fabric.js/src/shapes/text.class.js

(function(global) {

  "use strict";

  var fabric = global.fabric || (global.fabric = { }),
      extend = fabric.util.object.extend,
      clone = fabric.util.object.clone,
      toFixed = fabric.util.toFixed,
      supportsLineDash = fabric.StaticCanvas.supports('setLineDash');

  if (fabric.Text) {
    fabric.warn('fabric.Text is already defined');
    return;
  }

  var stateProperties = fabric.Object.prototype.stateProperties.concat();
  stateProperties.push(
    'fontFamily',
    'fontWeight',
    'fontSize',
    'text',
    'textDecoration',
    'textAlign',
    'fontStyle',
    'lineHeight',
    'textBackgroundColor',
    'useNative',
    'path'
  );

  /**
   * Text class
   * @class fabric.Text
   * @extends fabric.Object
   * @return {fabric.Text} thisArg
   * @tutorial {@link http://fabricjs.com/fabric-intro-part-2/#text}
   * @see {@link fabric.Text#initialize} for constructor definition
   */
  fabric.Text = fabric.util.createClass(fabric.Object, /** @lends fabric.Text.prototype */ {

    /**
     * Properties which when set cause object to change dimensions
     * @type Object
     * @private
     */
    _dimensionAffectingProps: {
      fontSize: true,
      fontWeight: true,
      fontFamily: true,
      textDecoration: true,
      fontStyle: true,
      lineHeight: true,
      stroke: true,
      strokeWidth: true,
      text: true
    },

    /**
     * Retrieves object's fontSize
     * @method getFontSize
     * @memberOf fabric.Text.prototype
     * @return {String} Font size (in pixels)
     */

    /**
     * Sets object's fontSize
     * @method setFontSize
     * @memberOf fabric.Text.prototype
     * @param {Number} fontSize Font size (in pixels)
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Retrieves object's fontWeight
     * @method getFontWeight
     * @memberOf fabric.Text.prototype
     * @return {(String|Number)} Font weight
     */

    /**
     * Sets object's fontWeight
     * @method setFontWeight
     * @memberOf fabric.Text.prototype
     * @param {(Number|String)} fontWeight Font weight
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Retrieves object's fontFamily
     * @method getFontFamily
     * @memberOf fabric.Text.prototype
     * @return {String} Font family
     */

    /**
     * Sets object's fontFamily
     * @method setFontFamily
     * @memberOf fabric.Text.prototype
     * @param {String} fontFamily Font family
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Retrieves object's text
     * @method getText
     * @memberOf fabric.Text.prototype
     * @return {String} text
     */

    /**
     * Sets object's text
     * @method setText
     * @memberOf fabric.Text.prototype
     * @param {String} text Text
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Retrieves object's textDecoration
     * @method getTextDecoration
     * @memberOf fabric.Text.prototype
     * @return {String} Text decoration
     */

    /**
     * Sets object's textDecoration
     * @method setTextDecoration
     * @memberOf fabric.Text.prototype
     * @param {String} textDecoration Text decoration
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Retrieves object's fontStyle
     * @method getFontStyle
     * @memberOf fabric.Text.prototype
     * @return {String} Font style
     */

    /**
     * Sets object's fontStyle
     * @method setFontStyle
     * @memberOf fabric.Text.prototype
     * @param {String} fontStyle Font style
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Retrieves object's lineHeight
     * @method getLineHeight
     * @memberOf fabric.Text.prototype
     * @return {Number} Line height
     */

    /**
     * Sets object's lineHeight
     * @method setLineHeight
     * @memberOf fabric.Text.prototype
     * @param {Number} lineHeight Line height
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Retrieves object's textAlign
     * @method getTextAlign
     * @memberOf fabric.Text.prototype
     * @return {String} Text alignment
     */

    /**
     * Sets object's textAlign
     * @method setTextAlign
     * @memberOf fabric.Text.prototype
     * @param {String} textAlign Text alignment
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Retrieves object's textBackgroundColor
     * @method getTextBackgroundColor
     * @memberOf fabric.Text.prototype
     * @return {String} Text background color
     */

