JXG.CoordsElement - Documentation

True if there the method this.updateConstraint() has been set. It is probably different from the prototype function() {return this;}. Used in updateCoords fo glider elements.

Type

Boolean

See

JXG.CoordsElement#updateCoords

Source

base/coordselement.js, line 104

needsUpdateFromParent : Boolean

Description: A JXG.CoordsElement#updateGlider call is usually followed by a general JXG.Board#update which calls JXG.CoordsElement#updateGliderFromParent. To prevent double updates, JXG.CoordsElement#needsUpdateFromParent is set to false in updateGlider() and reset to true in the following call to JXG.CoordsElement#updateGliderFromParent
Type: Boolean
Source: base/coordselement.js, line 139

(private) onPolygon : Boolean

Description: Determines whether the element slides on a polygon if point is a glider.
Type: Boolean
Default Value: false
Source: base/coordselement.js, line 112

(private) position : Number

Description: Relative position on a slide element (line, circle, curve) if element is a glider on this element.
Type: Number
Source: base/coordselement.js, line 93

slideObject : JXG.GeometryElement

Description: When used as a glider this member stores the object, where to glide on. To set the object to glide on use the method JXG.CoordsElement#makeGlider and DO NOT set this property directly as it will break the dependency tree.
Type: JXG.GeometryElement
Source: base/coordselement.js, line 121

slideObjects

Description: List of elements the element is bound to, i.e. the element glides on. Only the last entry is active. Use JXG.CoordsElement#popSlideObject to remove the currently active slideObject.
Source: base/coordselement.js, line 128

Inherited

Methods

Own

setPositionByTransform

updateGliderFromParent

Coords(digitsopt, withZopt) → {String}

Getter method for coordinates x, y and (optional) z.

Parameters

Name Type Attributes Default Description

Name	Type	Attributes	Default	Description
`digits`	Number \| String	<optional>	`'auto'`	Truncating rule for the digits in the infobox. 'auto': done automatically by `JXG.autoDigits()` 'none': no truncation number: truncate after "number digits" with `JXG.toFixed()`
`withZ`	Boolean	<optional>	`false`	If set to true the return value will be `(x \| y \| z)` instead of `(x, y)`.

digits

Number | String

'auto'

Truncating rule for the digits in the infobox.

'auto': done automatically by JXG.autoDigits()
'none': no truncation
number: truncate after "number digits" with JXG.toFixed()

withZ

Boolean

false

If set to true the return value will be (x | y | z) instead of (x, y).

Returns

User coordinates of point.

Type: String

Details

Source: base/coordselement.js, line 874

Dist(point2) → {Number}

Getter method for the distance to a second point, this is required for CAS-elements. Here, function inlining seems to be worthwile (for plotting).

Parameters

Name	Type	Description
`point2`	Point	The point to which the distance shall be calculated.

Returns

Distance in user coordinate to the given point

Type: Number

Details

Source: base/coordselement.js, line 969

X() → {Number}

Getter method for x, this is used by for CAS-points to access point coordinates.

Returns

User coordinate of point in x direction.

Type: Number

Details

Source: base/coordselement.js, line 843

(private) XEval() → {Number}

New evaluation of the function term. This is required for CAS-points: Their XTerm() method is overwritten in JXG.CoordsElement#addConstraint.

Returns

User coordinate of point in x direction.

Type: Number

Details

Source: base/coordselement.js, line 935

Y() → {Number}

Getter method for y, this is used by CAS-points to access point coordinates.

Returns

User coordinate of point in y direction.

Type: Number

Details

Source: base/coordselement.js, line 851

(private) YEval() → {Number}

New evaluation of the function term. This is required for CAS-points: Their YTerm() method is overwritten in JXG.CoordsElement#addConstraint.

Returns

User coordinate of point in y direction.

Type: Number

Details

Source: base/coordselement.js, line 947

Z() → {Number}

Getter method for z, this is used by CAS-points to access point coordinates.

Returns

User coordinate of point in z direction.

Type: Number

Details

Source: base/coordselement.js, line 859

(private) ZEval() → {Number}

New evaluation of the function term. This is required for CAS-points: Their ZTerm() method is overwritten in JXG.CoordsElement#addConstraint.

Returns

User coordinate of point in z direction.

