Class JXG.Text

JXG.GeometryElement,JXG.CoordsElement
↳ JXG.Text

Creates a new text object. Do not use this constructor to create a text. Use JXG.Board#create with type Text instead.

Defined in: text.js.
Extends JXG.CoordsElement, JXG.GeometryElement.

Class Summary
Constructor Attributes	Constructor Name and Description
	JXG.Text(board, coordinates, attributes, content) Construct and handle texts.

Fields borrowed from class JXG.GeometryElement:: _org_type, _pos, ancestors, aria, baseElement, board, childElements, cssClass, dash, dashScale, descendants, draft, dragToTopOfLayer, dump, element3D, elementClass, elType, fillColor, fillOpacity, fixed, frozen, gradient, gradientAngle, gradientCX, gradientCY, gradientEndOffset, gradientFR, gradientFX, gradientFY, gradientR, gradientSecondColor, gradientSecondOpacity, gradientStartOffset, hasLabel, highlight, highlightCssClass, highlighted, highlightFillColor, highlightFillOpacity, highlightStrokeColor, highlightStrokeOpacity, highlightStrokeWidth, id, ignoreForLabelAutoposition, inherits, isDraggable, isLabel, isReal, lastDragTime, layer, lineCap, methodMap, mouseover, name, needsRegularUpdate, needsUpdate, nonnegativeOnly, notExistingParents, numTraces, parents, precision, priv, quadraticform, rendNode, rotatable, scalable, shadow, snapToGrid, stdform, strokeColor, strokeOpacity, strokeWidth, subs, symbolic, tabindex, trace, traceAttributes, traces, transformations, transitionDuration, transitionProperties, type, visible, visProp, visPropCalc, withLabel
Fields borrowed from class JXG.CoordsElement:: coords, groups, isConstrained, needsUpdateFromParent, onPolygon, position, slideObject, slideObjects

Field Summary
Field Attributes	Field Name and Description
<private>	size Width and height of the text element in pixel.

Fields borrowed from class JXG.GeometryElement:: _org_type, _pos, ancestors, aria, baseElement, board, childElements, cssClass, dash, dashScale, descendants, draft, dragToTopOfLayer, dump, element3D, elementClass, elType, fillColor, fillOpacity, fixed, frozen, gradient, gradientAngle, gradientCX, gradientCY, gradientEndOffset, gradientFR, gradientFX, gradientFY, gradientR, gradientSecondColor, gradientSecondOpacity, gradientStartOffset, hasLabel, highlight, highlightCssClass, highlighted, highlightFillColor, highlightFillOpacity, highlightStrokeColor, highlightStrokeOpacity, highlightStrokeWidth, id, ignoreForLabelAutoposition, inherits, isDraggable, isLabel, isReal, lastDragTime, layer, lineCap, methodMap, mouseover, name, needsRegularUpdate, needsUpdate, nonnegativeOnly, notExistingParents, numTraces, parents, precision, priv, quadraticform, rendNode, rotatable, scalable, shadow, snapToGrid, stdform, strokeColor, strokeOpacity, strokeWidth, subs, symbolic, tabindex, trace, traceAttributes, traces, transformations, transitionDuration, transitionProperties, type, visible, visProp, visPropCalc, withLabel
Fields borrowed from class JXG.CoordsElement:: coords, groups, isConstrained, needsUpdateFromParent, onPolygon, position, slideObject, slideObjects

