Geometric Algorithms

Point

Class/Namespace	Method	Parameters	Description
GeoPoint	add	p: GeoPoint	Add two points. Example: let p1 = new vjmap.GeoPoint(1,2); let p2 = new vjmap.GeoPoint(3, 4); p1.add(p2); // 4, 6
GeoPoint	sub	p: GeoPoint	Subtract two points
GeoPoint	multByPoint	p: GeoPoint	Multiply two points
GeoPoint	divByPoint	p: GeoPoint	Divide two points
GeoPoint	dot	p: GeoPoint	Vector dot product
GeoPoint	lerp	v: GeoPoint, alpha: number	Interpolate a new point between two points by ratio
GeoPoint	rotate	angle: number	Rotate
GeoPoint	roateAround	angle: number, p: GeoPoint	Rotate around a point.
GeoPoint	matMult	m: number[]	Multiply by a matrix
GeoPoint	unit		Unit length
GeoPoint	equals	other: GeoPoint, dotErr: number = 8	Check if equal
GeoPoint	distanceTo	p: GeoPoint	Distance between two points
GeoPoint	angle		Angle
GeoPoint	angleTo	p: GeoPoint	Angle to a point
GeoPoint	angleWith	p: GeoPoint	interiorAngle to a point
GeoPoint	angleWithSep	p: GeoPoint	interiorAngle to a point
GeoPoint	transform	basePt: GeoPoint, destPt: GeoPoint, scale?:number, angle?: number	Scale, rotate, and translate a point around a base point.

Bounding Box

Class/Namespace	Method	Parameters	Description
GeoBounds	center		Get center point. Example: let bounds = new vjmap.GeoBounds([0,10], [10, 50]); let c = bounds.center(); // [5, 30]
GeoBounds	square	isLatlng?: boolean, isMinValue?: boolean	Make square with equal width and height
GeoBounds	width		Get width
GeoBounds	height		Get height
GeoBounds	scale	ratio: number, origin?: GeoPoint | null	Scale to produce a new GeoBounds.
GeoBounds	scaleXY	ratioX: number, ratioY: number, origin?: GeoPoint | null	Scale by X/Y ratio to produce a new GeoBounds.
GeoBounds	translate	dx: number, dy: number	Translate bounding box
GeoBounds	update	vertices: GeoPoint[]	Update bounding box
GeoBounds	updateByBounds	bounds: GeoBounds[] | GeoBounds	Update bounding box from child bounds
GeoBounds	intersect	b: GeoBounds	Intersection of two bounding boxes
GeoBounds	union	bound: GeoBounds	Union of multiple bounding boxes
GeoBounds	isIntersect	bound: GeoBounds	Check if intersects with another bounding box
GeoBounds	isContains	bound: GeoBounds	Check if one bounding box contains another
GeoBounds	contains	point: GeoPoint	Check if point is inside bounding box
GeoBounds	closestPoint	testPoint: GeoPoint, includeInterior: boolean = true	Find the closest point on the bounding box and return it.

Line

Class/Namespace	Method	Parameters	Description
vjmap	pointToSegmentDistance	p: GeoPoint, p1: GeoPoint, p2: GeoPoint	Distance from point to segment. Example: vjmap.pointToSegmentDistance(vjmap.geoPoint([3, 2]), vjmap.geoPoint([0,0]), vjmap.geoPoint([0, 10])) // 3
vjmap	simplify	points: GeoPoint[], tolerance?: number	Simplify point coordinates
vjmap	closestPointOnSegment	p: GeoPoint, p1: GeoPoint, p2: GeoPoint	Closest point on segment to a point
vjmap	closestPointOnPolyline	p: GeoPoint, points: GeoPoint[]	Closest point on polyline to a point
vjmap	closestPointOnPolylines	p: GeoPoint, lines: GeoPoint[][]	Closest point on multiple lines to a point
vjmap	segmentIntersect	x1,y1,x2,y2,x3,y3,x4,y4	Segment intersection
vjmap	lineSplit	line: GeoPoint[], splitLine: GeoPoint[], dotErr?: number	Split a line by another line into multiple segments, returns new segments
vjmap	multiLineSplit	lines: GeoPoint[][], dotErr?: number	Split multiple lines by their intersections, returns all segments after splitting. Ensure each segment does not self-intersect
vjmap	clipSegment	a: GeoPoint, b: GeoPoint, bounds: GeoBounds	Clip segment by bounds
vjmap	interpolatePointsByRatio	points: GeoPointLike[], ratio: number, isLngLat: boolean = false	Get point coordinates from coordinate sequence by ratio (0-1)
vjmap	interpolateLineRange	points, number, isLngLat, offsetDist, minGap, includeSrcPoint	Vertices of (poly)line to interpolate (input must be lon/lat).
vjmap.Math2D	dist	ax,ay, bx, by	Calculate distance between two points
vjmap.Math2D	lineDist	pts: GeoPointLike[]	Calculate line length
vjmap.Math2D	distToSegmentSquared	px, py, l0x, l0y, l1x, l1y	Squared distance between point and 2D segment.
vjmap.Math2D	intersectLineAndCircle	xLine1, yLine1, xLine2, yLine2, radius, xCenter, yCenter	Intersection of line and circle
vjmap.Math2D	lineDist	pts: GeoPointLike[]	Calculate line length

