Class BezierPath

Classdesc

A BezierPath class.

This was refactored from an older project.

Requires

Bounds

Requires

Vertex

Requires

CubicBezierCurve

Requires

XYCoords

Requires

SVGSerializable

Requires

UID

Requires

UIDGenerator

Implements

SVGSerializable

Index

Constructors

constructor

Properties

END_CONTROL_POINT END_POINT START_CONTROL_POINT START_POINT adjustCircular bezierCurves className isDestroyed pathPoints totalArcLength uid END_CONTROL_POINT END_POINT START_CONTROL_POINT START_POINT

Constructors

`Private` constructor

new BezierPath(): BezierPath
The constructor.

This constructor expects a sequence of path points and will approximate the location of control points by picking some between the points.
You should consider just constructing empty paths and then add more curves later using the addCurve() function.

Returns BezierPath
Name
BezierPath
- Defined in src/ts/BezierPath.ts:144

Properties

END_CONTROL_POINT

END_CONTROL_POINT: number = 2

Constant

END_POINT

END_POINT: number = 3

Constant

START_CONTROL_POINT

START_CONTROL_POINT: number = 1

Constant

START_POINT

START_POINT: number = 0

Constant

adjustCircular

adjustCircular: boolean

Set this flag to true if you want the first point and last point of the path to be auto adjusted, too.

Member

Memberof

BezierPath

Instance

bezierCurves

bezierCurves: CubicBezierCurve[]

Member

Memberof

BezierPath

Instance

`Readonly` className

className: string = "BezierPath"

Required to generate proper CSS classes and other class related IDs.

isDestroyed

isDestroyed: boolean

Member

Memberof

BezierPath

Instance

pathPoints

pathPoints: Vertex[]

Member

Memberof

BezierPath

Instance

totalArcLength

totalArcLength: number

Member

Memberof

BezierPath

Instance

`Readonly` uid

uid: string

The UID of this drawable object.

Member

Memberof

BezierCurve

Instance

`Static` END_CONTROL_POINT

END_CONTROL_POINT: number = 2

Constant

`Static` END_POINT

END_POINT: number = 3

Constant

`Static` START_CONTROL_POINT

START_CONTROL_POINT: number = 1

Constant

`Static` START_POINT

START_POINT: number = 0

Constant

Methods

addCurve

addCurve(curve): void
Add a cubic bezier curve to the end of this path.
Parameters
- curve: CubicBezierCurve
  The curve to be added to the end of the path.
Returns void
Method
addCurve

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:167

`Private` adjustPredecessorControlPoint

adjustPredecessorControlPoint(curveIndex, obtainHandleLength, updateArcLengths): void
Private
This helper function adjusts the given point's predecessor's control point.
Parameters
- curveIndex: number
  The curve index to move a point from.
- obtainHandleLength: boolean
  Moves the point with keeping the original handle length.
- updateArcLengths: boolean
Returns void
Method
adjustPredecessorControlPoint

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:721

`Private` adjustSuccessorControlPoint

adjustSuccessorControlPoint(curveIndex, obtainHandleLength, updateArcLengths): void
Private
This helper function adjusts the given point's successor's control point.
Parameters
- curveIndex: number
  The curve index to move a point from.
- obtainHandleLength: boolean
  Moves the point with keeping the original handle length.
- updateArcLengths: boolean
Returns void
Method
adjustSuccessorControlPoint

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:752

clone

clone(): BezierPath
Clone this BezierPath (deep clone).

Returns BezierPath
Method
clone

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:907

destroy

destroy(): void
This function should invalidate any installed listeners and invalidate this object. After calling this function the object might not hold valid data any more and should not be used.

Returns void
Method
destroy

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:949

equals

equals(path): boolean
Compare this and the passed Bézier path.
Parameters
- path: BezierPath
  The pass to compare with.
Returns boolean
Method
equals

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:928

getBounds

getBounds(): Bounds
Get the bounds of this Bézier path.

Note the the curves' underlyung segment buffers are used to determine the bounds. The more elements the segment buffers have, the more precise the returned bounds will be.

