Document

Document is OCCTSwift’s XCAF/OCAF document type, wrapping OCCT’s TDocStd_Document and the XDE layer (XCAFDoc_DocumentTool, STEPCAFControl_Reader/Writer). It preserves the full assembly hierarchy, names, colors, PBR materials, GD&T annotations, layer assignments, and OCAF attribute trees from STEP files — and lets you build or edit those structures programmatically. Obtain one via Document.load(from:) (STEP import), Document.create() (blank), or Document.loadOCAF(from:) (native OCAF/binary format).

Document is very large — documented across many pages. This is the core (load/save, assembly structure, AssemblyNode, colors/materials, GD&T, core OCAF attributes); see the other Document — … pages for persistence/IO, XCAF tools, the OCAF attribute zoo, and the many low-level OCCT geometry/math wrappers exposed here.

Topics

• Loading · Assembly Structure · Convenience Methods · Writing · AssemblyNode · GD&T / Dimensions and Tolerances · TNaming: Topological Naming · Errors · Length Unit · Layers · Materials · TDF Label Properties · TDF Reference · TDF CopyLabel · Document Main Label · Document Transactions · Document Undo/Redo · Document Modified Labels · TDataStd Scalar Attributes · TDataStd Integer Array · TDataStd Real Array · TDataStd TreeNode · TDataStd NamedData · TDataXtd Shape Attribute · TDataXtd Position Attribute · TDataXtd Geometry Attribute · TDataXtd Triangulation Attribute · TDataXtd Point/Axis/Plane Attributes

Loading

Document.load(from:progress:)

Load a STEP file with full XDE support (assembly structure, names, colors, materials).

public static func load(from url: URL, progress: ImportProgress? = nil) throws -> Document

• Parameters: url — URL to the STEP file; progress — optional progress/cancellation channel.
• Returns: Document containing the assembly structure.
• Throws: DocumentError.loadFailed if loading fails; ImportError.cancelled if cancelled cooperatively.
• OCCT: STEPCAFControl_Reader with color, name, layer, props, and material modes enabled; XCAFDoc_DocumentTool::ShapeTool/ColorTool/VisMaterialTool.
• Example:

  guard let url = Bundle.main.url(forResource: "assembly", withExtension: "step") else { return }
  let doc = try Document.load(from: url)
  for node in doc.rootNodes {
      print(node.name ?? "<unnamed>", node.children.count)
  }
  

Document.loadSTEP(from:progress:)

Alias for load(from:progress:) with explicit STEP naming.

public static func loadSTEP(from url: URL, progress: ImportProgress? = nil) throws -> Document

• OCCT: STEPCAFControl_Reader (same as load(from:progress:)).

Document.create()

Create a new empty XCAF document.

public static func create() -> Document?

• Returns: A blank Document with empty shape, color, and material tools, or nil on failure.
• OCCT: TDocStd_Application::NewDocument("MDTV-XCAF", …) + XCAFDoc_DocumentTool.
• Example:

  guard let doc = Document.create() else { return }
  let labelId = doc.addShape(Shape.box(width: 10, height: 10, depth: 10)!)
  

Assembly Structure

rootNodes

Get the root nodes (top-level/free shapes) in the document.

public var rootNodes: [AssemblyNode] { get }

• Returns: Array of top-level AssemblyNode values. Assemblies have children; parts have a shape.
• OCCT: XCAFDoc_ShapeTool free-shape enumeration via OCCTDocumentGetRootCount / OCCTDocumentGetRootLabelId.
• Example:

  func printTree(_ node: AssemblyNode, indent: Int = 0) {
      print(String(repeating: "  ", count: indent) + (node.name ?? "<unnamed>"))
      for child in node.children { printTree(child, indent: indent + 1) }
  }
  doc.rootNodes.forEach { printTree($0) }
  

node(at:)

Look up an AssemblyNode by its XCAF labelId.

public func node(at labelId: Int64) -> AssemblyNode?

labelId values are stable within a single Document instance; round-trip via AssemblyNode.labelId.

• Parameters: labelId — the identifier previously obtained from rootNodes traversal or a shapeLabelId(at:) call.
• Returns: The matching node, or nil if the labelId does not refer to a label in this document.
• OCCT: TDF_Label look-up in the document’s label registry (OCCTDocumentLabelIsNull).
• Example:

  let id = doc.rootNodes.first?.labelId ?? -1
  if let node = doc.node(at: id) {
      print(node.name ?? "")
  }
  

Convenience Methods

allShapes()

Get all shapes from the document as a flat list (depth-first traversal).

public func allShapes() -> [Shape]

• Returns: Every Shape found by recursing rootNodes. Pure assemblies that have no direct geometry contribute no shapes.
• Example:

  let shapes = doc.allShapes()
  print("Total parts:", shapes.count)
  

shapesWithColors()

Get all shapes with their associated colors.

public func shapesWithColors() -> [(shape: Shape, color: Color?)]

• Returns: Array of (shape, color?) pairs; color is nil for uncolored nodes.
• Example:

  for (shape, color) in doc.shapesWithColors() {
      if let c = color { print("color:", c.red, c.green, c.blue) }
  }
  

shapesWithMaterials()

Get all shapes with their associated PBR materials.

public func shapesWithMaterials() -> [(shape: Shape, material: Material?)]