Type: Number

Details

Source: base/coordselement.js, line 959

(private) _anim(direction, stepCount, maxRoundsopt) → {JXG.CoordsElement}

Animates a glider. Is called by the browser after startAnimation is called.

Parameters

Name	Type	Attributes	Default	Description
`direction`	Number			The direction the glider is animated.
`stepCount`	Number			The number of steps in which the parent element is divided. Must be at least 1.
`maxRounds`	Number	<optional>	`-1`	The number of rounds the glider will be animated. The glider will run infinitely if maxRounds is negative or equal to Infinity.

Returns

Reference to itself.

Type: JXG.CoordsElement

Details

See

JXG.CoordsElement#startAnimation
JXG.CoordsElement#stopAnimation

Source

base/coordselement.js, line 2411

(private) addAnchor(coordinates, isLabel)

In case there is an attribute "anchor", the element is bound to this anchor element. This is handled with this.relativeCoords. If the element is a label relativeCoords are given in scrCoords, otherwise in usrCoords.

Parameters

Name	Type	Description
`coordinates`	Array	Offset from the anchor element. These are the values for this.relativeCoords. In case of a label, coordinates are screen coordinates. Otherwise, coordinates are user coordinates.
`isLabel`	Boolean	Yes/no

Details

Source: base/coordselement.js, line 1605

addConstraint(terms)

Convert the point to CAS point and call update().

Parameters

Name Type Description

Name	Type	Description
`terms`	Array	[[zterm], xterm, yterm] defining terms for the z, x and y coordinate. The z-coordinate is optional and it is used for homogeneous coordinates. The coordinates may be either a JavaScript function, a string containing GEONExT syntax. This string will be converted into a JavaScript function here, a Number a pointer to a slider object. This will be converted into a call of the Value()-method of this slider.

terms

Array

[[zterm], xterm, yterm] defining terms for the z, x and y coordinate. The z-coordinate is optional and it is used for homogeneous coordinates. The coordinates may be either

a JavaScript function,
a string containing GEONExT syntax. This string will be converted into a JavaScript function here,
a Number
a pointer to a slider object. This will be converted into a call of the Value()-method of this slider.

Details

See

JXG.GeonextParser#geonext2JS

Source

base/coordselement.js, line 1487

addTransform(el, transform) → {JXG.CoordsElement}

Add transformations to this element.

Parameters

Name	Type	Description
`el`	JXG.GeometryElement
`transform`	JXG.Transformation \| Array	Either one JXG.Transformation or an array of JXG.Transformations.

Returns

Reference to itself.

Type: JXG.CoordsElement

Details

Overrides: JXG.GeometryElement#addTransform
Source: base/coordselement.js, line 1721

clearTransforms(el) → {JXG.CoordsElement}

Remove all JXG.Transformations of this element.

Parameters

Name	Type	Description
`el`	JXG.GeometryElement

Returns

Reference to itself.

Type: JXG.CoordsElement

Details

Overrides: JXG.GeometryElement#clearTransforms
Source: base/coordselement.js, line 1765

(private) findClosestSnapValue(pos) → {Number}

Find the closest entry in snapValues that is within snapValueDistance of pos.

Parameters

Name	Type	Description
`pos`	Number	Value for which snapping is calculated.

Returns

Index of the value to snap to, or null.

Type: Number

Details

Source: base/coordselement.js, line 567

free()

Converts a calculated element into a free element, i.e. it will delete all ancestors and transformations and, if the element is currently a glider, will remove the slideObject reference.

Details

Source: base/coordselement.js, line 1393

handleAttractors() → {JXG.CoordsElement}

A point can change its type from free point to glider and vice versa. If it is given an array of attractor elements (attribute attractors) and the attribute attractorDistance then the point will be made a glider if it less than attractorDistance apart from one of its attractor elements. If attractorDistance is equal to zero, the point stays in its current form.

Returns

Reference to this element

Type: JXG.CoordsElement

Details

Source: base/coordselement.js, line 1077

handleSnapToPoints(force) → {JXG.CoordsElement}

Let a point snap to the nearest point in distance of JXG.Point#attractorDistance. The function uses the coords object of the point as its actual position.

Parameters

Name	Type	Description
`force`	Boolean	force snapping independent of what the snaptogrid attribute says

Returns

Reference to this element

Type: JXG.CoordsElement

Details

Source: base/coordselement.js, line 993

makeGlider(slide)

Convert the point to glider and update the construction. To move the point visual onto the glider, a call of board update is necessary.