    /**
     * Sets object's textBackgroundColor
     * @method setTextBackgroundColor
     * @memberOf fabric.Text.prototype
     * @param {String} textBackgroundColor Text background color
     * @return {fabric.Text}
     * @chainable
     */

    /**
     * Type of an object
     * @type String
     * @default
     */
    type:                 'text',

    /**
     * Font size (in pixels)
     * @type Number
     * @default
     */
    fontSize:             40,

    /**
     * Font weight (e.g. bold, normal, 400, 600, 800)
     * @type {(Number|String)}
     * @default
     */
    fontWeight:           'normal',

    /**
     * Font family
     * @type String
     * @default
     */
    fontFamily:           'Times New Roman',

    /**
     * Text decoration Possible values: "", "underline", "overline" or "line-through".
     * @type String
     * @default
     */
    textDecoration:       '',

    /**
     * Text alignment. Possible values: "left", "center", or "right".
     * @type String
     * @default
     */
    textAlign:            'left',

    /**
     * Font style . Possible values: "", "normal", "italic" or "oblique".
     * @type String
     * @default
     */
    fontStyle:            '',

    /**
     * Line height
     * @type Number
     * @default
     */
    lineHeight:           1.3,

    /**
     * Background color of text lines
     * @type String
     * @default
     */
    textBackgroundColor:  '',

    /**
     * URL of a font file, when using Cufon
     * @type String | null
     * @default
     */
    path:                 null,

    /**
     * Indicates whether canvas native text methods should be used to render text (otherwise, Cufon is used)
     * @type Boolean
     * @default
     */
    useNative:            true,

    /**
     * List of properties to consider when checking if state of an object is changed ({@link fabric.Object#hasStateChanged})
     * as well as for history (undo/redo) purposes
     * @type Array
     */
    stateProperties:      stateProperties,

    /**
     * When defined, an object is rendered via stroke and this property specifies its color.
     * <b>Backwards incompatibility note:</b> This property was named "strokeStyle" until v1.1.6
     * @type String
     * @default
     */
    stroke:               null,

    /**
     * Shadow object representing shadow of this shape.
     * <b>Backwards incompatibility note:</b> This property was named "textShadow" (String) until v1.2.11
     * @type fabric.Shadow
     * @default
     */
    shadow:               null,

    /**
     * Constructor
     * @param {String} text Text string
     * @param {Object} [options] Options object
     * @return {fabric.Text} thisArg
     */
    initialize: function(text, options) {
      options = options || { };

      this.text = text;
      this.__skipDimension = true;
      this.setOptions(options);
      this.__skipDimension = false;
      this._initDimensions();
      this.setCoords();
    },

    /**
     * Renders text object on offscreen canvas, so that it would get dimensions
     * @private
     */
    _initDimensions: function() {
      if (this.__skipDimension) return;
      var canvasEl = fabric.util.createCanvasElement();
      this._render(canvasEl.getContext('2d'));
    },

    /**
     * Returns string representation of an instance
     * @return {String} String representation of text object
     */
    toString: function() {
      return '#<fabric.Text (' + this.complexity() +
        '): { "text": "' + this.text + '", "fontFamily": "' + this.fontFamily + '" }>';
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     */
    _render: function(ctx) {

      var isInPathGroup = this.group && this.group.type !== 'group';
      if (isInPathGroup && !this.transformMatrix) {
        ctx.translate(-this.group.width/2 + this.left, -this.group.height / 2 + this.top);
      }
      else if (isInPathGroup && this.transformMatrix) {
        ctx.translate(-this.group.width/2, -this.group.height/2);
      }

      if (typeof Cufon === 'undefined' || this.useNative === true) {
        this._renderViaNative(ctx);
      }
      else {
        this._renderViaCufon(ctx);
      }
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     */
    _renderViaNative: function(ctx) {

      this.transform(ctx, fabric.isLikelyNode);

      this._setTextStyles(ctx);

      var textLines = this.text.split(/\r?\n/);

      this.width = this._getTextWidth(ctx, textLines);
      this.height = this._getTextHeight(ctx, textLines);

