## Point2d Class

2D point with `x`,`y` as properties

### Methods

Name Description
constructor(x: number = 0, y: number = 0): Constructor for Point2d
addForwardLeft(tangentFraction: number, leftFraction: number, vector: Vector2d): Starting at this point, move along vector by tangentFraction of the vector length, and to the left by leftFraction of
the perpendicular vector length.

clone(): return a new Point2d with x,y coordinates from this.
crossProductToPoints(target1: XAndY, target2: XAndY): number Returns the (scalar) cross product of two points/vectors, computed from origin to target1 and target2
dotVectorsToTargets(targetA: XAndY, targetB: XAndY): number Return the dot product of vector from this to targetA and vector from this to targetB
forwardLeftInterpolate(tangentFraction: number, leftFraction: number, point: XAndY): Interpolate at tangentFraction between this instance and point.
fractionOfProjectionToLine(startPoint: Point2d, endPoint: Point2d, defaultFraction?: number): number Return the fractional coordinate of the projection of this instance x,y onto the line from startPoint to endPoint.
interpolate(fraction: number, other: XAndY, result?: Point2d): Return a point interpolated between this point and the right param.
interpolateXY(fractionX: number, fractionY: number, other: XAndY, result?: Point2d): Return a point with independent x,y fractional interpolation.
minus(vector: XAndY, result?: Point2d): Return this point minus vector
plus(vector: XAndY, result?: Point2d): Return point plus vector
plus2Scaled(vectorA: XAndY, scalarA: number, vectorB: XAndY, scalarB: number, result?: Point2d): Return point + vectorA scalarA + vectorB scalarB
plus3Scaled(vectorA: XAndY, scalarA: number, vectorB: XAndY, scalarB: number, vectorC: XAndY, scalarC: number, result?: Point2d): Return point + vectorA scalarA + vectorB scalarB + vectorC * scalarC
plusScaled(vector: XAndY, scaleFactor: number, result?: Point2d): Return point + vector * scalar
plusXY(dx: number = 0, dy: number = 0, result?: Point2d): Return point plus vector
create(x: number = 0, y: number = 0, result?: Point2d): Static Return a point (newly created unless result provided) with given x,y coordinates
createFrom(xy: XAndY | undefined, result?: Point2d): Static Create (or optionally reuse) a Point2d from another object with fields x and y
createZero(result?: Point2d): Static Create a Point2d with both coordinates zero.
fromJSON(json?: XYProps): Static Convert JSON `[1,2]` or `{x:1, y:2}` to a Point2d instance

### Inherited methods

Name Inherited from Description
distance(other: XAndY): number XY Return the distance from this point to other
distanceSquared(other: XAndY): number XY Return squared distance from this point to other
freeze(): void XY Freeze this instance (and its deep content) so it can be considered read-only
isAlmostEqual(other: XAndY, tol?: number): boolean XY Returns true if this and other have equal x,y parts within Geometry.smallMetricDistance.
isAlmostEqualMetric(other: XAndY): boolean XY returns true if x,y match `other` within metric tolerance
isAlmostEqualXY(x: number, y: number, tol?: number): boolean XY Returns true if this and other have equal x,y parts within Geometry.smallMetricDistance.
isExactEqual(other: XAndY): boolean XY returns true if the x,y components are exactly equal.
magnitude(): number XY Return the magnitude of the vector
magnitudeSquared(): number XY Return the squared magnitude of the vector.
maxAbs(): number XY Return the largest absolute value of any component
maxDiff(other: XAndY): number XY Return the largest absolute distance between corresponding components
set(x: number = 0, y: number = 0): void XY Set both x and y.
setFrom(other?: XAndY): void XY Set both x and y from other.
setFromJSON(json?: XYProps): void XY Set x and y from a JSON source such as `[1,2]` or `{x:1, y:2}`
setZero(): void XY Set both x and y to zero
toJSON(): XY return a json array `[x,y]`
toJSONXY(): XY return a json object `{x: 1, y:2}`
unitVectorTo(target: XAndY, result?: Vector2d): Vector2d | undefined XY Return a unit vector from this point to other
vectorTo(other: XAndY, result?: Vector2d): XY Return a (full length) vector from this point to other
crossProductToPoints(origin: XAndY, targetA: XAndY, targetB: XAndY): number Static XY cross product of vectors from origin to targets

### Inherited properties

Name Type Inherited from Description
isAlmostZero Accessor ReadOnly boolean XY returns true if the x,y components are both small by metric metric tolerance
x number XY x component
y number XY y component

### Defined in

Last Updated: 08 January, 2020