LineSegment

A 2D line segment

Index

Constructors

• constructor

Properties

• begin
• end

Accessors

• intercept
• midpoint
• slope

Methods

• below
• clip
• clone
• dir
• distanceToPoint
• findPoint
• findVectorToPoint
• flip
• getEdge
• getLength
• getPoints
• getSlope
• hasPoint
• normal
• transform

Constructors

constructor

• new LineSegment(begin: Vector, end: Vector): LineSegment

• Parameters

  • begin: Vector

    The starting point of the line segment

  • end: Vector

    The ending point of the line segment

  Returns LineSegment

Properties

publicbegin

begin: Vector

The starting point of the line segment

publicend

end: Vector

The ending point of the line segment

Accessors

publicintercept

• get intercept(): number

• Gets the Y-intercept (b) of the line. Will return (+/-)Infinity if there is no intercept.

  ---

  Returns number

publicmidpoint

• get midpoint(): Vector

• Returns the midpoint of the edge

  ---

  Returns Vector

publicslope

• get slope(): number

• Gets the raw slope (m) of the line. Will return (+/-)Infinity for vertical lines.

  ---

  Returns number

Methods

publicbelow

• below(point: Vector): boolean

• Tests if a given point is below the line, points in the normal direction above the line are considered above.

  ---

  Parameters

  • point: Vector

  Returns boolean

publicclip

• clip(sideVector: Vector, length: number, normalize?: boolean): LineSegment

• Returns the clip point

  ---

  Parameters

  • sideVector: Vector

    Vector that traces the line

  • length: number

    Length to clip along side

  • normalize: boolean = true

  Returns LineSegment

clone

• clone(dest?: LineSegment): LineSegment

• Parameters

  • optionaldest: LineSegment

  Returns LineSegment

publicdir

• dir(): Vector

• Returns Vector

publicdistanceToPoint

• distanceToPoint(point: Vector, signed?: boolean): number

• Find the perpendicular distance from the line to a point https://en.wikipedia.org/wiki/Distance_from_a_point_to_a_line

  ---

  Parameters

  • point: Vector

  • signed: boolean = false

  Returns number

publicfindPoint

• findPoint(x?: number, y?: number): Vector

• Finds a point on the line given only an X or a Y value. Given an X value, the function returns a new point with the calculated Y value and vice-versa.

  ---

  Parameters

  • x: number = null

    The known X value of the target point

  • y: number = null

    The known Y value of the target point

  Returns Vector

  A new point with the other calculated axis value

publicfindVectorToPoint

• findVectorToPoint(point: Vector): Vector

• Find the perpendicular line from the line to a point https://en.wikipedia.org/wiki/Distance_from_a_point_to_a_line (a - p) - ((a - p) * n)n a is a point on the line p is the arbitrary point above the line n is a unit vector in direction of the line

  ---

  Parameters

  • point: Vector

  Returns Vector

publicflip

• flip(): LineSegment

• Flips the direction of the line segment

  ---

  Returns LineSegment

publicgetEdge

• getEdge(): Vector

• Returns the edge of the line as vector, the length of the vector is the length of the edge

  ---

  Returns Vector

publicgetLength

• getLength(): number

• Returns the length of the line segment in pixels

  ---

  Returns number

publicgetPoints

• getPoints(): Vector[]

• Returns Vector[]

publicgetSlope

• getSlope(): Vector

• Returns the slope of the line in the form of a vector of length 1

  ---

  Returns Vector

publichasPoint

• hasPoint(x: number, y: number, threshold?: number): boolean
• hasPoint(v: Vector, threshold?: number): boolean

• Whether or not the given point lies on this line. This method is precise by default meaning the point must lie exactly on the line. Adjust threshold to loosen the strictness of the check for floating-point calculations.

  ---

  Parameters

  • x: number

  • y: number

  • optionalthreshold: number

  Returns boolean

publicnormal

• normal(): Vector

• Gets the normal of the line

  ---

  Returns Vector

transform

• transform(matrix: AffineMatrix, dest?: LineSegment): LineSegment

• Parameters

  • matrix: AffineMatrix

  • optionaldest: LineSegment

  Returns LineSegment