Method Summary
Method Attributes	Method Name and Description
<private>	_createFctUpdateText(text) This sets the updateText function of this element depending on the type of text content passed.
<private>	_setText(text) Defines new content.
	bounds() Returns the bounding box of the text element in user coordinates as an array of length 4: [upper left x, upper left y, lower right x, lower right y].
	calculateScore(radius, angle) Calculates the score of a label position with a given radius and angle.
<private>	checkForSizeUpdate() Used to save updateSize() calls.
<private>	convertGeonext2CSS(s) Converts the GEONExT tags and to HTML span tags with proper CSS formatting.
<private>	convertGeonextAndSketchometry2CSS(s, escape) Alias for convertGeonext2CSS and convertSketchometry2CSS
<private>	convertSketchometry2CSS(s, escape) Converts the sketchometry tag to HTML span tags with proper CSS formatting.
	crudeSizeEstimate() A very crude estimation of the dimensions of the textbox in case nothing else is available.
<private>	escapeTicks(s) Replace ticks by URI escape sequences
<private>	expandShortMath(expr) Converts shortened math syntax into correct syntax: 3x instead of 3x or (a+b)(3+1) instead of (a+b)(3+1).
<private>	generateTerm(contentStr, expand, avoidGeonext2JS) Converts the GEONExT syntax of the terms into JavaScript.
	getAnchorX() Returns the value of the attribute "anchorX".
	getAnchorY() Returns the value of the attribute "anchorY".
<private>	getNumberOfConflicts(x, y, w, h, whiteList) Computes the number of overlaps of a box of w pixels width, h pixels height and center (x, y) An overlap occurs when either: For labels/points: Their bounding boxes intersect For other objects: The object contains the center point of the box
	getSize() Return the width of the text element.
<private>	hasPoint(x, y)
<private>	notifyParents(content) Finds dependencies in a given term and notifies the parents by adding the dependent object to the found objects child elements.
<private>	poorMansTeX(s) Simple math rendering using HTML / CSS only.
	replaceSub(te) Replace _{} by <sub>
	replaceSup(te) Replace ^{} by <sup>
	setAutoPosition() Automatically positions the label by finding the optimal position.
	setCoords(x, y) Move the text to new coordinates.
	setText(text) Defines new content.
	setTextJessieCode(text) Defines new content but converts < and > to HTML entities before updating the DOM.
<private>	unescapeTicks(s) Replace escape sequences for ticks by ticks
	update(fromParent) Evaluates the text.
<private>	updateRenderer() The update function of the renderer is called.
	updateSize() Recompute the width and the height of the text box.
<private>	updateText() Dynamically created function to update the content of a text.
	utf8_decode(string) Decode unicode entities into characters.
<private>	valueTagToJessieCode(contentStr) Replace value-tags in string by JessieCode functions.

Methods borrowed from class JXG.GeometryElement:: _set, addChild, addDescendants, addParents, addParentsFromJCFunctions, addRotation, addTicks, addTransform, animate, clearTrace, cloneToBackground, countChildren, createGradient, createLabel, draggable, eval, evalVisProp, formatNumberLocale, fullUpdate, generatePolynomial, getAttribute, getAttributes, getLabelAnchor, getName, getParents, getProperty, getSnapSizes, getTextAnchor, getType, handleSnapToGrid, hide, hideElement, noHighlight, normalize, prepareUpdate, remove, removeAllTicks, removeChild, removeDescendants, removeTicks, resolveShortcuts, setArrow, setAttribute, setDash, setDisplayRendNode, setLabel, setLabelText, setName, setParents, setPosition, setPositionDirectly, setProperty, show, showElement, snapToPoints, updateVisibility, useLocale
Methods borrowed from class JXG.CoordsElement:: _anim, addAnchor, addConstraint, Coords, Dist, findClosestSnapValue, free, handleAttractors, handleSnapToPoints, makeGlider, moveAlong, moveAlongES6, moveTo, moveToES6, popSlideObject, setGliderPosition, setPositionByTransform, updateConstraint, updateCoords, updateGlider, updateGliderFromParent, updateTransform, visit, visitES6, X, XEval, Y, YEval, Z, ZEval

Events borrowed from class JXG.GeometryElement:: attribute, attribute:key, down, drag, keydrag, mousedown, mousedrag, mousemove, mouseout, mouseover, mouseup, move, out, over, pendown, pendrag, penup, touchdown, touchdrag, touchup, up

Class Detail

JXG.Text(board, coordinates, attributes, content)

Construct and handle texts. The coordinates can be relative to the coordinates of an element given in JXG.Options#text.anchor. MathJax, HTML and GEONExT syntax can be handled.