Parameters

Name	Type	Description
`slide`	String \| Object	The object the point will be bound to.

Details

Source: base/coordselement.js, line 1302

moveAlong(path, time, optionsopt) → {JXG.CoordsElement}

Starts an animation which moves the point along a given path in given time.

Parameters

Name Type Attributes Description

path

Array | function

The path the point is moved on. This can be either an array of arrays or containing x and y values of the points of the path, or an array of points, or a function taking the amount of elapsed time since the animation has started and returns an array containing a x and a y value or NaN. In case of NaN the animation stops.

time

Number

The time in milliseconds in which to finish the animation

options

Object

Optional settings for the animation.

Properties

Name	Type	Attributes	Default	Description
`callback`	function	<optional>		A function that is called as soon as the animation is finished.
`interpolate`	Boolean	<optional>	`true`	If `path` is an array moveAlong() will interpolate the path using JXG.Math.Numerics.Neville. Set this flag to false if you don't want to use interpolation.

Returns

Reference to itself.

Type: JXG.CoordsElement

Details

See

Source

base/coordselement.js, line 1901

moveAlongES6(where, timeopt, optionsopt)

ES6 version of JXG.CoordsElement#moveAlong using a promise.

Example

var A = board.create('point', [4, 4]);
A.moveAlongES6([[3, -2], [4, 0], [3, 1], [4, 4]], 2000)
    .then(() => A.moveToES6([-3, -3], 1000));

Parameters

Name	Type	Attributes	Description
`where`	Array		Array containing the x and y coordinate of the target location.
`time`	Number	<optional>	Number of milliseconds the animation should last.
`options`	Object	<optional>	Optional settings for the animation

Returns

Promise

Details

See

JXG.CoordsElement#moveAlong

Source

base/coordselement.js, line 2263

moveTo(where, timeopt, optionsopt) → {JXG.CoordsElement}

Starts an animated point movement towards the given coordinates where. The animation is done after time milliseconds. If the second parameter is not given or is equal to 0, setPosition() is called, see JXG.CoordsElement#setPosition, i.e. the coordinates are changed without animation.

Example

// moveTo() with different easing options and callback options
let yInit = 3
let [A, B, C, D] = ['==', '<>', '<', '>'].map((s) => board.create('point', [4, yInit--], { name: s, label: { fontSize: 24 } }))
let seg = board.create('segment', [A, [() => A.X(), 0]])  // shows linear

let isLeftRight = true;
let buttonMove = board.create('button', [-2, 4, 'left',
() => {
   isLeftRight = !isLeftRight;
   buttonMove.rendNodeButton.innerHTML = isLeftRight ? 'left' : 'right';
   let x = isLeftRight ? 4 : -4;
   let sym = isLeftRight ? 'triangleleft' : 'triangleright';

   A.moveTo([x, 3], 1000, { callback: () => A.setAttribute({ face: sym, size: 5 }) });
   B.moveTo([x, 2], 1000, { callback: () => B.setAttribute({ face: sym, size: 5 }), effect: "<>" });
   C.moveTo([x, 1], 1000, { callback: () => C.setAttribute({ face: sym, size: 5 }), effect: "<" });
   D.moveTo([x, 0], 1000, { callback: () => D.setAttribute({ face: sym, size: 5 }), effect: ">" });

}]);

Parameters

Name Type Attributes Description

where

Array

Array containing the x and y coordinate of the target location.

time

Number

Number of milliseconds the animation should last.

options

Object

Optional settings for the animation

Properties

Name	Type	Attributes	Default	Description
`callback`	function	<optional>		A function that is called as soon as the animation is finished.
`effect`	String	<optional>	`'<>'\|'>'\|'<'\|'--'\|'=='`	animation effects like speed fade in and out. possible values are '<>' for speed increase on start and slow down at the end (default), '<' for speed up, '>' for slow down, and '--' (or '==') for constant speed during the whole animation.

Returns

Reference to itself.

Type: JXG.CoordsElement

Details

See

Source

base/coordselement.js, line 2047

moveToES6(where, timeopt, optionsopt)

ES6 version of JXG.CoordsElement#moveTo using a promise.