      this.clipTo && fabric.util.clipContext(this, ctx);

      this._renderTextBackground(ctx, textLines);

      if (this.textAlign !== 'left' && this.textAlign !== 'justify') {
        ctx.save();
        ctx.translate(this.textAlign === 'center' ? (this.width / 2) : this.width, 0);
      }

      ctx.save();
      this._setShadow(ctx);
      this._renderTextFill(ctx, textLines);
      this._renderTextStroke(ctx, textLines);
      this._removeShadow(ctx);
      ctx.restore();

      if (this.textAlign !== 'left' && this.textAlign !== 'justify') {
        ctx.restore();
      }

      this._renderTextDecoration(ctx, textLines);
      this.clipTo && ctx.restore();

      this._setBoundaries(ctx, textLines);
      this._totalLineHeight = 0;
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Array} textLines Array of all text lines
     */
    _setBoundaries: function(ctx, textLines) {
      this._boundaries = [ ];

      for (var i = 0, len = textLines.length; i < len; i++) {

        var lineWidth = this._getLineWidth(ctx, textLines[i]);
        var lineLeftOffset = this._getLineLeftOffset(lineWidth);

        this._boundaries.push({
          height: this.fontSize * this.lineHeight,
          width: lineWidth,
          left: lineLeftOffset
        });
      }
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     */
    _setTextStyles: function(ctx) {
      this._setFillStyles(ctx);
      this._setStrokeStyles(ctx);
      ctx.textBaseline = 'alphabetic';
      if (!this.skipTextAlign) {
        ctx.textAlign = this.textAlign;
      }
      ctx.font = this._getFontDeclaration();
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Array} textLines Array of all text lines
     * @return {Number} Height of fabric.Text object
     */
    _getTextHeight: function(ctx, textLines) {
      return this.fontSize * textLines.length * this.lineHeight;
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Array} textLines Array of all text lines
     * @return {Number} Maximum width of fabric.Text object
     */
    _getTextWidth: function(ctx, textLines) {
      var maxWidth = ctx.measureText(textLines[0] || '|').width;

      for (var i = 1, len = textLines.length; i < len; i++) {
        var currentLineWidth = ctx.measureText(textLines[i]).width;
        if (currentLineWidth > maxWidth) {
          maxWidth = currentLineWidth;
        }
      }
      return maxWidth;
    },

    /**
     * @private
     * @param {String} method Method name ("fillText" or "strokeText")
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {String} line Chars to render
     * @param {Number} left Left position of text
     * @param {Number} top Top position of text
     */
    _drawChars: function(method, ctx, chars, left, top) {
      ctx[method](chars, left, top);
    },

    /**
     * @private
     * @param {String} method Method name ("fillText" or "strokeText")
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {String} line Text to render
     * @param {Number} left Left position of text
     * @param {Number} top Top position of text
     * @param {Number} lineIndex Index of a line in a text
     */
    _drawTextLine: function(method, ctx, line, left, top, lineIndex) {
      // lift the line by quarter of fontSize
      top -= this.fontSize / 4;

      // short-circuit
      if (this.textAlign !== 'justify') {
        this._drawChars(method, ctx, line, left, top, lineIndex);
        return;
      }

      var lineWidth = ctx.measureText(line).width;
      var totalWidth = this.width;

      if (totalWidth > lineWidth) {
        // stretch the line
        var words = line.split(/\s+/);
        var wordsWidth = ctx.measureText(line.replace(/\s+/g, '')).width;
        var widthDiff = totalWidth - wordsWidth;
        var numSpaces = words.length - 1;
        var spaceWidth = widthDiff / numSpaces;

        var leftOffset = 0;
        for (var i = 0, len = words.length; i < len; i++) {
          this._drawChars(method, ctx, words[i], left + leftOffset, top, lineIndex);
          leftOffset += ctx.measureText(words[i]).width + spaceWidth;
        }
      }
      else {
        this._drawChars(method, ctx, line, left, top, lineIndex);
      }
    },

    /**
     * @private
     * @return {Number} Left offset
     */
    _getLeftOffset: function() {
      if (fabric.isLikelyNode) {
        return 0;
      }
      return -this.width / 2;
    },