Parameters:
{string|JXG.Board} board: The board the new text is drawn on.
{Array} coordinates: An array with the user coordinates of the text.
{Object} attributes: An object containing visual properties and optional a name and a id.
{string|function} content: A string or a function returning a string.

Field Detail

<private> {Array} size

Width and height of the text element in pixel.

Method Detail

<private> _createFctUpdateText(text)

This sets the updateText function of this element depending on the type of text content passed. Used by JXG.Text#_setText.

Parameters:
{String|Function|Number} text

See:: JXG.Text#_setText

<private> {JXG.Text} _setText(text)

Defines new content. This is used by JXG.Text#setTextJessieCode and JXG.Text#setText. This is required because JessieCode needs to filter all Texts inserted into the DOM and thus has to replace setText by setTextJessieCode.

Parameters:
{String|Function|Number} text

Returns:: {JXG.Text}

bounds()

Returns the bounding box of the text element in user coordinates as an array of length 4: [upper left x, upper left y, lower right x, lower right y]. The method assumes that the lower left corner is at position [el.X(), el.Y()] of the text element el, i.e. the attributes anchorX, anchorY are ignored.

Attention: for labels, [0, 0, 0, 0] is returned.

Returns:: Array

{number} calculateScore(radius, angle)

Calculates the score of a label position with a given radius and angle. The score is calculated by the following rules:

the maximum score is 0
if the label is outside of the bounding box, the score is reduced by 1
for each conflict, the score is reduced by 1
the score is reduced by the displacement (angle difference between old and new position) of the label
the score is reduced by the angle between the original label position and the new label position

Parameters:
{number} radius: radius in pixels
{number} angle: angle in radians

Returns:: {number} Position score, higher values indicate better positions

<private> checkForSizeUpdate()

Used to save updateSize() calls. Called in JXG.Text.update That means this.update() has been called. More tests are in JXG.Renderer.updateTextStyle. The latter tests are one update off. But this should pose not too many problems, since it affects fontSize and cssClass changes.

<private> convertGeonext2CSS(s)

Converts the GEONExT tags and to HTML span tags with proper CSS formatting.

Parameters:
s

See:: JXG.Text.poorMansTeX; JXG.Text._setText

<private> convertGeonextAndSketchometry2CSS(s, escape)

Alias for convertGeonext2CSS and convertSketchometry2CSS

Parameters:
{String|Function|Number} s: Text
{Boolean} escape: Flag if ticks should be escaped

See:: JXG.Text.convertGeonext2CSS; JXG.Text.convertSketchometry2CSS

<private> convertSketchometry2CSS(s, escape)

Converts the sketchometry tag to HTML span tags with proper CSS formatting.

Parameters:
{String|Function|Number} s: Text
{Boolean} escape: Flag if ticks should be escaped. Escaping is necessary if s is a text. It has to be avoided if s is a function returning text.

See:: JXG.Text._setText; JXG.Text.convertGeonextAndSketchometry2CSS

{Array} crudeSizeEstimate()

A very crude estimation of the dimensions of the textbox in case nothing else is available.

Returns:: {Array}

<private> escapeTicks(s)

Replace ticks by URI escape sequences

Parameters:
{String} s

Returns:: String

<private> {string} expandShortMath(expr)

Converts shortened math syntax into correct syntax: 3x instead of 3*x or (a+b)(3+1) instead of (a+b)*(3+1).

Parameters:
expr

Returns:: {string} expanded String

<private> generateTerm(contentStr, expand, avoidGeonext2JS)

Converts the GEONExT syntax of the terms into JavaScript. Also, all Objects whose name appears in the term are searched and the text is added as child to these objects. This method is called if the attribute parse==true is set. Obsolete, replaced by JXG.Text.valueTagToJessieCode

Parameters:
contentStr
expand
avoidGeonext2JS

See:: JXG.GeonextParser#geonext2JS; JXG.Text#valueTagToJessieCode

getAnchorX()

Returns the value of the attribute "anchorX". If this equals "auto", returns "left", "middle", or "right", depending on the value of the attribute "position".