Polygon

Class/Namespace	Method	Parameters	Description
vjmap	calcPolygonArea	points: GeoPoint[]	Calculate polygon area. Example: vjmap.calcPolygonArea([vjmap.geoPoint([0, 0]),vjmap.geoPoint([5, 5]),vjmap.geoPoint([10, 0])]) // 25
vjmap	clipPolygon	points: GeoPoint[], bounds: GeoBounds	Clip polygon by bounds
vjmap	bufferConvexPolygon	ring: GeoPoint[], buffer: number	Take a convex ring and expand it outward by applying a buffer. Assumes ring is clockwise wound.
vjmap	polygonIsClockwise	points: GeoPoint[]	Determine if polygon is clockwise using Green's formula
vjmap	polygonCentroid	points: GeoPoint[]	Calculate polygon centroid from coordinate list
vjmap	isPointInPolygon	pos: GeoPoint, polygon: GeoPoint[]	Check if point is inside polygon.
vjmap	polylineMarginToPolygon	pts: GeoPointLike[],options	Expand polyline outward into a polygon.
vjmap	createObjectPolygonUtil		Create a polygon geometry utility object for difference, union, intersection, etc.

Circle/Ellipse

Class/Namespace	Method	Parameters	Description
vjmap	getCirclePolygonCoordinates	center,radius,points,startAngle,endAngle	Get discretized polygon points for circle or arc
vjmap	getCircleFeature	center,radius,points,startAngle,endAngle	Get discretized polygon as GeoJSON for circle or arc
vjmap	getEllipsePolygonCoordinates	Same as above, majorAxisRadius, minorAxisRadius	Get discretized polygon points for ellipse or elliptic arc
vjmap	getEllipseFeature	Same as above, majorAxisRadius, minorAxisRadius	Get discretized polygon as GeoJSON for ellipse or elliptic arc

Curve

Class/Namespace	Method	Parameters	Description
vjmap	bezierCurveToPolyline	bezierCurve,precision, recursiveCount	Convert bezierCurve to polyline
vjmap	getBezierCurveLength	bezierCurve,precision, recursiveCount	Calculate Bezier curve length
vjmap	convertBezierCurveToPolyline	bezierCurve,precision, recursiveCount	Convert Bezier curve to polyline.

Topology Graph

Class/Namespace	Method	Parameters	Description
vjmap	Graph		Find shortest path. Example: var graph = Graph().addEdge("s", "t", 10).addEdge("s", "y", 5).addEdge("s", "y", 4).addEdge("t", "y", 2).addEdge("y", "t", 3).addEdge("t", "x", 1).addEdge("y", "x", 9).addEdge("y", "z", 2).addEdge("x", "z", 4).addEdge("z", "x", 6);var res = graph.shortestPath("s", "z")
vjmap	findShortestPath	startPoint, endPoint,lines,precision,hasDirection	Generate shortest path given all routes, start point, and end point

Algorithms

Class/Namespace	Method	Parameters	Description
vjmap	coordTransfromGetFourParamter	srcArr,destArr,isSetRotateZero,isConsiderPointOrder	Get four parameters for coordinate transformation
vjmap	coordTransfromByFourParamter	pt: GeoPoint, param: {dx: number, dy: number, scale: number, rotate: number}	Coordinate transformation using four parameters
vjmap	coordTransfromByInvFourParamter	pt: GeoPoint, param: {dx: number, dy: number, scale: number, rotate: number}	Coordinate transformation using inverse four parameters
vjmap	buildTransformerMatrix3d	src: number[], dest: number[]	Perspective projection to 3D CSS matrix
vjmap	vectorContour	featureCollection: FeatureCollection,weight: string, breaks: number[],params	Generate vector contour map

Others

Class/Namespace	Method	Parameters	Description	Example
vjmap.MathUtils	equals	num1: number, num2: number, dotErr: number = 8	Check if two numbers are equal	vjmap.MathUtils.equals(0.0041, 0.0042, 3) // true
vjmap.MathUtils	lerp	v1: number, v2: number, value: number	Linear interpolation	vjmap.MathUtils.lerp(10, 20, 0.3) // 13
vjmap.MathUtils	map	val: number, inMin: number, inMax: number, outMin: number, outMax: number	Map a number from one range to another.	vjmap.MathUtils.map(5, 0, 10, 100, 200) // 150
vjmap.MathUtils	clamp	value: number, min: number, max: number	Clamp value to given range.	vjmap.MathUtils.clamp(-1, 0, 10) // 0
vjmap.MathUtils	wrap	n: number, min: number, max: number, isMin: boolean = false	Constrain n to given range via modulo, excluding minimum	vjmap.MathUtils.wrap(11, 0, 10) // 1

Geometric Model

API documentation: https://vjmap.com/docs/geomodel/ (opens new window)

Example code: https://vjmap.com/demo/#/demo/map/models/01geomodels (opens new window)