• Returns: Array of (shape, material?) pairs; material is nil for nodes without a PBR material.

Writing

write(to:)

Write the document to a STEP file, preserving assembly structure, colors, and materials.

public func write(to url: URL) throws

• Parameters: url — output file URL.
• Throws: DocumentError.writeFailed if writing fails.
• OCCT: STEPCAFControl_Writer with color, name, layer, props, and material modes.
• Example:

  let out = URL(fileURLWithPath: "/tmp/export.step")
  try doc.write(to: out)
  

writeSTEP(to:progress:)

Write the document to a STEP file with optional progress and cancellation.

public func writeSTEP(to url: URL, progress: ImportProgress?) throws

• Parameters: url — output URL; progress — optional progress/cancellation channel.
• Throws: ImportError.cancelled if cancelled; ImportError.importFailed on other failure.
• OCCT: STEPCAFControl_Writer (via OCCTDocumentWriteSTEPProgress).

AssemblyNode

AssemblyNode represents a node in an XDE assembly tree — a part or sub-assembly in a STEP file with name, transform, color, PBR material, child nodes, and shape geometry.

public final class AssemblyNode: @unchecked Sendable

AssemblyNode holds an unowned reference to its parent Document and is invalidated when the document is released.

labelId

The XCAF label identifier for this node.

public let labelId: Int64

Stable within a single Document instance; pass it back to Document.node(at:) to recover the node.

name

The name of this node (from CAD software).

public var name: String? { get }

• Returns: The label name string, or nil if unnamed.
• OCCT: TDataStd_Name attribute on the label (via OCCTDocumentGetLabelName).

isAssembly

Whether this node is an assembly (has children).

public var isAssembly: Bool { get }

• OCCT: XCAFDoc_ShapeTool::IsAssembly (via OCCTDocumentIsAssembly).

isReference

Whether this node is a reference (instance of another shape).

public var isReference: Bool { get }

• OCCT: XCAFDoc_ShapeTool::IsReference (via OCCTDocumentIsReference).

transform

Transform matrix (position/rotation relative to parent), as a column-major simd_float4x4.

public var transform: simd_float4x4 { get }

• OCCT: XCAFDoc_Location attribute (via OCCTDocumentGetLocation).

color

Color assigned to this node (if any). Checks surface color first, then generic.

public var color: Color? { get }

• Returns: Color (RGBA in 0–1 range), or nil if no color is assigned.
• OCCT: XCAFDoc_ColorTool::GetColor with XCAFDoc_ColorSurf then XCAFDoc_ColorGen.

setColor(_:)

Set the surface color on this node.

public func setColor(_ color: Color)

• Parameters: color — the color to assign.
• OCCT: XCAFDoc_ColorTool::SetColor with XCAFDoc_ColorSurf (via OCCTDocumentSetLabelColor).
• Example:

  node.setColor(Color(red: 1, green: 0, blue: 0, alpha: 1))
  

setColor(_:type:)

Set the color on this node with a specific color type.

public func setColor(_ color: Color, type: OCCTColorType)

• Parameters: color — the color to assign; type — OCCTColorTypeGeneric (0), OCCTColorTypeSurface (1), or OCCTColorTypeCurve (2).
• OCCT: XCAFDoc_ColorTool::SetColor (via OCCTDocumentSetLabelColor).

setMaterial(_:)

Set the PBR material on this node.

public func setMaterial(_ material: Material)

• Parameters: material — Material struct with base color, metallic, roughness, emissive, and transparency.
• OCCT: XCAFDoc_VisMaterialTool::SetShapeMaterial (via OCCTDocumentSetLabelMaterial).

material

PBR material assigned to this node (if any).

public var material: Material? { get }

• Returns: Material with PBR properties, or nil if none is assigned.
• OCCT: XCAFDoc_VisMaterialTool::GetShapeMaterial (via OCCTDocumentGetLabelMaterial).

children

Child nodes for assemblies.

public var children: [AssemblyNode] { get }

• Returns: Array of direct child AssemblyNode values; empty for leaf parts.
• OCCT: TDF_Label child iteration (via OCCTDocumentGetChildCount / OCCTDocumentGetChildLabelId).

shape

The shape geometry with transform applied.

public var shape: Shape? { get }

• Returns: Shape with the node’s TopLoc_Location baked in, or nil for pure assemblies with no direct geometry.
• OCCT: XCAFDoc_ShapeTool::GetShape + TopLoc_Location (via OCCTDocumentGetShapeWithLocation).

shapeWithoutTransform

The shape geometry without transform (original definition).

public var shapeWithoutTransform: Shape? { get }

• Returns: The un-located shape, or nil if none is attached.
• OCCT: XCAFDoc_ShapeTool::GetShape without location (via OCCTDocumentGetShape).

referredNode

For references, get the referred (prototype) node.

public var referredNode: AssemblyNode? { get }

• Returns: The prototype node this reference points to, or nil if isReference is false.
• OCCT: XCAFDoc_ShapeTool::GetReferredShape (via OCCTDocumentGetReferredLabelId).

