Query: Curve

Curve queries — read-only geometric questions about curves (lines, arcs and splines) and the relationships between two curves. Every method takes opaque curve handles (CurveHandle / LineHandle) and point handles (Vec3Handle) and returns plain values — points as Vec3Components, lengths/distances/parameters as number, predicates as boolean. Relationship methods that produce a new curve return a CurveHandle (or null when there is no result). No query mutates its inputs. Lengths and distances are in Snaptrude units — convert with snaptrude.core.units.convert(value, from, to). Accessed via snaptrude.core.geom.query.curve.

Splines

A CurveHandle is a line, an arc, or a NURBS spline (minted by core.geom.create.splineFromPoints or splineFromControlPoints). Every method here accepts a spline at compile time, but only the reads backed by the engine's spline math answer for one today. The rest throw PRECONDITION_FAILED ("<member> is not supported for splines yet") — a typed refusal, never a quietly wrong answer.

Splines	Members
supported	`getStartPoint`, `getEndPoint`, `getLength`, `getTangent`, `listPoints`, `getNearestPoint`
not yet	`getMidPoint`, `getChordLength`, `getNormal`, `getProjection`, `getPointAtDistance`, `getParameterAtPoint`, `getCurvature`, `getDistanceToPoint`, `getDistanceAlong`, `listSubdivisions`, `isLinear`, `isOnCurve`, `hasPoint`, `isEqual`, `isOverlapping`, `getCommonPart`, `listIntersections`, `getMergedCurve`, `isContinuous`, `isParallel`, `getShortestGap`, `getDistanceBetween`

isOverlapping is deliberately in the second row: its line/arc path falls back to structural equality, which would answer a spline pair wrongly rather than not at all.

To work around the second row, sample the curve — listPoints then the ordinary core.math.vec3 operations — or read a spline brep edge exactly with core.geom.query.brep.getEdgeCurve, which returns its degree, control points and knots.

The same refusal governs the derive-new writes in core.geom.update.curve: extend, split, trim and offset refuse a spline; reverse works.

Types

`PluginGeomQueryCurveGetStartPointArgs`

Arguments for getStartPoint, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query

`PluginGeomQueryCurveGetEndPointArgs`

Arguments for getEndPoint, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query

`PluginGeomQueryCurveGetMidPointArgs`

Arguments for getMidPoint, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query

`PluginGeomQueryCurveGetLengthArgs`

Arguments for getLength, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query

`PluginGeomQueryCurveGetChordLengthArgs`

Arguments for getChordLength, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query

`PluginGeomQueryCurveGetTangentArgs`

Arguments for getTangent, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`point`	`Vec3Handle`	Point on the curve

`PluginGeomQueryCurveGetNormalArgs`

Arguments for getNormal, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`point`	`Vec3Handle`	Point on the curve

`PluginGeomQueryCurveGetNearestPointArgs`

Arguments for getNearestPoint, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`point`	`Vec3Handle`	The reference point

`PluginGeomQueryCurveGetProjectionArgs`

Arguments for getProjection, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to project onto
`point`	`Vec3Handle`	The point to project

`PluginGeomQueryCurveGetPointAtDistanceArgs`

Arguments for getPointAtDistance, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`referencePoint`	`Vec3Handle`	Point on the curve to measure from
`distance`	`number`	Distance along the curve from the reference point
`forward`	`boolean` (optional, default `true`)	Direction along the curve

`PluginGeomQueryCurveGetParameterAtPointArgs`

Arguments for getParameterAtPoint, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`point`	`Vec3Handle`	Point on the curve

`PluginGeomQueryCurveGetCurvatureArgs`

Arguments for getCurvature, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`point`	`Vec3Handle`	Point on the curve

`PluginGeomQueryCurveGetDistanceToPointArgs`

Arguments for getDistanceToPoint, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`point`	`Vec3Handle`	The point to measure from