Examples

var A = board.create('point', [4, 4]);
A.moveToES6([-3, 3], 1000)
    .then(() => A.moveToES6([-3, -3], 1000))
    .then(() => A.moveToES6([3, -3], 1000))
    .then(() => A.moveToES6([3, -3], 1000));

var A = board.create('point', [4, 4]);
        A.moveToES6([-3, 3], 1000)
            .then(function() {
                return A.moveToES6([-3, -3], 1000);
            }).then(function() {
                return A.moveToES6([ 3, -3], 1000);
            }).then(function() {
                return A.moveToES6([ 3, -3], 1000);
            }).then(function() {
                return A.moveAlongES6([[3, -2], [4, 0], [3, 1], [4, 4]], 5000);
            }).then(function() {
                return A.visitES6([-4, -4], 3000);
            });

Parameters

Name	Type	Attributes	Description
`where`	Array		Array containing the x and y coordinate of the target location.
`time`	Number	<optional>	Number of milliseconds the animation should last.
`options`	Object	<optional>	Optional settings for the animation

Returns

Promise

Details

See

JXG.CoordsElement#moveTo

Source

base/coordselement.js, line 2346

popSlideObject()

Remove the last slideObject. If there are more than one elements the point is bound to, the second last element is the new active slideObject.

Details

Source: base/coordselement.js, line 1358

removeTransform(transform) → {JXG.CoordsElement}

Remove transformations of this element.

Parameters

Name	Type	Description
`transform`	JXG.Transformation \| Array	Either one JXG.Transformation or an array of JXG.Transformations.

Returns

Reference to itself.

Type: JXG.CoordsElement

Details

Overrides: JXG.GeometryElement#removeTransform
Source: base/coordselement.js, line 1744

setGliderPosition(x) → {JXG.Point}

Sets the position of a glider relative to the defining elements of the JXG.CoordsElement#slideObject.

Parameters

Name	Type	Description
`x`	Number

Returns

Reference to the point element.

Type: JXG.Point

Details

Source: base/coordselement.js, line 1288

setPosition(method, coords) → {JXG.CoordsElement}

Sets coordinates and calls the element's update() method.

Parameters

Name	Type	Description
`method`	Number	The type of coordinates used here. Possible values are JXG.COORDS_BY_USER and JXG.COORDS_BY_SCREEN.
`coords`	Array	coordinates in screen/user units

Returns

Type: JXG.CoordsElement

Details

Overrides: JXG.GeometryElement#setPosition
Source: base/coordselement.js, line 1278

setPositionByTransform(method, tv) → {JXG.CoordsElement}

Translates the point by tv = (x, y).

Parameters

Name	Type	Description
`method`	Number	The type of coordinates used here. Possible values are JXG.COORDS_BY_USER and JXG.COORDS_BY_SCREEN.
`tv`	Array	(x, y)

Returns

Type: JXG.CoordsElement

Details

Source: base/coordselement.js, line 1249

setPositionDirectly(method, coords) → {JXG.CoordsElement}

Sets coordinates and calls the elements's update() method.

Parameters

Name	Type	Description
`method`	Number	The type of coordinates used here. Possible values are JXG.COORDS_BY_USER and JXG.COORDS_BY_SCREEN.
`coords`	Array	coordinates `([z], x, y)` in screen/user units

Returns

this element

Type: JXG.CoordsElement

Details

Overrides: JXG.GeometryElement#setPositionDirectly
Source: base/coordselement.js, line 1175

snapToGrid(force) → {JXG.CoordsElement}

Alias for JXG.Element#handleSnapToGrid

Parameters

Name	Type	Description
`force`	Boolean	force snapping independent of what the snaptogrid attribute says

Returns

Reference to this element

Type: JXG.CoordsElement

Details

Overrides: JXG.GeometryElement#snapToGrid
Source: base/coordselement.js, line 981

snapToPoints(force) → {JXG.CoordsElement}

Alias for JXG.CoordsElement#handleSnapToPoints.

Parameters

Name	Type	Description
`force`	Boolean	force snapping independent of what the snaptogrid attribute says

Returns

Reference to this element

Type: JXG.CoordsElement

Details

Overrides: JXG.GeometryElement#snapToPoints
Source: base/coordselement.js, line 1063

(private) updateConstraint()

Dummy function for unconstrained points or gliders.