GD&T / Dimensions and Tolerances

Supporting types for GD&T data read from STEP files.

DimensionInfo

Dimension information from STEP GD&T data.

public struct DimensionInfo: Sendable {
    public let type: Int32         // XCAFDimTolObjects_DimensionType
    public let value: Double       // primary dimension value
    public let lowerTolerance: Double
    public let upperTolerance: Double
}

GeomToleranceInfo

Geometric tolerance information from STEP GD&T data.

public struct GeomToleranceInfo: Sendable {
    public let type: Int32   // XCAFDimTolObjects_GeomToleranceType
    public let value: Double
}

DatumInfo

Datum reference information from STEP GD&T data.

public struct DatumInfo: Sendable {
    public let name: String   // e.g. "A", "B", "C"
}

dimensionCount

Number of dimensions defined in this document.

public var dimensionCount: Int { get }

• OCCT: XCAFDoc_DimTolTool::GetDimensionLabels (via OCCTDocumentGetDimensionCount).

geomToleranceCount

Number of geometric tolerances defined in this document.

public var geomToleranceCount: Int { get }

• OCCT: XCAFDoc_DimTolTool (via OCCTDocumentGetGeomToleranceCount).

datumCount

Number of datums defined in this document.

public var datumCount: Int { get }

• OCCT: XCAFDoc_DimTolTool (via OCCTDocumentGetDatumCount).

dimension(at:)

Get dimension info at the given index.

public func dimension(at index: Int) -> DimensionInfo?

• Parameters: index — zero-based dimension index.
• Returns: DimensionInfo, or nil if index is out of range.
• OCCT: XCAFDimTolObjects_DimensionObject (via OCCTDocumentGetDimensionInfo).

geomTolerance(at:)

Get geometric tolerance info at the given index.

public func geomTolerance(at index: Int) -> GeomToleranceInfo?

• Returns: GeomToleranceInfo, or nil if index is out of range.
• OCCT: XCAFDimTolObjects_GeomToleranceObject (via OCCTDocumentGetGeomToleranceInfo).

datum(at:)

Get datum info at the given index.

public func datum(at index: Int) -> DatumInfo?

• Returns: DatumInfo, or nil if index is out of range.
• OCCT: XCAFDimTolObjects_DatumObject (via OCCTDocumentGetDatumInfo).

dimensions

All dimensions in this document.

public var dimensions: [DimensionInfo] { get }

geomTolerances

All geometric tolerances in this document.

public var geomTolerances: [GeomToleranceInfo] { get }

datums

All datums in this document.

public var datums: [DatumInfo] { get }

• Example:

  let doc = try Document.load(from: gdt_step_url)
  print("Dimensions:", doc.dimensions.count)
  print("Tolerances:", doc.geomTolerances.count)
  for datum in doc.datums { print("Datum:", datum.name) }
  

TNaming: Topological Naming

Types and methods for persistent topological naming (TNaming_NamedShape, TNaming_Builder).

NamingEvolution

Evolution type for topological naming history.

public enum NamingEvolution: Int32, Sendable {
    case primitive = 0   // Created from scratch (no predecessor)
    case generated = 1   // Generated from another shape
    case modify    = 2   // Modified (e.g. filleted edge)
    case delete    = 3   // Deleted
    case selected  = 4   // Named selection for persistent identification
}

NamingHistoryEntry

A single entry in the naming history of a label.

public struct NamingHistoryEntry: Sendable {
    public let evolution: NamingEvolution
    public let hasOldShape: Bool
    public let hasNewShape: Bool
    public let isModification: Bool
}

createLabel(parent:)

Create a new TDF label for naming history tracking.

public func createLabel(parent: AssemblyNode? = nil) -> AssemblyNode?

• Parameters: parent — parent node; pass nil to create under the document main label.
• Returns: AssemblyNode representing the new label, or nil on failure.
• OCCT: TDF_Label::NewChild (via OCCTDocumentCreateLabel).

recordNaming(on:evolution:oldShape:newShape:)

Record a naming evolution on a label.

@discardableResult
public func recordNaming(on node: AssemblyNode, evolution: NamingEvolution,
                         oldShape: Shape? = nil, newShape: Shape? = nil) -> Bool

• Parameters:
  • node — the label to record on.
  • evolution — type of topological evolution.
  • oldShape — predecessor shape (nil for .primitive).
  • newShape — result shape (nil for .delete).
• Returns: true if recording succeeded.
• OCCT: TNaming_Builder::Generated/Modify/Delete/Select (via OCCTDocumentNamingRecord).

currentShape(on:)

Get the current (most recent) shape on a label.

public func currentShape(on node: AssemblyNode) -> Shape?

• OCCT: TNaming_Tool::CurrentShape + TNaming_NamedShape (via OCCTDocumentNamingGetCurrentShape).

storedShape(on:)

Get the stored shape on a label.

public func storedShape(on node: AssemblyNode) -> Shape?

• OCCT: TNaming_Tool::GetShape (via OCCTDocumentNamingGetShape).

namingEvolution(on:)

Get the naming evolution type on a label.

public func namingEvolution(on node: AssemblyNode) -> NamingEvolution?