`PluginGeomQueryCurveGetDistanceAlongArgs`

Arguments for getDistanceAlong, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`pointA`	`Vec3Handle`	First point on the curve
`pointB`	`Vec3Handle`	Second point on the curve

`PluginGeomQueryCurveListPointsArgs`

Arguments for listPoints, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to sample
`resolution`	`number` (optional, default `20`)	Number of samples for arcs; ignored for lines

`PluginGeomQueryCurveListSubdivisionsArgs`

Arguments for listSubdivisions, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to subdivide
`segments`	`number`	Number of equal segments to divide the curve into

`PluginGeomQueryCurveIsLinearArgs`

Arguments for isLinear, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query

`PluginGeomQueryCurveIsOnCurveArgs`

Arguments for isOnCurve, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`point`	`Vec3Handle`	The point to test
`threshold`	`number` (optional, defaults to the engine default)	Distance tolerance

`PluginGeomQueryCurveHasPointArgs`

Arguments for hasPoint, in positional order.

Parameter	Type	Description
`curve`	`CurveHandle`	The curve to query
`point`	`Vec3Handle`	The point to test
`includeEndPoints`	`boolean` (optional, default `true`)	Count endpoints as contained

`PluginGeomQueryCurveIsEqualArgs`

Arguments for isEqual, in positional order.

Parameter	Type	Description
`curveA`	`CurveHandle`	First curve
`curveB`	`CurveHandle`	Second curve

`PluginGeomQueryCurveIsOverlappingArgs`

Arguments for isOverlapping, in positional order.

Parameter	Type	Description
`curveA`	`CurveHandle`	First curve
`curveB`	`CurveHandle`	Second curve
`includeEndPoints`	`boolean` (optional, default `false`)	Count endpoint contact as overlap

`PluginGeomQueryCurveGetCommonPartArgs`

Arguments for getCommonPart, in positional order.

Parameter	Type	Description
`curveA`	`CurveHandle`	First curve
`curveB`	`CurveHandle`	Second curve

`PluginGeomQueryCurveListIntersectionsArgs`

Arguments for listIntersections, in positional order.

Parameter	Type	Description
`curveA`	`CurveHandle`	First curve
`curveB`	`CurveHandle`	Second curve
`boundedA`	`boolean` (optional, default `true`)	Bound intersections to `curveA`'s extent
`boundedB`	`boolean` (optional, default `true`)	Bound intersections to `curveB`'s extent

`PluginGeomQueryCurveGetMergedCurveArgs`

Arguments for getMergedCurve, in positional order.

Parameter	Type	Description
`curveA`	`CurveHandle`	First curve
`curveB`	`CurveHandle`	Second curve

`PluginGeomQueryCurveIsContinuousArgs`

Arguments for isContinuous, in positional order.

Parameter	Type	Description
`curveA`	`CurveHandle`	First curve
`curveB`	`CurveHandle`	Second curve

`PluginGeomQueryCurveIsParallelArgs`

Arguments for isParallel, in positional order.

Parameter	Type	Description
`lineA`	`LineHandle`	First line
`lineB`	`LineHandle`	Second line
`tolerance`	`number` (optional, defaults to the engine default)	Angular tolerance

`PluginGeomQueryCurveGetShortestGapArgs`

Arguments for getShortestGap, in positional order.

Parameter	Type	Description
`curveA`	`CurveHandle`	First curve
`curveB`	`CurveHandle`	Second curve
`includeEndPoints`	`boolean` (optional, default `false`)	Include endpoints when measuring

`PluginGeomQueryCurveGetDistanceBetweenArgs`

Arguments for getDistanceBetween, in positional order.

Parameter	Type	Description
`lineA`	`LineHandle`	First line
`lineB`	`LineHandle`	Second line

Functions

`getStartPoint(curve)`

Get the start point of a curve.

