API Reference > geometry-core > Curve > CurveChain CurveChain Class Shared base class for use by both open and closed paths. A CurveChain contains only curvePrimitives. No other paths, loops, or regions allowed. A single entry in the chain can in fact contain multiple curve primitives if the entry itself is (for instance) CurveChainWithDistanceIndex which presents itself (through method interface) as a CurvePrimitive with well defined mappings from fraction to xyz, but in fact does all the calculations over multiple primitives. The specific derived classes are Path and Loop CurveChain is an intermediate class. It is not instantiable on its own. Extends CurveCollection Extended by Loop Path Methods Name Description constructor(): CurveChain Protected cloneStroked(options?: StrokeOptions): AnyCurve Abstract Return a structural clone, with CurvePrimitive objects stroked. cyclicCurvePrimitive(index: number): CurvePrimitive | undefined Return the [index] curve primitive, using modulo to mapindex to the cyclic indexing. extendRange(range: Range3d, transform?: Transform): void invoke curve.extendRange(range, transform) for each child getChild(i: number): CurvePrimitive | undefined Return a child by index getPackedStrokes(options?: StrokeOptions): GrowableXYZArray | undefined Stroke the chain into a simple xyz array. reverseChildrenInPlace(): void Reverse each child curve (in place) tryAddChild(child: AnyCurve | undefined): boolean add a child curve. Inherited methods Name Inherited from Description announceToCurveProcessor(processor: RecursiveCurveProcessor): void Abstract CurveCollection Support method for ICurvePrimitive ... checkForNonLinearPrimitives(): boolean CurveCollection return true if the curve collection has any primitives other than LineSegment3d and LineString3d clone(): CurveCollection | undefined CurveCollection Return a deep copy. cloneEmptyPeer(): CurveCollection Abstract CurveCollection clone an empty collection. cloneTransformed(transform: Transform): CurveCollection | undefined CurveCollection Create a deep copy of transformed curves. cloneWithExpandedLineStrings(): CurveCollection | undefined CurveCollection Create a deep copy with all linestrings expanded to multiple LineSegment3d. collectCurvePrimitives(collectorArray?: CurvePrimitive[], smallestPossiblePrimitives: boolean = false): CurvePrimitive[] CurveCollection Return an array containing only the curve primitives. dgnBoundaryType(): number Abstract CurveCollection Return the boundary type of a corresponding MicroStation CurveVector. dispatchToGeometryHandler(handler: GeometryHandler): any Abstract GeometryQuery * "double dispatch" call pattern. isAlmostEqual(other: GeometryQuery): boolean GeometryQuery test for exact structure and nearly identical geometry. isSameGeometryClass(other: GeometryQuery): boolean Abstract GeometryQuery test if (other instanceof this.Type). maxGap(): number CurveCollection return the max gap between adjacent primitives in Path and Loop collections. range(transform?: Transform, result?: Range3d): Range3d GeometryQuery return the range of the entire (tree) GeometryQuery sumLengths(): number CurveCollection Return the sum of the lengths of all contained curves. tryTransformInPlace(transform: Transform): boolean CurveCollection Apply transform recursively to children tryTranslateInPlace(dx: number, dy: number = 0, dz: number = 0): boolean GeometryQuery try to move the geometry by dx,dy,dz createCurveLocationDetailOnAnyCurvePrimitive(source: GeometryQuery | undefined, fraction: number = 0.5): CurveLocationDetail | undefined Static CurveCollection * Find any curve primitive in the source. Properties Name Type Description _curves Protected CurvePrimitive[] The curve primitives in the chain. children Accessor ReadOnly CurvePrimitive[] Return the array of CurvePrimitive Inherited properties Name Type Inherited from Description curveCollectionType Abstract CurveCollectionType CurveCollection Type discriminator. geometryCategory "curveCollection" = "curveCollection" CurveCollection String name for schema properties isAnyRegionType Accessor ReadOnly boolean CurveCollection Return true for planar region types:* Loop* ParityRegion* UnionRegion isClosedPath Accessor ReadOnly boolean CurveCollection Return true for a single-loop planar region type, i.e. Loop.* This is _not- a test for physical closure of a Path isInner boolean CurveCollection Flag for inner loop status. isOpenPath Accessor ReadOnly boolean CurveCollection Return true for a Path, i.e. a chain of curves joined head-to-tail Defined in core/geometry/src/curve/CurveCollection.ts Line 343 Last Updated: 13 June, 2024