    /**
     * @private
     * @return {Number} Top offset
     */
    _getTopOffset: function() {
      return -this.height / 2;
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Array} textLines Array of all text lines
     */
    _renderTextFill: function(ctx, textLines) {
      if (!this.fill && !this.skipFillStrokeCheck) return;

      this._boundaries = [ ];
      var lineHeights = 0;

      for (var i = 0, len = textLines.length; i < len; i++) {
        var heightOfLine = this._getHeightOfLine(ctx, i, textLines);
        lineHeights += heightOfLine;

        this._drawTextLine(
          'fillText',
          ctx,
          textLines[i],
          this._getLeftOffset(),
          this._getTopOffset() + lineHeights,
          i
        );
      }
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Array} textLines Array of all text lines
     */
    _renderTextStroke: function(ctx, textLines) {
      if (!this.stroke && !this.skipFillStrokeCheck) return;

      var lineHeights = 0;

      ctx.save();
      if (this.strokeDashArray) {
        // Spec requires the concatenation of two copies the dash list when the number of elements is odd
        if (1 & this.strokeDashArray.length) {
          this.strokeDashArray.push.apply(this.strokeDashArray, this.strokeDashArray);
        }
        supportsLineDash && ctx.setLineDash(this.strokeDashArray);
      }

      ctx.beginPath();
      for (var i = 0, len = textLines.length; i < len; i++) {
        var heightOfLine = this._getHeightOfLine(ctx, i, textLines);
        lineHeights += heightOfLine;

        this._drawTextLine(
          'strokeText',
          ctx,
          textLines[i],
          this._getLeftOffset(),
          this._getTopOffset() + lineHeights,
          i
        );
      }
      ctx.closePath();
      ctx.restore();
    },

    _getHeightOfLine: function() {
      return this.fontSize * this.lineHeight;
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Array} textLines Array of all text lines
     */
    _renderTextBackground: function(ctx, textLines) {
      this._renderTextBoxBackground(ctx);
      this._renderTextLinesBackground(ctx, textLines);
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     */
    _renderTextBoxBackground: function(ctx) {
      if (!this.backgroundColor) return;

      ctx.save();
      ctx.fillStyle = this.backgroundColor;

      ctx.fillRect(
        this._getLeftOffset(),
        this._getTopOffset(),
        this.width,
        this.height
      );

      ctx.restore();
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Array} textLines Array of all text lines
     */
    _renderTextLinesBackground: function(ctx, textLines) {
      if (!this.textBackgroundColor) return;

      ctx.save();
      ctx.fillStyle = this.textBackgroundColor;

      for (var i = 0, len = textLines.length; i < len; i++) {

        if (textLines[i] !== '') {

          var lineWidth = this._getLineWidth(ctx, textLines[i]);
          var lineLeftOffset = this._getLineLeftOffset(lineWidth);

          ctx.fillRect(
            this._getLeftOffset() + lineLeftOffset,
            this._getTopOffset() + (i * this.fontSize * this.lineHeight),
            lineWidth,
            this.fontSize * this.lineHeight
          );
        }
      }
      ctx.restore();
    },

    /**
     * @private
     * @param {Number} lineWidth Width of text line
     * @return {Number} Line left offset
     */
    _getLineLeftOffset: function(lineWidth) {
      if (this.textAlign === 'center') {
        return (this.width - lineWidth) / 2;
      }
      if (this.textAlign === 'right') {
        return this.width - lineWidth;
      }
      return 0;
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {String} line Text line
     * @return {Number} Line width
     */
    _getLineWidth: function(ctx, line) {
      return this.textAlign === 'justify'
        ? this.width
        : ctx.measureText(line).width;
    },

    /**
     * @private
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Array} textLines Array of all text lines
     */
    _renderTextDecoration: function(ctx, textLines) {
      if (!this.textDecoration) return;

      // var halfOfVerticalBox = this.originY === 'top' ? 0 : this._getTextHeight(ctx, textLines) / 2;
      var halfOfVerticalBox = this._getTextHeight(ctx, textLines) / 2;
      var _this = this;