Parameters:
- curve: CurveHandle — The curve to query
Returns: Vec3Components — The start point

const start = await snaptrude.core.geom.query.curve.getStartPoint(curve);
console.log(start); // { x, y, z }

`getEndPoint(curve)`

Get the end point of a curve.

Parameters:
- curve: CurveHandle — The curve to query
Returns: Vec3Components — The end point

`getMidPoint(curve)`

Get the mid point of a curve.

Parameters:
- curve: CurveHandle — The curve to query
Returns: Vec3Components — The mid point

`getLength(curve)`

Get the arc-length of a curve.

Parameters:
- curve: CurveHandle — The curve to query
Returns: number — The curve length, in Snaptrude units

const length = await snaptrude.core.geom.query.curve.getLength(curve);
// Convert to a display unit with snaptrude.core.units.convert(value, from, to)

`getChordLength(curve)`

Get the straight-line chord length between a curve's endpoints.

Parameters:
- curve: CurveHandle — The curve to query
Returns: number — The chord length, in Snaptrude units

`getTangent(curve, point)`

Get the unit tangent vector of a curve at a point on it.

Parameters:
- curve: CurveHandle — The curve to query
- point: Vec3Handle — Point on the curve
Returns: Vec3Components — The tangent vector

`getNormal(curve, point)`

Get the unit normal vector of a curve at a point on it.

Parameters:
- curve: CurveHandle — The curve to query
- point: Vec3Handle — Point on the curve
Returns: Vec3Components — The normal vector

`getNearestPoint(curve, point)`

Get the point on a curve nearest to an arbitrary point.

Parameters:
- curve: CurveHandle — The curve to query
- point: Vec3Handle — The reference point
Returns: Vec3Components — The nearest point on the curve

const p = await snaptrude.core.math.vec3.new(2, 0, 5);
const nearest = await snaptrude.core.geom.query.curve.getNearestPoint(curve, p);

`getProjection(curve, point)`

Project a point onto a curve.

Parameters:
- curve: CurveHandle — The curve to project onto
- point: Vec3Handle — The point to project
Returns: Vec3Components — The projected point

`getPointAtDistance(curve, referencePoint, distance, forward?)`

Get the point at a given distance along a curve from a reference point.

Parameters:
- curve: CurveHandle — The curve to query
- referencePoint: Vec3Handle — Point on the curve to measure from
- distance: number — Distance along the curve from the reference point
- forward: boolean (optional, default true) — Direction along the curve
Returns: Vec3Components — The resulting point

`getParameterAtPoint(curve, point)`

Get the curve parameter corresponding to a point on the curve.

Parameters:
- curve: CurveHandle — The curve to query
- point: Vec3Handle — Point on the curve
Returns: number — The parameter

`getCurvature(curve, point)`

Get the curvature of a curve at a point on it.

Parameters:
- curve: CurveHandle — The curve to query
- point: Vec3Handle — Point on the curve
Returns: number — The curvature

`getDistanceToPoint(curve, point)`

Get the shortest distance from an arbitrary point to a curve.

Parameters:
- curve: CurveHandle — The curve to query
- point: Vec3Handle — The point to measure from
Returns: number — The distance, in Snaptrude units

`getDistanceAlong(curve, pointA, pointB)`

Get the arc-length distance along a curve between two points on it.

Parameters:
- curve: CurveHandle — The curve to query
- pointA: Vec3Handle — First point on the curve
- pointB: Vec3Handle — Second point on the curve
Returns: number — The distance along the curve, in Snaptrude units

`listPoints(curve, resolution?)`

List sampled points along a curve.

Parameters:
- curve: CurveHandle — The curve to sample
- resolution: number (optional, default 20) — Number of samples for arcs; ignored for lines
Returns: Vec3Components[] — The sampled points

`listSubdivisions(curve, segments)`

List the points produced by subdividing a curve into equal segments.