Returns:: String

getAnchorY()

Returns the value of the attribute "anchorY". If this equals "auto", returns "bottom", "middle", or "top", depending on the value of the attribute "position".

Returns:: String

<private> {Number} getNumberOfConflicts(x, y, w, h, whiteList)

Computes the number of overlaps of a box of w pixels width, h pixels height and center (x, y) An overlap occurs when either:

For labels/points: Their bounding boxes intersect
For other objects: The object contains the center point of the box

Parameters:
{Number} x: x-coordinate of the center (screen coordinates)
{Number} y: y-coordinate of the center (screen coordinates)
{Number} w: width of the box in pixel
{Number} h: width of the box in pixel
{Array} whiteList Optional: array of ids which should be ignored

Returns:: {Number} Number of overlapping elements

{Array} getSize()

Return the width of the text element.

Returns:: {Array} [width, height] in pixel

<private> {Boolean} hasPoint(x, y)

Parameters:
{Number} x
{Number} y

Returns:: {Boolean}

<private> notifyParents(content)

Finds dependencies in a given term and notifies the parents by adding the dependent object to the found objects child elements.

Parameters:
{String} content: String containing dependencies for the given object.

<private> {String|Array} poorMansTeX(s)

Simple math rendering using HTML / CSS only. In case of array, handle each entry separately and return array with the rendering strings.

Parameters:
{String|Array} s

Returns:: {String|Array}

See:: JXG.Text#convertGeonextAndSketchometry2CSS; JXG.Text#replaceSub; JXG.Text#replaceSup; JXG.Text#convertGeonextAndSketchometry2CSS

{String} replaceSub(te)

Replace _{} by <sub>

Parameters:
{String} te: String containing _{}.

Returns:: {String} Given string with _{} replaced by <sub>.

{String} replaceSup(te)

Replace ^{} by <sup>

Parameters:
{String} te: String containing ^{}.

Returns:: {String} Given string with ^{} replaced by <sup>.

{JXG.Text} setAutoPosition()

Automatically positions the label by finding the optimal position. Aims to minimize conflicts while maintaining readability.

The method tests 60 different angles (0 to 2π) at 3 different distances (radii). It evaluates each position using calculateScore(radius, angle) and chooses the position with the highest score. Then the label's anchor points and offset are adjusted accordingly.

Returns:: {JXG.Text} Reference to the text object.

{object} setCoords(x, y)

Move the text to new coordinates.

Parameters:
{number} x
{number} y

Returns:: {object} reference to the text object.

{JXG.Text} setText(text)

Defines new content.

Parameters:
{String|function} text

Returns:: {JXG.Text} Reference to the text object.

setTextJessieCode(text)

Defines new content but converts < and > to HTML entities before updating the DOM.

Parameters:
{String|function} text

<private> unescapeTicks(s)

Replace escape sequences for ticks by ticks

Parameters:
{String} s

Returns:: String

update(fromParent)

Evaluates the text. Then, the update function of the renderer is called.

Parameters:
fromParent

<private> updateRenderer()

The update function of the renderer is called.

{this} updateSize()

Recompute the width and the height of the text box. Updates the array JXG.Text#size with pixel values. The result may differ from browser to browser by some pixels. In canvas an old IEs we use a very crude estimation of the dimensions of the textbox. JSXGraph needs JXG.Text#size for applying rotations in IE and for aligning text.

Returns:: {this} [description]

<private> updateText()

Dynamically created function to update the content of a text. Can not be overwritten.

<value> tags will not be evaluated if text is provided by a function

Sets the property plaintext of the text element.

{String} utf8_decode(string)

Decode unicode entities into characters.

Parameters:
{String} string

Returns:: {String}

<private> valueTagToJessieCode(contentStr)

Replace value-tags in string by JessieCode functions.

Parameters:
{String} contentStr

Returns:: String

Examples:

JSXGraph 1.12.0 Reference

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Class JXG.Text