• Returns: The NamingEvolution case, or nil if no naming attribute exists.
• OCCT: TNaming_NamedShape::Evolution (via OCCTDocumentNamingGetEvolution).

namingHistory(on:)

Get the full naming history on a label.

public func namingHistory(on node: AssemblyNode) -> [NamingHistoryEntry]

• Returns: Array of NamingHistoryEntry values ordered from oldest to newest.
• OCCT: TNaming_Iterator over TNaming_NamedShape (via OCCTDocumentNamingHistoryCount / OCCTDocumentNamingGetHistoryEntry).

oldShape(on:at:)

Get the old (input) shape from a history entry.

public func oldShape(on node: AssemblyNode, at index: Int) -> Shape?

• Parameters: index — zero-based history index.
• OCCT: TNaming_Iterator (via OCCTDocumentNamingGetOldShape).

newShape(on:at:)

Get the new (result) shape from a history entry.

public func newShape(on node: AssemblyNode, at index: Int) -> Shape?

• OCCT: TNaming_Iterator (via OCCTDocumentNamingGetNewShape).

tracedForward(from:scope:)

Trace forward: find shapes generated/modified from the given shape.

public func tracedForward(from shape: Shape, scope: AssemblyNode) -> [Shape]

• Parameters: shape — the source shape; scope — label providing document scope.
• Returns: Shapes that were generated or modified from shape (up to 64).
• OCCT: TNaming_Tool::GeneratedShape / forward-tracing (via OCCTDocumentNamingTraceForward).

tracedBackward(from:scope:)

Trace backward: find shapes that generated/preceded the given shape.

public func tracedBackward(from shape: Shape, scope: AssemblyNode) -> [Shape]

• Parameters: shape — the shape to trace back from; scope — label scope.
• Returns: Predecessor shapes (up to 64).
• OCCT: TNaming_Tool backward-tracing (via OCCTDocumentNamingTraceBackward).

selectShape(_:context:on:)

Create a persistent named selection.

@discardableResult
public func selectShape(_ selection: Shape, context: Shape, on node: AssemblyNode) -> Bool

• Parameters: selection — sub-shape to select; context — containing shape; node — label to store on.
• OCCT: TNaming_Builder::Select (via OCCTDocumentNamingSelect).

resolveShape(on:)

Resolve a previously selected shape after modifications.

public func resolveShape(on node: AssemblyNode) -> Shape?

• Returns: The resolved shape, or nil if resolution fails.
• OCCT: TNaming_Selector::Solve (via OCCTDocumentNamingResolve).

Errors

DocumentError

Errors that can occur when working with XDE documents.

public enum DocumentError: Error, LocalizedError {
    case loadFailed(url: URL)
    case writeFailed(url: URL)
}

errorDescription produces a human-readable message such as "Failed to load STEP file: assembly.step".

Length Unit

LengthUnit

Length unit information from a document.

public struct LengthUnit: Sendable {
    public let scale: Double   // e.g. 1.0 for mm, 25.4 for inch, 1000.0 for m
    public let name: String    // e.g. "mm", "inch", "m"
}

lengthUnit

Get the length unit of this document.

public var lengthUnit: LengthUnit? { get }

Common scale values: 1.0 = mm, 10.0 = cm, 1000.0 = m, 25.4 = inch.

• Returns: LengthUnit with scale and name, or nil if not set.
• OCCT: STEPCAFControl_Reader unit info (via OCCTDocumentGetLengthUnit).
• Example:

  if let unit = doc.lengthUnit {
      print("Unit:", unit.name, "scale:", unit.scale)
  }
  

Layers

layerCount

Number of layers in this document.

public var layerCount: Int { get }

• OCCT: XCAFDoc_LayerTool (via OCCTDocumentGetLayerCount).

layerName(at:)

Get the name of a layer by index.

public func layerName(at index: Int) -> String?

• Parameters: index — zero-based layer index.
• Returns: Layer name, or nil if out of range.
• OCCT: XCAFDoc_LayerTool (via OCCTDocumentGetLayerName).

layerNames

All layer names in this document.

public var layerNames: [String] { get }

• Example:

  print("Layers:", doc.layerNames.joined(separator: ", "))
  

Materials

MaterialInfo

Material information from a document.

public struct MaterialInfo: Sendable {
    public let name: String
    public let description: String
    public let density: Double
}

materialCount

Number of materials in this document.

public var materialCount: Int { get }

• OCCT: XCAFDoc_MaterialTool::GetMaterialLabels (via OCCTDocumentGetMaterialCount).

materialInfo(at:)

Get material info by index.

public func materialInfo(at index: Int) -> MaterialInfo?

