@urban-toolkit/autk-core

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@urban-toolkit/autk-core / TriangulatorPolylines

Class: TriangulatorPolylines

Defined in: triangulator-polylines.ts:17

Triangulates polyline features into stroked mesh geometry.

Constructors

Constructor

new TriangulatorPolylines(): TriangulatorPolylines

Returns

TriangulatorPolylines

Properties

DEFAULT_ROAD_HALF_WIDTH

readonly static DEFAULT_ROAD_HALF_WIDTH: number = 3.5

Defined in: triangulator-polylines.ts:43

Default road half-width used when no known highway tag value is available.

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offset

static offset: number = 5

Defined in: triangulator-polylines.ts:19

Default half-width, in local planar units, used when buffering source polylines.

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ROAD_HALF_WIDTH_BY_HIGHWAY

readonly static ROAD_HALF_WIDTH_BY_HIGHWAY: Record<string, number>

Defined in: triangulator-polylines.ts:22

OSM road half-widths, in local planar units, keyed by normalized highway tag value.

Methods

buildMesh()

static buildMesh(geojson, origin, resolveOffset?): [LayerGeometry[], LayerComponent[]]

Defined in: triangulator-polylines.ts:59

Builds triangulated polyline geometry for a GeoJSON feature collection.

Parameters

geojson

FeatureCollection

Source feature collection containing polyline geometries.

origin

number[]

World-space origin subtracted before converting to local planar space.

resolveOffset?

(feature, featureIndex) => number

Optional per-feature half-width resolver.

Returns

[LayerGeometry[], LayerComponent[]]

A tuple of triangulated geometry chunks and per-feature component metadata.

Throws

Never throws. Unsupported or degenerate features are skipped.

Example

const [meshes, comps] = TriangulatorPolylines.buildMesh(lineFC, origin);

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defaultOffsetResolver()

readonly static defaultOffsetResolver(_feature, _featureIndex): number

Defined in: triangulator-polylines.ts:46

Optional callback used to resolve a per-feature polyline half-width.

Parameters

_feature

Feature

_featureIndex

number

Returns

number

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geometryCollectionToPolyline()

static geometryCollectionToPolyline(feature, origin, offset, featureIndex): object[]

Defined in: triangulator-polylines.ts:178

Flattens supported children of a GeometryCollection into polyline meshes.

Parameters

feature

Feature

Source feature with GeometryCollection geometry.

origin

number[]

World-space origin subtracted before buffering.

offset

number

Polyline half-width used for planar buffering.

featureIndex

number

Index of the parent feature in the source collection.

Returns

object[]

Triangulated meshes for all supported child geometries.

Throws

Never throws. Unsupported children are skipped with a console warning.

Example

const meshes = TriangulatorPolylines.geometryCollectionToPolyline(feature, origin, 5, 0);

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lineStringToPolyline()

static lineStringToPolyline(feature, origin, offset): object[]

Defined in: triangulator-polylines.ts:121

Converts a single LineString feature into triangulated polyline mesh data.

Parameters

feature

Feature

Source feature with LineString geometry.

origin

number[]

World-space origin subtracted before buffering.

offset

number

Polyline half-width used for planar buffering.

Returns

object[]

One triangulated polygon mesh, or an empty array when buffering fails.

Throws

Never throws. Degenerate buffers return an empty array.

Example

const [mesh] = TriangulatorPolylines.lineStringToPolyline(feature, origin, 5);

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multiLineStringToPolyline()

static multiLineStringToPolyline(feature, origin, offset): object[]

Defined in: triangulator-polylines.ts:146

Converts a MultiLineString feature into triangulated polyline meshes.

Parameters

feature

Feature

Source feature with MultiLineString geometry.

origin

number[]

World-space origin subtracted before buffering.

offset

number

Polyline half-width used for planar buffering.

Returns

object[]

Triangulated meshes for each valid buffered line string.

Throws

Never throws. Invalid buffered lines are silently ignored.

Example

const meshes = TriangulatorPolylines.multiLineStringToPolyline(feature, origin, 5);

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normalizeRoadHighwayValue()

static normalizeRoadHighwayValue(highway): string | null

Defined in: triangulator-polylines.ts:221

Normalizes an OSM highway tag value for road-width lookup.

Parameters

highway

unknown

Raw highway property value (string, semicolon-delimited, or array).

Returns

string | null

Normalized highway token, or null when unavailable.

Throws

Never throws.

Example

TriangulatorPolylines.normalizeRoadHighwayValue('motorway');  // 'motorway'
TriangulatorPolylines.normalizeRoadHighwayValue('primary;secondary');  // 'primary'

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resolveRoadHalfWidth()

static resolveRoadHalfWidth(feature): number

Defined in: triangulator-polylines.ts:204

Resolves a road polyline half-width from OSM highway tag semantics.

Parameters

feature

Feature

Source road feature with highway property.

Returns

number

Polyline half-width in local planar units.

Throws

Never throws. Falls back to DEFAULT_ROAD_HALF_WIDTH.

Example

const hw = TriangulatorPolylines.resolveRoadHalfWidth(roadFeature);
// hw → 10 for motorway, 6 for primary, 3.5 for unknown