Parameters:
- curve: CurveHandle — The curve to subdivide
- segments: number — Number of equal segments to divide the curve into
Returns: Vec3Components[] — The subdivision points

// Divide an arc into 4 equal segments
const points = await snaptrude.core.geom.query.curve.listSubdivisions(arc, 4);

`isLinear(curve)`

Test whether a curve is a straight line.

Parameters:
- curve: CurveHandle — The curve to query
Returns: boolean — true if the curve is linear, otherwise false

`isOnCurve(curve, point, threshold?)`

Test whether a point lies on a curve within an optional threshold.

Parameters:
- curve: CurveHandle — The curve to query
- point: Vec3Handle — The point to test
- threshold: number (optional, defaults to the engine default) — Distance tolerance
Returns: boolean — true if the point is on the curve, otherwise false

`hasPoint(curve, point, includeEndPoints?)`

Test whether a curve contains a point, optionally including its endpoints.

Parameters:
- curve: CurveHandle — The curve to query
- point: Vec3Handle — The point to test
- includeEndPoints: boolean (optional, default true) — Count endpoints as contained
Returns: boolean — true if the curve contains the point, otherwise false

`isEqual(curveA, curveB)`

Test whether two curves are geometrically equal.

Parameters:
- curveA: CurveHandle — First curve
- curveB: CurveHandle — Second curve
Returns: boolean — true if the curves are equal, otherwise false

`isOverlapping(curveA, curveB, includeEndPoints?)`

Test whether two curves overlap (share a collinear/concentric span), optionally including their endpoints.

Parameters:
- curveA: CurveHandle — First curve
- curveB: CurveHandle — Second curve
- includeEndPoints: boolean (optional, default false) — Count endpoint contact as overlap
Returns: boolean — true if the curves overlap, otherwise false

`getCommonPart(curveA, curveB)`

Get the common (overlapping) part of two curves.

Parameters:
- curveA: CurveHandle — First curve
- curveB: CurveHandle — Second curve
Returns: CurveHandle | null — The common part, or null if there is none

`listIntersections(curveA, curveB, boundedA?, boundedB?)`

List the intersection points between two curves.

Parameters:
- curveA: CurveHandle — First curve
- curveB: CurveHandle — Second curve
- boundedA: boolean (optional, default true) — Bound intersections to curveA's extent
- boundedB: boolean (optional, default true) — Bound intersections to curveB's extent
Returns: Vec3Components[] — The intersection points

const hits = await snaptrude.core.geom.query.curve.listIntersections(curveA, curveB);
if (hits.length > 0) {
  console.log("first intersection", hits[0]);
}

`getMergedCurve(curveA, curveB)`

Merge two curves into a single curve when they are mergeable.

Parameters:
- curveA: CurveHandle — First curve
- curveB: CurveHandle — Second curve
Returns: CurveHandle | null — The merged curve, or null if they cannot be merged

`isContinuous(curveA, curveB)`

Test whether two curves are continuous (share an endpoint without a gap).

Parameters:
- curveA: CurveHandle — First curve
- curveB: CurveHandle — Second curve
Returns: boolean — true if the curves are continuous, otherwise false

`isParallel(lineA, lineB, tolerance?)`

Test whether two lines are parallel within an optional tolerance.

Parameters:
- lineA: LineHandle — First line
- lineB: LineHandle — Second line
- tolerance: number (optional, defaults to the engine default) — Angular tolerance
Returns: boolean — true if the lines are parallel, otherwise false

`getShortestGap(curveA, curveB, includeEndPoints?)`

Get the shortest gap between two curves, optionally including their endpoints.

Parameters:
- curveA: CurveHandle — First curve
- curveB: CurveHandle — Second curve
- includeEndPoints: boolean (optional, default false) — Include endpoints when measuring
Returns: number — The shortest gap, in Snaptrude units

`getDistanceBetween(lineA, lineB)`

Get the perpendicular distance between two parallel lines.