• Parameters: index — zero-based material index.
• Returns: MaterialInfo, or nil if out of range.
• OCCT: XCAFDoc_MaterialTool::GetMaterial (via OCCTDocumentGetMaterialInfo).

materials

All materials in this document.

public var materials: [MaterialInfo] { get }

• Example:

  for mat in doc.materials {
      print(mat.name, "density:", mat.density)
  }
  

TDF Label Properties

Extensions on AssemblyNode exposing low-level TDF_Label properties.

tag

The tag integer identifying this label among its siblings.

public var tag: Int32 { get }

• OCCT: TDF_Label::Tag (via OCCTDocumentLabelTag).

depth

The depth of this label in the tree (root = 0, main = 1, etc.).

public var depth: Int32 { get }

• OCCT: TDF_Label::Depth (via OCCTDocumentLabelDepth).

isNull

Whether this label is null.

public var isNull: Bool { get }

• OCCT: TDF_Label::IsNull.

isRoot

Whether this label is the root label (0:).

public var isRoot: Bool { get }

• OCCT: TDF_Label::IsRoot.

father

The parent (father) node of this label.

public var father: AssemblyNode? { get }

• Returns: The parent node, or nil if this is the root.
• OCCT: TDF_Label::Father.

root

The root node of the data framework.

public var root: AssemblyNode? { get }

• OCCT: TDF_Label::Root.

hasAttribute

Whether this label has any attributes.

public var hasAttribute: Bool { get }

• OCCT: TDF_Label::HasAttribute.

attributeCount

The number of attributes on this label.

public var attributeCount: Int32 { get }

• OCCT: TDF_Label::NbAttributes.

hasChild

Whether this label has any child labels.

public var hasChild: Bool { get }

• OCCT: TDF_Label::HasChild.

childCount

The number of direct child labels.

public var childCount: Int32 { get }

• OCCT: TDF_Label::NbChildren.

findChild(tag:create:)

Find or create a child label by tag.

public func findChild(tag: Int32, create: Bool = false) -> AssemblyNode?

• Parameters: tag — tag to search for; create — if true, create the child if it doesn’t exist.
• Returns: The child node, or nil if not found and create is false.
• OCCT: TDF_Label::FindChild.

forgetAllAttributes(clearChildren:)

Remove all attributes from this label.

public func forgetAllAttributes(clearChildren: Bool = true)

• Parameters: clearChildren — if true, also clears attributes on child labels.
• OCCT: TDF_Label::ForgetAllAttributes.

descendants(allLevels:)

Get all descendant labels.

public func descendants(allLevels: Bool = false) -> [AssemblyNode]

• Parameters: allLevels — if true, recurse all descendants; if false, direct children only.
• Returns: Array of descendant nodes (up to 1,024).
• OCCT: TDF_LabelSequence recursive traversal (via OCCTDocumentGetDescendantLabels).

setName(_:)

Set the name (TDataStd_Name) on this label.

@discardableResult
public func setName(_ name: String) -> Bool

• Returns: true if the name was set successfully.
• OCCT: TDataStd_Name::Set (via OCCTDocumentSetLabelName).

TDF Reference

setReference(to:)

Set a TDF_Reference from this label to another label.

@discardableResult
public func setReference(to target: AssemblyNode) -> Bool

• OCCT: TDF_Reference::Set (via OCCTDocumentLabelSetReference).

referencedLabel

Get the label referenced by a TDF_Reference attribute on this label.

public var referencedLabel: AssemblyNode? { get }

• Returns: The referenced node, or nil if no TDF_Reference attribute exists.
• OCCT: TDF_Reference::Get (via OCCTDocumentLabelGetReference).

TDF CopyLabel

copyLabel(from:to:)

Copy a label and all its attributes to a destination label.

@discardableResult
public func copyLabel(from source: AssemblyNode, to destination: AssemblyNode) -> Bool

• Parameters: source — label to copy from; destination — label to copy to.
• Returns: true if the copy succeeded.
• OCCT: TDF_CopyLabel (via OCCTDocumentCopyLabel).

Document Main Label

mainLabel

The main label (0:1) of the document — the root of the user data tree.

public var mainLabel: AssemblyNode? { get }

• OCCT: TDocStd_Document::Main() (via OCCTDocumentGetMainLabel).
• Example:

  if let main = doc.mainLabel {
      _ = main.setName("MyModel")
  }
  

Document Transactions

openTransaction()

Open a new transaction (command) on the document.

public func openTransaction()

All changes made after this call can be committed or aborted.

• OCCT: TDocStd_Document::NewCommand (via OCCTDocumentOpenTransaction).

commitTransaction()

Commit the current transaction.

@discardableResult
public func commitTransaction() -> Bool

• Returns: true if committed successfully.
• OCCT: TDocStd_Document::CommitCommand.

abortTransaction()

Abort the current transaction, undoing all changes since openTransaction().

public func abortTransaction()

• OCCT: TDocStd_Document::AbortCommand.

hasOpenTransaction

Whether a transaction is currently open.

public var hasOpenTransaction: Bool { get }

• OCCT: TDocStd_Document::HasOpenCommand.
• Example:

  doc.openTransaction()
  _ = doc.mainLabel?.setName("Rev1")
  _ = doc.commitTransaction()
  

Document Undo/Redo

setUndoLimit(_:)

Set the maximum number of undo steps.

public func setUndoLimit(_ limit: Int)

Must be called before any transactions. Pass 0 to disable undo.

• OCCT: TDocStd_Document::SetUndoLimit.

undoLimit

The maximum number of undo steps.

public var undoLimit: Int { get }

• OCCT: TDocStd_Document::GetUndoLimit.

undo()

Perform undo (reverses the last committed transaction).

