the element's Representation slot, iff the caller supplies an Extrusion via one of the helpers in from_decoded.rs (wall_extrusion, slab_extrusion, roof_extrusion, ceiling_extrusion, column_extrusion). The helpers exist for the classes marked "yes"; they do not exist yet for the classes marked "no helper".
  • Material association: an IfcMaterial + IfcRelAssociatesMaterial is emitted iff the caller populates BuilderOptions.materials (see materials_from_revit) and sets ElementInput.material_index. For compound hosts, ElementInput.material_layer_set_index routes through an IfcMaterialLayerSet + IfcMaterialLayerSetUsage chain (IFC-28 / IFC-29); for profile-driven members, material_profile_set_index routes through IfcMaterialProfileSet + IfcMaterialProfileSetUsage (IFC-30). Precedence order is profile_set > layer_set > single material — whichever is set wins.
  • Property set: an IfcPropertySet + IfcPropertySingleValue + IfcRelDefinesByProperties (IFC-31 / IFC-33) is emitted iff the caller supplies a PropertySet via a dedicated helper (wall_property_set, door_property_set, window_property_set, stair_property_set exist today). Quantity-typed properties route through IfcQuantityArea / IfcQuantityVolume / IfcQuantityCount / IfcQuantityTime / IfcQuantityWeight (IFC-32), with Imperial-to-SI conversion done at emission time (square-feet → m², cubic-feet → m³, pounds → kg).
  • Opening / fill: for doors / windows, iff the caller sets host_element_index and extrusion on the opening, the writer emits IfcOpeningElement + IfcRelVoidsElement (host → opening, IFC-37) + IfcRelFillsElement (opening → door/window, IFC-38).
Revit class IFC entity Placement + storey Extrusion helper Material assoc Property set Opening / fill
Level IfcBuildingStorey built-in n/a n/a n/a n/a
Grid IfcGrid yes no helper n/a n/a n/a
Wall IfcWall (STANDARD) yes yes (wall_extrusion) yes yes (wall_property_set) n/a
CurtainWall IfcCurtainWall yes no helper no helper no helper n/a
Door IfcDoor yes caller-supplied yes yes (door_property_set) yes
Window IfcWindow yes caller-supplied yes yes (window_property_set) yes
Floor IfcSlab (FLOOR) yes yes (slab_extrusion) yes no helper n/a
Roof IfcRoof yes yes (roof_extrusion) yes no helper n/a
Ceiling IfcCovering (CEILING) yes yes (ceiling_extrusion) yes no helper n/a
Stair IfcStair yes no helper yes yes (stair_property_set) n/a
Railing IfcRailing yes no helper yes no helper n/a
Ramp IfcRamp yes no helper yes no helper n/a
Column IfcColumn (COLUMN) yes yes (column_extrusion) yes no helper n/a
StructuralColumn IfcColumn (COLUMN) yes yes (column_extrusion) yes no helper n/a
StructuralFraming IfcBeam (BEAM) yes no helper yes no helper n/a
StructuralFoundation IfcFooting yes no helper yes no helper n/a
Rebar IfcReinforcingBar yes no helper yes no helper n/a
Room IfcSpace (INTERNAL) yes no helper n/a no helper n/a
Area IfcSpace yes no helper n/a no helper n/a
Space IfcSpace yes no helper n/a no helper n/a
Furniture IfcFurniture yes no helper yes no helper n/a
FurnitureSystem IfcFurniture (USERDEFINED) yes no helper yes no helper n/a
Casework IfcFurniture yes no helper yes no helper n/a
LightingFixture IfcLightFixture yes no helper yes no helper n/a
LightingDevice IfcLightFixture (USERDEFINED) yes no helper yes no helper n/a
ElectricalEquipment IfcElectricAppliance yes no helper yes no helper n/a
ElectricalFixture IfcLightFixture yes no helper yes no helper n/a
MechanicalEquipment IfcFlowController yes no helper yes no helper n/a
Duct IfcDuctSegment yes no helper yes no helper n/a
DuctFitting IfcDuctFitting yes no helper yes no helper n/a
Pipe IfcPipeSegment yes no helper yes no helper n/a
PipeFitting IfcPipeFitting yes no helper yes no helper n/a
PlumbingFixture IfcSanitaryTerminal yes no helper yes no helper n/a
SpecialtyEquipment IfcBuildingElementProxy (USERDEFINED) yes no helper yes no helper n/a
Mass IfcBuildingElementProxy (USERDEFINED) yes no helper n/a no helper n/a
GenericModel IfcBuildingElementProxy yes no helper n/a no helper n/a
(unknown class) IfcBuildingElementProxy yes n/a n/a n/a n/a