Details

Source: base/coordselement.js, line 194

(private) updateCoords()

Updates the coordinates of the element.

Details

Source: base/coordselement.js, line 202

(private) updateGlider()

Update of glider in case of dragging the glider or setting the postion of the glider. The relative position of the glider has to be updated.

In case of a glider on a line: If the second point is an ideal point, then -1 < this.position < 1, this.position==+/-1 equals point2, this.position==0 equals point1

If the first point is an ideal point, then 0 < this.position < 2 this.position==0 or 2 equals point1, this.position==1 equals point2

Details

Source: base/coordselement.js, line 252

(private) updateGliderFromParent()

Update of a glider in case a parent element has been updated. That means the relative position of the glider stays the same.

Details

Source: base/coordselement.js, line 596

updateTransform(fromParent) → {JXG.CoordsElement}

Applies the transformations of the element. This method applies to text and images. Point transformations are handled differently.

Parameters

Name	Type	Description
`fromParent`	Boolean	True if the drag comes from a child element. Unused.

Returns

Reference to itself.

Type: JXG.CoordsElement

Details

Source: base/coordselement.js, line 1680

visit(where, time, optionsopt) → {JXG.CoordsElement}

Starts an animated point movement towards the given coordinates where. After arriving at where the point moves back to where it started. The animation is done after time milliseconds.

Example

// visit() with different easing options
let yInit = 3
let [A, B, C, D] = ['==', '<>', '<', '>'].map((s) => board.create('point', [4, yInit--], { name: s, label: { fontSize: 24 } }))
let seg = board.create('segment', [A, [() => A.X(), 0]])  // shows linear

let isLeftRight = true;
let buttonVisit = board.create('button', [0, 4, 'visit',
   () => {
       let x = isLeftRight ? 4 : -4

       A.visit([-x, 3], 4000, { effect: "==", repeat: 2 })  // linear
       B.visit([-x, 2], 4000, { effect: "<>", repeat: 2 })
       C.visit([-x, 1], 4000, { effect: "<", repeat: 2 })
       D.visit([-x, 0], 4000, { effect: ">", repeat: 2 })
   }])

Parameters

Name Type Attributes Description

where

Array

Array containing the x and y coordinate of the target location.

time

Number

Number of milliseconds the animation should last.

options

Object

Optional settings for the animation

Properties

Name	Type	Attributes	Default	Description
`callback`	function	<optional>		A function that is called as soon as the animation is finished.
`effect`	String	<optional>	`'<>'\|'>'\|'<'\|'=='\|'--'`	animation effects like speed fade in and out. possible values are '<>' for speed increase on start and slow down at the end (default), '<' for speed up, '>' for slow down, and '--' (or '==') for constant speed during the whole animation.
`repeat`	Number	<optional>	`1`	How often this animation should be repeated.

Returns

Reference to itself.

Type: JXG.CoordsElement

Details

See

Source

base/coordselement.js, line 2172

visitES6(where, timeopt, optionsopt)

ES6 version of JXG.CoordsElement#moveVisit using a promise.

Example

var A = board.create('point', [4, 4]);
A.visitES6([-4, -4], 3000)
    .then(() => A.moveToES6([-3, 3], 1000));

Parameters

Name	Type	Attributes	Description
`where`	Array		Array containing the x and y coordinate of the target location.
`time`	Number	<optional>	Number of milliseconds the animation should last.
`options`	Object	<optional>	Optional settings for the animation

Returns

Promise

Details

See

JXG.CoordsElement#visit

Source

base/coordselement.js, line 2386

(static) create(Callback, board, coords, attr, arg1, arg2) → {Object}

Generic method to create point, text or image. Determines the type of the construction, i.e. free, or constrained by function, transformation or of glider type.

Parameters

Name	Type	Description
`Callback`	Object	Object type, e.g. Point, Text or Image
`board`	Object	Link to the board object
`coords`	Array	Array with coordinates. This may be: array of numbers, function returning an array of numbers, array of functions returning a number, object and transformation. If the attribute "slideObject" exists, a glider element is constructed.
`attr`	Object	Attributes object
`arg1`	Object	Optional argument 1: in case of text this is the text content, in case of an image this is the url.
`arg2`	Array	Optional argument 2: in case of image this is an array containing the size of the image.