@discardableResult
public func undo() -> Bool

• Returns: true if undo was performed.
• OCCT: TDocStd_Document::Undo.

redo()

Perform redo (reapplies the last undone transaction).

@discardableResult
public func redo() -> Bool

• Returns: true if redo was performed.
• OCCT: TDocStd_Document::Redo.

availableUndos

The number of available undo steps.

public var availableUndos: Int { get }

• OCCT: TDocStd_Document::GetAvailableUndos.

availableRedos

The number of available redo steps.

public var availableRedos: Int { get }

• OCCT: TDocStd_Document::GetAvailableRedos.
• Example:

  doc.setUndoLimit(10)
  doc.openTransaction()
  _ = doc.mainLabel?.setInteger(42)
  _ = doc.commitTransaction()
  print("Undos available:", doc.availableUndos)
  _ = doc.undo()
  

Document Modified Labels

setModified(_:)

Mark a label as modified.

public func setModified(_ node: AssemblyNode)

• OCCT: TDocStd_Document::SetModified (via OCCTDocumentSetModified).

clearModified()

Clear all modification marks.

public func clearModified()

• OCCT: TDocStd_Document::PurgeModified (via OCCTDocumentClearModified).

isModified(_:)

Check if a label is marked as modified.

public func isModified(_ node: AssemblyNode) -> Bool

• OCCT: TDocStd_Document::IsModified (via OCCTDocumentIsLabelModified).

TDataStd Scalar Attributes

Extensions on AssemblyNode for TDataStd scalar attribute types.

setInteger(_:)

Set an integer attribute (TDataStd_Integer) on this label.

@discardableResult
public func setInteger(_ value: Int32) -> Bool

• OCCT: TDataStd_Integer::Set (via OCCTDocumentSetIntegerAttr).

integer

Get the integer attribute from this label.

public var integer: Int32? { get }

• Returns: The stored value, or nil if no TDataStd_Integer exists.
• OCCT: TDataStd_Integer::Get (via OCCTDocumentGetIntegerAttr).

setReal(_:)

Set a real attribute (TDataStd_Real) on this label.

@discardableResult
public func setReal(_ value: Double) -> Bool

• OCCT: TDataStd_Real::Set (via OCCTDocumentSetRealAttr).

real

Get the real attribute from this label.

public var real: Double? { get }

• OCCT: TDataStd_Real::Get (via OCCTDocumentGetRealAttr).

setAsciiString(_:)

Set an ASCII string attribute (TDataStd_AsciiString) on this label.

@discardableResult
public func setAsciiString(_ value: String) -> Bool

• OCCT: TDataStd_AsciiString::Set (via OCCTDocumentSetAsciiStringAttr).

asciiString

Get the ASCII string attribute from this label.

public var asciiString: String? { get }

• OCCT: TDataStd_AsciiString::Get (via OCCTDocumentGetAsciiStringAttr).

setComment(_:)

Set a comment attribute (TDataStd_Comment) on this label.

@discardableResult
public func setComment(_ value: String) -> Bool

• OCCT: TDataStd_Comment::Set (via OCCTDocumentSetCommentAttr).

comment

Get the comment attribute from this label.

public var comment: String? { get }

• OCCT: TDataStd_Comment::Get (via OCCTDocumentGetCommentAttr).
• Example:

  guard let label = doc.createLabel() else { return }
  _ = label.setReal(3.14159)
  _ = label.setComment("pi approximation")
  print(label.real ?? 0, label.comment ?? "")
  

TDataStd Integer Array

initIntegerArray(lower:upper:)

Initialize an integer array attribute on this label.

@discardableResult
public func initIntegerArray(lower: Int32, upper: Int32) -> Bool

• Parameters: lower, upper — inclusive bounds of the array.
• OCCT: TDataStd_IntegerArray::Init (via OCCTDocumentInitIntegerArray).

setIntegerArrayValue(at:value:)

Set a value in the integer array attribute.

@discardableResult
public func setIntegerArrayValue(at index: Int32, value: Int32) -> Bool

• OCCT: TDataStd_IntegerArray::SetValue (via OCCTDocumentSetIntegerArrayValue).

integerArrayValue(at:)

Get a value from the integer array attribute.

public func integerArrayValue(at index: Int32) -> Int32?

• Returns: The value, or nil if the attribute doesn’t exist or index is out of bounds.
• OCCT: TDataStd_IntegerArray::Value (via OCCTDocumentGetIntegerArrayValue).

integerArrayBounds

Get the bounds of the integer array attribute.

public var integerArrayBounds: (lower: Int32, upper: Int32)? { get }

• OCCT: TDataStd_IntegerArray::Lower/Upper (via OCCTDocumentGetIntegerArrayBounds).
• Example:

  guard let label = doc.createLabel() else { return }
  _ = label.initIntegerArray(lower: 0, upper: 2)
  _ = label.setIntegerArrayValue(at: 0, value: 10)
  _ = label.setIntegerArrayValue(at: 1, value: 20)
  _ = label.setIntegerArrayValue(at: 2, value: 30)
  print(label.integerArrayValue(at: 1) ?? -1)  // 20
  

TDataStd Real Array

initRealArray(lower:upper:)

Initialize a real array attribute on this label.