      /** @ignore */
      function renderLinesAtOffset(offset) {
        for (var i = 0, len = textLines.length; i < len; i++) {

          var lineWidth = _this._getLineWidth(ctx, textLines[i]);
          var lineLeftOffset = _this._getLineLeftOffset(lineWidth);

          ctx.fillRect(
            _this._getLeftOffset() + lineLeftOffset,
            ~~((offset + (i * _this._getHeightOfLine(ctx, i, textLines))) - halfOfVerticalBox),
            lineWidth,
            1);
        }
      }

      if (this.textDecoration.indexOf('underline') > -1) {
        renderLinesAtOffset(this.fontSize * this.lineHeight);
      }
      if (this.textDecoration.indexOf('line-through') > -1) {
        renderLinesAtOffset(this.fontSize * this.lineHeight - this.fontSize / 2);
      }
      if (this.textDecoration.indexOf('overline') > -1) {
        renderLinesAtOffset(this.fontSize * this.lineHeight - this.fontSize);
      }
    },

    /**
     * @private
     */
    _getFontDeclaration: function() {
      return [
        // node-canvas needs "weight style", while browsers need "style weight"
        (fabric.isLikelyNode ? this.fontWeight : this.fontStyle),
        (fabric.isLikelyNode ? this.fontStyle : this.fontWeight),
        this.fontSize + 'px',
        (fabric.isLikelyNode ? ('"' + this.fontFamily + '"') : this.fontFamily)
      ].join(' ');
    },

    /**
     * Renders text instance on a specified context
     * @param {CanvasRenderingContext2D} ctx Context to render on
     * @param {Boolean} [noTransform] When true, context is not transformed
     */
    render: function(ctx, noTransform) {
      // do not render if object is not visible
      if (!this.visible) return;

      ctx.save();
      this._render(ctx);
      if (!noTransform && this.active) {
        this.drawBorders(ctx);
        this.drawControls(ctx);
      }
      ctx.restore();
    },

    /**
     * Returns object representation of an instance
     * @param {Array} [propertiesToInclude] Any properties that you might want to additionally include in the output
     * @return {Object} Object representation of an instance
     */
    toObject: function(propertiesToInclude) {
      var object = extend(this.callSuper('toObject', propertiesToInclude), {
        text:                 this.text,
        fontSize:             this.fontSize,
        fontWeight:           this.fontWeight,
        fontFamily:           this.fontFamily,
        fontStyle:            this.fontStyle,
        lineHeight:           this.lineHeight,
        textDecoration:       this.textDecoration,
        textAlign:            this.textAlign,
        path:                 this.path,
        textBackgroundColor:  this.textBackgroundColor,
        useNative:            this.useNative
      });
      if (!this.includeDefaultValues) {
        this._removeDefaultValues(object);
      }
      return object;
    },

    /* _TO_SVG_START_ */
    /**
     * Returns SVG representation of an instance
     * @param {Function} [reviver] Method for further parsing of svg representation.
     * @return {String} svg representation of an instance
     */
    toSVG: function(reviver) {
      var markup = [ ],
          textLines = this.text.split(/\r?\n/),
          lineTopOffset = this.useNative
            ? this.fontSize * this.lineHeight
            : (-this._fontAscent - ((this._fontAscent / 5) * this.lineHeight)),

          textLeftOffset = -(this.width/2),
          textTopOffset = this.useNative
            ? this.fontSize - 1
            : (this.height/2) - (textLines.length * this.fontSize) - this._totalLineHeight,

          textAndBg = this._getSVGTextAndBg(lineTopOffset, textLeftOffset, textLines),
          shadowSpans = this._getSVGShadows(lineTopOffset, textLines);