Returns Bounds
The bounds of this Bézier path.
- Defined in src/ts/BezierPath.ts:827

getClosestT

getClosestT(p): number
Get the 't' position on this curve with the minimal distance to point p.
Parameters
- p: Vertex
  The point to find the closest curve point for.
Returns number
A value t with 0.0 <= t <= 1.0.
- Defined in src/ts/BezierPath.ts:411

getCurveAt

getCurveAt(curveIndex): CubicBezierCurve
Get the cubic bezier curve at the given index.
Parameters
- curveIndex: number
Returns CubicBezierCurve
The curve at the specified index.

Method
getCurveAt

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:304

getCurveCount

getCurveCount(): number
Get the number of curves in this path.

Returns number
The number of curves in this path.

Method
getCurveCount

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:291

getEvenDistributionVertices

getEvenDistributionVertices(pointCount): Vertex[]
Get n 'equally' distributed vertices along this Bézier path.

As the changing curvature of the B slines makes prediction of distances difficult, the returned vertices' distances are only relatively equal:
- the distance grows where curvature is large.
- the distance shrinks where curvature is small.
Only the distance mean of all consecutive is 1/n-th of the total arc length.

Usually this approximation is good enough for most use cases.
Parameters
- pointCount: number
  (must be at least 2) The number of desired points (start and end point included).
Returns Vertex[]
- Defined in src/ts/BezierPath.ts:856

getLength

getLength(): number
Get the total length of this path.

Note that the returned value comes from the curve buffer. Unregistered changes to the curve points will result in invalid path length values.

Returns number
The (buffered) length of the path.

Method
getLength

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:258

getPerpendicular

getPerpendicular(u): Vertex
Get the perpendicular of the bézier path at the given relative path location.

Note that the returned vector is not normalized.
Parameters
- u: number
  The relative path position:
```
0 <= u <= getLength()
```
Returns Vertex
The perpendicluar vector at the relative path position.

Method
getPerpendicular

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:548

getPerpendicularAt

getPerpendicularAt(t): Vertex
Get the perpendicular of the bézier path at the given absolute path location (fraction).

Note that the returned vector is not normalized.
Parameters
- t: number
  The absolute path position:
```
0.0 <= t <= 1.0
```
Returns Vertex
The perpendicluar vector at the absolute path position.

Method
getPerpendicularAt

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:533

getPoint

getPoint(u): Vertex
Get the point on the bézier path at the given relative path location.
Parameters
- u: number
  The relative path position:
```
0 <= u <= this.getLength()
```
Returns Vertex
The point at the relative path position.

Method
getPoint

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:443

getPointAt

getPointAt(t): Vertex
Get the point on the bézier path at the given path fraction.
Parameters
- t: number
  The absolute path position:
```
0.0 <= t <= 1.0
```
Returns Vertex
The point at the absolute path position.

Method
getPointAt

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:474

getSubPathAt

getSubPathAt(startT, endT): BezierPath
Get a specific sub path from this path. The start and end position are specified by ratio number in [0..1].

0.0 is at the beginning of the path. 1.0 is at the end of the path.

Values below 0 or beyond 1 are cropped down to the [0..1] interval.

startT > endT is allowed, the returned sub path will have inverse direction then.
Parameters
- startT: number
  The start position of the sub path.
- endT: number
  The end position of the sub path.
Returns BezierPath
The desired sub path in the bounds [startT..endT].

Method
getSubPathAt

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:604

getTangent

getTangent(u): Vertex
Get the tangent of the bézier path at the given path location.

Note that the returned vector is not normalized.
Parameters
- u: number
  The relative path position:
```
0 <= u <= getLength()
```
Returns Vertex
The tangent vector at the relative path position.

Method
getTangent

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:504

getTangentAt

getTangentAt(t): Vertex
Get the tangent of the bézier path at the given path fraction.

Note that the returned vector is not normalized.
Parameters
- t: number
  The absolute path position:
```
0.0 <= t <= 1.0
```
Returns Vertex
The tangent vector at the absolute path position.