@discardableResult
public func initRealArray(lower: Int32, upper: Int32) -> Bool

• OCCT: TDataStd_RealArray::Init (via OCCTDocumentInitRealArray).

setRealArrayValue(at:value:)

Set a value in the real array attribute.

@discardableResult
public func setRealArrayValue(at index: Int32, value: Double) -> Bool

• OCCT: TDataStd_RealArray::SetValue (via OCCTDocumentSetRealArrayValue).

realArrayValue(at:)

Get a value from the real array attribute.

public func realArrayValue(at index: Int32) -> Double?

• OCCT: TDataStd_RealArray::Value (via OCCTDocumentGetRealArrayValue).

realArrayBounds

Get the bounds of the real array attribute.

public var realArrayBounds: (lower: Int32, upper: Int32)? { get }

• OCCT: TDataStd_RealArray::Lower/Upper (via OCCTDocumentGetRealArrayBounds).

TDataStd TreeNode

setTreeNode()

Set a tree node attribute (TDataStd_TreeNode) on this label.

@discardableResult
public func setTreeNode() -> Bool

• OCCT: TDataStd_TreeNode::Set (via OCCTDocumentSetTreeNode).

appendTreeChild(_:)

Append a child to this tree node.

@discardableResult
public func appendTreeChild(_ child: AssemblyNode) -> Bool

• OCCT: TDataStd_TreeNode::Append (via OCCTDocumentAppendTreeChild).

treeNodeFather

The father (parent) of this tree node.

public var treeNodeFather: AssemblyNode? { get }

• OCCT: TDataStd_TreeNode::Father (via OCCTDocumentTreeNodeFather).

treeNodeFirstChild

The first child of this tree node.

public var treeNodeFirstChild: AssemblyNode? { get }

• OCCT: TDataStd_TreeNode::First (via OCCTDocumentTreeNodeFirst).

treeNodeNext

The next sibling of this tree node.

public var treeNodeNext: AssemblyNode? { get }

• OCCT: TDataStd_TreeNode::Next (via OCCTDocumentTreeNodeNext).

treeNodeHasFather

Whether this tree node has a father.

public var treeNodeHasFather: Bool { get }

• OCCT: TDataStd_TreeNode::HasFather.

treeNodeDepth

The depth of this tree node (root = 0).

public var treeNodeDepth: Int32 { get }

• OCCT: TDataStd_TreeNode::Depth.

treeNodeChildCount

The number of children of this tree node.

public var treeNodeChildCount: Int32 { get }

• OCCT: TDataStd_TreeNode::NbChildren.
• Example:

  guard let parent = doc.createLabel(),
        let child1 = doc.createLabel(),
        let child2 = doc.createLabel() else { return }
  _ = parent.setTreeNode()
  _ = child1.setTreeNode()
  _ = child2.setTreeNode()
  _ = parent.appendTreeChild(child1)
  _ = parent.appendTreeChild(child2)
  print("Children:", parent.treeNodeChildCount)  // 2
  

TDataStd NamedData

setNamedInteger(_:value:)

Set a named integer value on this label.

@discardableResult
public func setNamedInteger(_ name: String, value: Int32) -> Bool

• OCCT: TDataStd_NamedData::SetInteger (via OCCTDocumentNamedDataSetInteger).

namedInteger(_:)

Get a named integer value from this label.

public func namedInteger(_ name: String) -> Int32?

• OCCT: TDataStd_NamedData::GetInteger (via OCCTDocumentNamedDataGetInteger).

hasNamedInteger(_:)

Check if a named integer exists on this label.

public func hasNamedInteger(_ name: String) -> Bool

• OCCT: TDataStd_NamedData::HasInteger.

setNamedReal(_:value:)

Set a named real value on this label.

@discardableResult
public func setNamedReal(_ name: String, value: Double) -> Bool

• OCCT: TDataStd_NamedData::SetReal (via OCCTDocumentNamedDataSetReal).

namedReal(_:)

Get a named real value from this label.

public func namedReal(_ name: String) -> Double?

• OCCT: TDataStd_NamedData::GetReal.

hasNamedReal(_:)

Check if a named real exists on this label.

public func hasNamedReal(_ name: String) -> Bool

setNamedString(_:value:)

Set a named string value on this label.

@discardableResult
public func setNamedString(_ name: String, value: String) -> Bool

• OCCT: TDataStd_NamedData::SetString (via OCCTDocumentNamedDataSetString).

namedString(_:)

Get a named string value from this label.

public func namedString(_ name: String) -> String?