Parameters:
- lineA: LineHandle — First line
- lineB: LineHandle — Second line
Returns: number — The distance between the lines, in Snaptrude units

Errors

Failed calls reject with a typed PluginError — see Error Handling. Conditions specific to this namespace:

Code	Thrown by	When	`details`
`HANDLE_INVALID`	all methods	A curve or point handle is invalid, stale, or foreign	—
`PRECONDITION_FAILED`	every not yet member (see Splines)	The curve is a spline and that read is not backed by spline math yet. `hint`: sample it via `listPoints` + `core.math.vec3`, or read the exact poles and knots with `core.geom.query.brep.getEdgeCurve`	—

Beyond handle resolution and the spline table these reads are total — relationship methods signal "no result" by returning null, not by throwing.

Math

Storeys

Geometry

Query

Update

I/O

Query: Curve ​

Splines ​

Types ​

PluginGeomQueryCurveGetStartPointArgs ​

PluginGeomQueryCurveGetEndPointArgs ​

PluginGeomQueryCurveGetMidPointArgs ​

PluginGeomQueryCurveGetLengthArgs ​

PluginGeomQueryCurveGetChordLengthArgs ​

PluginGeomQueryCurveGetTangentArgs ​

PluginGeomQueryCurveGetNormalArgs ​

PluginGeomQueryCurveGetNearestPointArgs ​

PluginGeomQueryCurveGetProjectionArgs ​

PluginGeomQueryCurveGetPointAtDistanceArgs ​

PluginGeomQueryCurveGetParameterAtPointArgs ​

PluginGeomQueryCurveGetCurvatureArgs ​

PluginGeomQueryCurveGetDistanceToPointArgs ​

PluginGeomQueryCurveGetDistanceAlongArgs ​

PluginGeomQueryCurveListPointsArgs ​

PluginGeomQueryCurveListSubdivisionsArgs ​

PluginGeomQueryCurveIsLinearArgs ​

PluginGeomQueryCurveIsOnCurveArgs ​

PluginGeomQueryCurveHasPointArgs ​

PluginGeomQueryCurveIsEqualArgs ​

PluginGeomQueryCurveIsOverlappingArgs ​

PluginGeomQueryCurveGetCommonPartArgs ​

PluginGeomQueryCurveListIntersectionsArgs ​

PluginGeomQueryCurveGetMergedCurveArgs ​

PluginGeomQueryCurveIsContinuousArgs ​

PluginGeomQueryCurveIsParallelArgs ​

PluginGeomQueryCurveGetShortestGapArgs ​

PluginGeomQueryCurveGetDistanceBetweenArgs ​

Functions ​

getStartPoint(curve) ​

getEndPoint(curve) ​

getMidPoint(curve) ​

getLength(curve) ​

getChordLength(curve) ​

getTangent(curve, point) ​

getNormal(curve, point) ​

getNearestPoint(curve, point) ​

getProjection(curve, point) ​

getPointAtDistance(curve, referencePoint, distance, forward?) ​

getParameterAtPoint(curve, point) ​

getCurvature(curve, point) ​

getDistanceToPoint(curve, point) ​

getDistanceAlong(curve, pointA, pointB) ​

listPoints(curve, resolution?) ​

listSubdivisions(curve, segments) ​

isLinear(curve) ​

isOnCurve(curve, point, threshold?) ​

hasPoint(curve, point, includeEndPoints?) ​

isEqual(curveA, curveB) ​

isOverlapping(curveA, curveB, includeEndPoints?) ​

getCommonPart(curveA, curveB) ​

listIntersections(curveA, curveB, boundedA?, boundedB?) ​

getMergedCurve(curveA, curveB) ​

isContinuous(curveA, curveB) ​

isParallel(lineA, lineB, tolerance?) ​

getShortestGap(curveA, curveB, includeEndPoints?) ​

getDistanceBetween(lineA, lineB) ​

Errors ​