Notes:

  • "Yes (mapped; decoder pending)" rows: the class has a category-map entry and would round-trip through the bridge if a decoder existed, but no ElementDecoder for the class is registered in all_decoders() today, so the bridge never sees a decoded instance to map. See §3 MEP note.
  • The units slot is populated via BuilderOptions.units (typically from RvtDocExporter::build_unit_list) and emits as IfcUnitAssignment. Classifications (OmniClass / Uniformat from PartAtom) emit as IfcClassification + IfcClassificationReference.
  • The STEP writer is deterministic under write_step_with_options(model, StepOptions { timestamp }) — a fixed timestamp produces byte-identical output across runs. Unicode escaping is ISO-10303-21-correct (BMP \X2\HHHH\X0\, supplementary \X4\HHHHHHHH\X0\, backslash doubled, control chars \X\HH).
  • A committed sample IFC output lives at tests/fixtures/synthetic-project.ifc and is exercised by tests/ifc_synthetic_project.rs. It opens cleanly in BlenderBIM / IfcOpenShell spatial browsers.

5. Known limitations

  • No semantic write path for Revit files. Stream-level patching (writer::write_with_patches) can replace the bytes of a named stream, re-compress with truncated gzip, and re-embed into a byte-preserving sibling file (13/13 streams identical on the 2024 sample round-trip). Field-level semantic writes (edit a specific Wall's unconnected height and round-trip back to a Revit-openable .rvt) are not implemented.
  • No format versions before Revit 2016. Earlier Revit releases used a different compression + schema framing that this library has not been probed against. No claim is made about 2015-or-earlier.
  • No IFC2X3 or IFC4.3 export. The STEP writer targets IFC4 only. The category map is structured to make a future IFC2X3 / IFC4.3 swap a table replacement, but it has not been swapped.
  • No encrypted or password-protected files. Revit's "Protected" models use a wrapper format this library does not attempt to strip. CFB open will succeed on the outer container but inner streams will be gibberish.
  • No linked-model resolution. .rvt projects can carry references to external .rvt / .rfa / .rcp / .dwg / .ifc files; this library reads the host file's CFB streams but does not follow or resolve links. Any linked-model metadata is exposed only as raw bytes on whichever stream carries it (TransmissionData on project files).
  • MEP geometry extraction. The 11 MEP classes listed in §3 decode their schema metadata (class, name, family-instance linkage, system classification), but the geometric centerline / 3D path of ducts, pipes, conduits, and cable-trays is not yet extracted — the IFC rows above ship an IfcDuctSegment / IfcPipeSegment with placement and spatial-containment but no IfcShapeRepresentation. Routing-path recovery is tracked as a Phase-5 extension once the curve-graph decoder lands.
  • Annotation geometry. The 4 annotation classes (Dimension, Tag, TextNote, Annotation) decode the annotation-element data (anchor points, text contents, orientation, witness-line references) but do not yet render 2D annotation graphics into IFC presentation layers. Drawn sheets therefore export as IfcAnnotation shells without the witness-line / leader / dimension-string geometry that a plotted sheet would need.
  • Schema-directed walker is partial on 2016–2023. See §1. The stream layout and entry-point heuristics differ pre-2024; read_adocument returns Ok(None) when it can't find a high-confidence offset instead of returning possibly-wrong fields.
  • Geometry extraction is Phase 5. The IFC export produces valid placement and extruded rectangular solids when the caller supplies dimensions. The reader now recovers rough rectangular swept solids for the Revit 2023 Einhoven ArcWall record layout, but arbitrary wall layouts, 2024+ ArcWall records, floors, doors, windows, profile shapes, and brep geometry are still pending. The Extrusion helpers in from_decoded.rs remain the general bridge for caller-supplied dimensions.
  • Parcel of unparsed streams. Global/DocumentIncrementTable, Global/History, Global/ContentDocuments, and Partitions/NN chunks beyond the first are enumerated and decompressed but their internal framing is only partially reverse-engineered (see recon report §Q6 and §Q7).