• OCCT: TDataStd_NamedData::GetString.

hasNamedString(_:)

Check if a named string exists on this label.

public func hasNamedString(_ name: String) -> Bool

• Example:

  guard let label = doc.createLabel() else { return }
  _ = label.setNamedReal("mass_kg", value: 2.75)
  _ = label.setNamedString("material", value: "Aluminium 6061")
  print(label.namedReal("mass_kg") ?? 0)        // 2.75
  print(label.namedString("material") ?? "")    // Aluminium 6061
  

TDataXtd Shape Attribute

GeometryType

Geometry type for TDataXtd_Geometry attributes.

public enum GeometryType: Int32 {
    case anyGeom  = 0
    case point    = 1
    case line     = 2
    case circle   = 3
    case ellipse  = 4
    case spline   = 5
    case plane    = 6
    case cylinder = 7
}

ExecutionStatus

Execution status for TFunction graph nodes.

public enum ExecutionStatus: Int32 {
    case wrongDefinition = 0
    case notExecuted     = 1
    case executing       = 2
    case succeeded       = 3
    case failed          = 4
}

setShapeAttribute(_:)

Set a shape attribute on this label (stores the shape via TNaming).

@discardableResult
public func setShapeAttribute(_ shape: Shape) -> Bool

• OCCT: TDataXtd_Shape::Set (via OCCTDocumentSetShapeAttr).

shapeAttribute()

Get the shape stored in a TDataXtd_Shape attribute on this label.

public func shapeAttribute() -> Shape?

• OCCT: TDataXtd_Shape::Get (via OCCTDocumentGetShapeAttr).

hasShapeAttribute

Check if this label has a TDataXtd_Shape attribute.

public var hasShapeAttribute: Bool { get }

• OCCT: TDataXtd_Shape::Find.

TDataXtd Position Attribute

setPositionAttribute(x:y:z:)

Set a position (3D point) attribute on this label.

@discardableResult
public func setPositionAttribute(x: Double, y: Double, z: Double) -> Bool

• OCCT: TDataXtd_Position::Set (via OCCTDocumentSetPositionAttr).

positionAttribute()

Get the position attribute from this label.

public func positionAttribute() -> (x: Double, y: Double, z: Double)?

• Returns: The stored position, or nil if no attribute exists.
• OCCT: TDataXtd_Position::Get (via OCCTDocumentGetPositionAttr).

hasPositionAttribute

Check if this label has a TDataXtd_Position attribute.

public var hasPositionAttribute: Bool { get }

TDataXtd Geometry Attribute

setGeometryType(_:)

Set a geometry type attribute on this label.

@discardableResult
public func setGeometryType(_ type: GeometryType) -> Bool

• OCCT: TDataXtd_Geometry::Set (via OCCTDocumentSetGeometryAttr).

geometryType()

Get the geometry type from this label.

public func geometryType() -> GeometryType?

• Returns: The GeometryType case, or nil if no attribute exists.
• OCCT: TDataXtd_Geometry::GetType (via OCCTDocumentGetGeometryType).

hasGeometryAttribute

Check if this label has a TDataXtd_Geometry attribute.

public var hasGeometryAttribute: Bool { get }

TDataXtd Triangulation Attribute

setTriangulationFromShape(_:deflection:)

Set a triangulation attribute on this label by meshing a shape.

@discardableResult
public func setTriangulationFromShape(_ shape: Shape, deflection: Double = 1.0) -> Bool

• Parameters: shape — the shape to tessellate; deflection — linear deflection for meshing (default 1.0).
• OCCT: BRepMesh_IncrementalMesh + TDataXtd_Triangulation::Set (via OCCTDocumentSetTriangulationFromShape).

triangulationNodeCount

Get the number of nodes in the triangulation attribute.

public var triangulationNodeCount: Int32 { get }

• OCCT: Poly_Triangulation::NbNodes (via OCCTDocumentTriangulationNbNodes).

triangulationTriangleCount

Get the number of triangles in the triangulation attribute.

public var triangulationTriangleCount: Int32 { get }

• OCCT: Poly_Triangulation::NbTriangles (via OCCTDocumentTriangulationNbTriangles).

triangulationDeflection

Get the deflection of the triangulation attribute.

public var triangulationDeflection: Double { get }

• OCCT: Poly_Triangulation::Deflection (via OCCTDocumentTriangulationDeflection).

TDataXtd Point/Axis/Plane Attributes

setPointAttribute(x:y:z:)

Set a point attribute on this label.

@discardableResult
public func setPointAttribute(x: Double, y: Double, z: Double) -> Bool

• OCCT: TDataXtd_Point::Set (via OCCTDocumentSetPointAttr).

setAxisAttribute(originX:originY:originZ:directionX:directionY:directionZ:)

Set an axis attribute on this label (origin + direction).

@discardableResult
public func setAxisAttribute(originX: Double, originY: Double, originZ: Double,
                              directionX: Double, directionY: Double, directionZ: Double) -> Bool

• OCCT: TDataXtd_Axis::Set (via OCCTDocumentSetAxisAttr).

setPlaneAttribute(originX:originY:originZ:normalX:normalY:normalZ:)

Set a plane attribute on this label (origin + normal).

@discardableResult
public func setPlaneAttribute(originX: Double, originY: Double, originZ: Double,
                               normalX: Double, normalY: Double, normalZ: Double) -> Bool

• OCCT: TDataXtd_Plane::Set (via OCCTDocumentSetPlaneAttr).
• Example:

  guard let label = doc.createLabel() else { return }
  _ = label.setPlaneAttribute(originX: 0, originY: 0, originZ: 5,
                               normalX: 0, normalY: 0, normalZ: 1)