Method
getTangentAt

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:489

locateCurveByEndControlPoint

locateCurveByEndControlPoint(point): number
Parameters
- point: Vertex
Returns number
- Defined in src/ts/BezierPath.ts:239

locateCurveByEndPoint

locateCurveByEndPoint(point): number
Locate the curve with the given end point (function returns the index).
Parameters
- point: Vertex
  The (curve end-) point to look for.
Returns number
The curve index or -1 if curve (end-) point not found

Method
locateCurveByEndPoint

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:208

locateCurveByStartControlPoint

locateCurveByStartControlPoint(point): number
Locate the curve with the given start point (function returns the index).
Parameters
- point: Vertex
  The (curve endt-) point to look for.
Returns number
The curve index or -1 if curve (end-) point not found

Method
locateCurveByStartControlPoint

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:225

locateCurveByStartPoint

locateCurveByStartPoint(point): number
Locate the curve with the given start point (function returns the index).
Parameters
- point: Vertex
  The (curve start-) point to look for.
Returns number
The curve index or -1 if curve (start-) point not found

Method
locateCurveByStartPoint

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:191

moveCurvePoint

moveCurvePoint(curveIndex, pointID, moveAmount): void
This function moves the addressed curve point (or control point) with keeping up the path's curve integrity.

Thus is done by moving neighbour- and control- points as needed.
Parameters
- curveIndex: number
  The curve index to move a point from.
- pointID: number
  One of the curve's four point IDs (START_POINT, START_CONTROL_POINT, END_CONTRO_POINT or END_POINT).
- moveAmount: XYCoords
  The amount to move the addressed vertex by.
Returns void
Method
moveCurvePoint

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:661

rotate

rotate(angle, center): void
Rotate the whole bezier path around a point..
Parameters
- angle: number
  The angle to rotate this path by.
- center: Vertex
  The rotation center.
Returns void
Method
rotate

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:388

scale

scale(anchor, scaleFactor): BezierPath
Scale the whole bezier path by the given uniform factor.
Parameters
- anchor: Vertex
  The scale origin to scale from.
- scaleFactor: number
  The scalar to be multiplied with.
Returns BezierPath
this for chaining.

Method
scale

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:344

scaleXY

scaleXY(scaleFactors, anchor?): BezierPath
Scale the whole bezier path by the given (x,y)-factors.
Parameters
- scaleFactors: XYCoords
- Optional anchor: XYCoords
  The scale origin to scale from.
Returns BezierPath
this for chaining.

Method
scale

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:358

toJSON

toJSON(prettyFormat): string
Create a JSON string representation of this bézier curve.
Parameters
- prettyFormat: boolean
  If true then the function will add line breaks.
Returns string
The JSON string.

Method
toJSON

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:1001

toPathPoints

toPathPoints(): XYCoords[]
Convert this path to an array of path points that can be drawn by the default DrawLib implementations.

Returns XYCoords[]
Method
toPathPoints

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:965

toReducedListRepresentation

toReducedListRepresentation(digits): string
This function converts the bezier path into a string containing integer values only. The points' float values are rounded to 1 digit after the comma.

The returned string represents a JSON array (with leading '[' and trailing ']', the separator is ',').
Parameters
- digits: number
  The number of digits to be used after the comma '.'.
Returns string
The reduced list representation of this path.

Method
toReducedListRepresentation

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:1111

translate

translate(amount): BezierPath
Move the whole bezier path by the given (x,y)-amount.
Parameters
- amount: Vertex
  The amount to be added (amount.x and amount.y) to each vertex of the curve.
Returns BezierPath
this for chaining

Method
translate

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:318

updateArcLengths

updateArcLengths(): void
This function is internally called whenever the curve or path configuration changed. It updates the attribute that stores the path length information.

If you perform any unregistered changes to the curve points you should call this function afterwards to update the curve buffer. Not updating may result in unexpected behavior.

Returns void
Method
updateArcLengths

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:275

`Static` `Private` _locateUIndex

_locateUIndex(path, u): {
    i: number;
    uBefore: number;
    uPart: number;
}
This is a helper function to locate the curve index for a given absolute path position u.

I decided to put this into privat scope as it is really specific. Maybe put this into a utils wrapper.