      // move top offset by an ascent
      textTopOffset += (this._fontAscent ? ((this._fontAscent / 5) * this.lineHeight) : 0);

      markup.push(
        '<g transform="', this.getSvgTransform(), '">',
          textAndBg.textBgRects.join(''),
          '<text ',
            (this.fontFamily ? 'font-family="' + this.fontFamily.replace(/"/g,'\'') + '" ': ''),
            (this.fontSize ? 'font-size="' + this.fontSize + '" ': ''),
            (this.fontStyle ? 'font-style="' + this.fontStyle + '" ': ''),
            (this.fontWeight ? 'font-weight="' + this.fontWeight + '" ': ''),
            (this.textDecoration ? 'text-decoration="' + this.textDecoration + '" ': ''),
            'style="', this.getSvgStyles(), '" ',
            /* svg starts from left/bottom corner so we normalize height */
            'transform="translate(', toFixed(textLeftOffset, 2), ' ', toFixed(textTopOffset, 2), ')">',
            shadowSpans.join(''),
            textAndBg.textSpans.join(''),
          '</text>',
        '</g>'
      );

      return reviver ? reviver(markup.join('')) : markup.join('');
    },

    /**
     * @private
     * @param {Number} lineTopOffset Line top offset
     * @param {Array} textLines Array of all text lines
     * @return {Array}
     */
    _getSVGShadows: function(lineTopOffset, textLines) {
      var shadowSpans = [],
          i, len,
          lineTopOffsetMultiplier = 1;

      if (!this.shadow || !this._boundaries) {
        return shadowSpans;
      }

      for (i = 0, len = textLines.length; i < len; i++) {
        if (textLines[i] !== '') {
          var lineLeftOffset = (this._boundaries && this._boundaries[i]) ? this._boundaries[i].left : 0;
          shadowSpans.push(
            '<tspan x="',
            toFixed((lineLeftOffset + lineTopOffsetMultiplier) + this.shadow.offsetX, 2),
            ((i === 0 || this.useNative) ? '" y' : '" dy'), '="',
            toFixed(this.useNative
              ? ((lineTopOffset * i) - this.height / 2 + this.shadow.offsetY)
              : (lineTopOffset + (i === 0 ? this.shadow.offsetY : 0)), 2),
            '" ',
            this._getFillAttributes(this.shadow.color), '>',
            fabric.util.string.escapeXml(textLines[i]),
          '</tspan>');
          lineTopOffsetMultiplier = 1;
        } else {
          // in some environments (e.g. IE 7 & 8) empty tspans are completely ignored, using a lineTopOffsetMultiplier
          // prevents empty tspans
          lineTopOffsetMultiplier++;
        }
      }

      return shadowSpans;
    },

    /**
     * @private
     * @param {Number} lineTopOffset Line top offset
     * @param {Number} textLeftOffset Text left offset
     * @param {Array} textLines Array of all text lines
     * @return {Object}
     */
    _getSVGTextAndBg: function(lineTopOffset, textLeftOffset, textLines) {
      var textSpans = [ ], textBgRects = [ ], i, lineLeftOffset, len, lineTopOffsetMultiplier = 1;

      // bounding-box background
      if (this.backgroundColor && this._boundaries) {
        textBgRects.push(
          '<rect ',
            this._getFillAttributes(this.backgroundColor),
            ' x="',
            toFixed(-this.width / 2, 2),
            '" y="',
            toFixed(-this.height / 2, 2),
            '" width="',
            toFixed(this.width, 2),
            '" height="',
            toFixed(this.height, 2),
          '"></rect>');
      }

      // text and text-background
      for (i = 0, len = textLines.length; i < len; i++) {
        if (textLines[i] !== '') {
          lineLeftOffset = (this._boundaries && this._boundaries[i]) ? toFixed(this._boundaries[i].left, 2) : 0;
          textSpans.push(
            '<tspan x="',
              lineLeftOffset, '" ',
              (i === 0 || this.useNative ? 'y' : 'dy'), '="',
              toFixed(this.useNative ? ((lineTopOffset * i) - this.height / 2) : (lineTopOffset * lineTopOffsetMultiplier), 2) , '" ',
              // doing this on <tspan> elements since setting opacity on containing <text> one doesn't work in Illustrator
              this._getFillAttributes(this.fill), '>',
              fabric.util.string.escapeXml(textLines[i]),
            '</tspan>'
          );
          lineTopOffsetMultiplier = 1;
        }
        else {
          // in some environments (e.g. IE 7 & 8) empty tspans are completely ignored, using a lineTopOffsetMultiplier
          // prevents empty tspans
          lineTopOffsetMultiplier++;
        }

        if (!this.textBackgroundColor || !this._boundaries) continue;

        textBgRects.push(
          '<rect ',
            this._getFillAttributes(this.textBackgroundColor),
            ' x="',
            toFixed(textLeftOffset + this._boundaries[i].left, 2),
            '" y="',
            /* an offset that seems to straighten things out */
            toFixed((lineTopOffset * i) - this.height / 2, 2),
            '" width="',
            toFixed(this._boundaries[i].width, 2),
            '" height="',
            toFixed(this._boundaries[i].height, 2),
          '"></rect>');
      }
      return {
        textSpans: textSpans,
        textBgRects: textBgRects
      };
    },

    /**
     * Adobe Illustrator (at least CS5) is unable to render rgba()-based fill values
     * we work around it by "moving" alpha channel into opacity attribute and setting fill's alpha to 1
     *
     * @private
     * @param {Any} value
     * @return {String}
     */
    _getFillAttributes: function(value) {
      var fillColor = (value && typeof value === 'string') ? new fabric.Color(value) : '';
      if (!fillColor || !fillColor.getSource() || fillColor.getAlpha() === 1) {
        return 'fill="' + value + '"';
      }
      return 'opacity="' + fillColor.getAlpha() + '" fill="' + fillColor.setAlpha(1).toRgb() + '"';
    },
    /* _TO_SVG_END_ */

    /**
     * Sets specified property to a specified value
     * @param {String} key
     * @param {Any} value
     * @return {fabric.Text} thisArg
     * @chainable
     */
    _set: function(key, value) {
      if (key === 'fontFamily' && this.path) {
        this.path = this.path.replace(/(.*?)([^\/]*)(\.font\.js)/, '$1' + value + '$3');
      }
      this.callSuper('_set', key, value);

      if (key in this._dimensionAffectingProps) {
        this._initDimensions();
        this.setCoords();
      }
    },

    /**
     * Returns complexity of an instance
     * @return {Number} complexity
     */
    complexity: function() {
      return 1;
    }
  });

  /* _FROM_SVG_START_ */
  /**
   * List of attribute names to account for when parsing SVG element (used by {@link fabric.Text.fromElement})
   * @static
   * @memberOf fabric.Text
   * @see: http://www.w3.org/TR/SVG/text.html#TextElement
   */
  fabric.Text.ATTRIBUTE_NAMES = fabric.SHARED_ATTRIBUTES.concat(
    'x y font-family font-style font-weight font-size text-decoration'.split(' '));

  /**
   * Returns fabric.Text instance from an SVG element (<b>not yet implemented</b>)
   * @static
   * @memberOf fabric.Text
   * @param {SVGElement} element Element to parse
   * @param {Object} [options] Options object
   * @return {fabric.Text} Instance of fabric.Text
   */
  fabric.Text.fromElement = function(element, options) {
    if (!element) {
      return null;
    }

    var parsedAttributes = fabric.parseAttributes(element, fabric.Text.ATTRIBUTE_NAMES);
    options = fabric.util.object.extend((options ? fabric.util.object.clone(options) : { }), parsedAttributes);

    var text = new fabric.Text(element.textContent, options);

    /*
      Adjust positioning:
        x/y attributes in SVG correspond to the bottom-left corner of text bounding box
        top/left properties in Fabric correspond to center point of text bounding box
    */

    text.set({
      left: text.getLeft() + text.getWidth() / 2,
      top: text.getTop() - text.getHeight() / 2
    });

    return text;
  };
  /* _FROM_SVG_END_ */

  /**
   * Returns fabric.Text instance from an object representation
   * @static
   * @memberOf fabric.Text
   * @param object {Object} object Object to create an instance from
   * @return {fabric.Text} Instance of fabric.Text
   */
  fabric.Text.fromObject = function(object) {
    return new fabric.Text(object.text, clone(object));
  };

  fabric.util.createAccessors(fabric.Text);

})(typeof exports !== 'undefined' ? exports : this);