Returns:
- {number} i - the index of the containing curve.
- {number} uPart - the absolute curve length sum (length from the beginning to u, should equal u itself).
- {number} uBefore - the absolute curve length for all segments before the matched curve (usually uBefore <= uPart).
Parameters
- path: BezierPath
- u: number
Returns {
    i: number;
    uBefore: number;
    uPart: number;
}
- i: number
- uBefore: number
- uPart: number
- Defined in src/ts/BezierPath.ts:574

`Static` `Private` adjustNeighbourControlPoint

adjustNeighbourControlPoint(_mainCurve, neighbourCurve, mainPoint, mainControlPoint, neighbourPoint, neighbourControlPoint, obtainHandleLengths, _updateArcLengths): void
Private
This helper function adjusts the given point's successor's control point.
Parameters
- _mainCurve: CubicBezierCurve
- neighbourCurve: CubicBezierCurve
- mainPoint: Vertex
- mainControlPoint: Vertex
- neighbourPoint: Vertex
- neighbourControlPoint: Vertex
- obtainHandleLengths: boolean
- _updateArcLengths: boolean
Returns void
Method
adjustNeighbourControlPoint

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:786

`Static` fromArray

fromArray(obj): BezierPath
Create a BezierPath instance from the given array.
Parameters
- obj: any
Returns BezierPath
The bezier path instance retrieved from the array data.

Method
fromArray

Throw
An error if the array does not contain proper bezier path data.

Static
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:1056

`Static` fromCurve

fromCurve(curve): BezierPath
Construct a new path with a single curve. Adding more curves is always possible.
Parameters
- curve: CubicBezierCurve
  The curve to construct a new path from.
Returns BezierPath
The constructed bezier path instance.

Method
fromCurve

Static
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:1040

`Static` fromJSON

fromJSON(jsonString): BezierPath
Parse a BezierPath from the given JSON string.
Parameters
- jsonString: string
  The string with the JSON data.
Returns BezierPath
The parsed bezier path instance.

Method
fromJSON

Throw
An error if the string is not JSON or does not contain a bezier path object.

Static
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:1026

`Static` fromReducedList

fromReducedList(pointArray, adjustCircular?): BezierPath
Convert a reduced list representation (array of numeric coordinates) to a BezierPath instance.

The array's length must be 6*n + 2:
- [sx, sy, scx, scy, ecx, ecy, ... , ex, ey ] | | | | +--- sequence of curves --------+ +-end-+
Parameters
- pointArray: number[]
- Optional adjustCircular: boolean
Returns BezierPath
BezierPath
- Defined in src/ts/BezierPath.ts:1184

`Static` fromReducedListRepresentation

fromReducedListRepresentation(listJSON, adjustCircular?): BezierPath
Parse a BezierPath instance from the reduced list representation.

The passed string must represent a JSON array containing numbers only.
Parameters
- listJSON: string
  The number of digits to be used after the floating point.
- Optional adjustCircular: boolean
Returns BezierPath
The bezier path instance retrieved from the string.

Method
fromReducedListRepresentation

Throw
An error if the string is malformed.

Instance
Memberof
BezierPath
- Defined in src/ts/BezierPath.ts:1156

Class BezierPath

Classdesc

Requires

Requires

Requires

Requires

Requires

Requires

Requires

Implements

Index

Constructors

Properties

Methods

Constructors

Private constructor

Returns BezierPath

Name

Properties

END_CONTROL_POINT

Constant

END_POINT

Constant

START_CONTROL_POINT

Constant

START_POINT

Constant

adjustCircular

Member

Memberof

Instance

bezierCurves

Member

Memberof

Instance

Readonly className

isDestroyed

Member

Memberof

Instance

pathPoints

Member

Memberof

Instance

totalArcLength

Member

Memberof

Instance

Readonly uid

Member

Memberof

Instance

Static END_CONTROL_POINT

Constant

Static END_POINT

Constant

Static START_CONTROL_POINT

Constant

Static START_POINT

Constant

Methods

addCurve

Parameters

Returns void

Method

Instance

Memberof

Private adjustPredecessorControlPoint

Parameters

Returns void

Method

Instance

Memberof

Private adjustSuccessorControlPoint

Parameters

Returns void

Method

Instance

Memberof

clone

`Private` constructor

`Readonly` className

`Readonly` uid

`Static` END_CONTROL_POINT

`Static` END_POINT

`Static` START_CONTROL_POINT

`Static` START_POINT

`Private` adjustPredecessorControlPoint

`Private` adjustSuccessorControlPoint