using clamp js to clamp lines of text

HTML

<div class="clamp1 mb-3">Cras vel ligula a elit pretium convallis. Nunc ac nisl nisi. Vestibulum ut ullamcorper nibh. Phasellus dictum nisi quis ullamcorper finibus. Phasellus fringilla purus ut augue varius vulputate. Nullam nec nisl dignissim, varius sem pretium, commodo orci. Cras tortor nisl, pharetra sodales lobortis a, vestibulum ut libero. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Nulla facilisi. Pellentesque rutrum urna elit, sed cursus felis placerat efficitur. Curabitur tempor velit magna, mollis malesuada risus lacinia sed. Mauris tristique id mi et cursus. Quisque consectetur velit in lacus euismod scelerisque. Vestibulum ac malesuada libero, eget auctor turpis. Integer pellentesque a ipsum non faucibus. Quisque ultricies sapien ut tellus bibendum aliquam.</div>

<div class='clamp2 mb-3'>Cras vel ligula a elit pretium convallis. Nunc ac nisl nisi. Vestibulum ut ullamcorper nibh. Phasellus dictum nisi quis ullamcorper finibus. Phasellus fringilla purus ut augue varius vulputate. Nullam nec nisl dignissim, varius sem pretium, commodo orci. Cras tortor nisl, pharetra sodales lobortis a, vestibulum ut libero. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Nulla facilisi. Pellentesque rutrum urna elit, sed cursus felis placerat efficitur. Curabitur tempor velit magna, mollis malesuada risus lacinia sed. Mauris tristique id mi et cursus. Quisque consectetur velit in lacus euismod scelerisque. Vestibulum ac malesuada libero, eget auctor turpis. Integer pellentesque a ipsum non faucibus. Quisque ultricies sapien ut tellus bibendum aliquam.</div>

<div class='clamp3 mb-3'>Cras vel ligula a elit pretium convallis. Nunc ac nisl nisi. Vestibulum ut ullamcorper nibh. Phasellus dictum nisi quis ullamcorper finibus. Phasellus fringilla purus ut augue varius vulputate. Nullam nec nisl dignissim, varius sem pretium, commodo orci. Cras tortor nisl, pharetra sodales lobortis a, vestibulum ut libero. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Nulla facilisi. Pellentesque rutrum urna elit, sed cursus felis placerat efficitur. Curabitur tempor velit magna, mollis malesuada risus lacinia sed. Mauris tristique id mi et cursus. Quisque consectetur velit in lacus euismod scelerisque. Vestibulum ac malesuada libero, eget auctor turpis. Integer pellentesque a ipsum non faucibus. Quisque ultricies sapien ut tellus bibendum aliquam.</div>

Javascript

/*!
* Clamp.js 0.5.1
*
* Copyright 2011-2013, Joseph Schmitt http://joe.sh
* Released under the WTFPL license
* http://sam.zoy.org/wtfpl/
*/

(function(){
    /**
     * Clamps a text node.
     * @param {HTMLElement} element. Element containing the text node to clamp.
     * @param {Object} options. Options to pass to the clamper.
     */
    function clamp(element, options) {
        options = options || {};

        var self = this,
            win = window,
            opt = {
                clamp:              options.clamp || 2,
                useNativeClamp:     typeof(options.useNativeClamp) != 'undefined' ? options.useNativeClamp : true,
                splitOnChars:       options.splitOnChars || ['.', '-', '–', '—', ' '], //Split on sentences (periods), hypens, en-dashes, em-dashes, and words (spaces).
                animate:            options.animate || false,
                truncationChar:     options.truncationChar || '…',
                truncationHTML:     options.truncationHTML
            },

            sty = element.style,
            originalText = element.innerHTML,

            supportsNativeClamp = typeof(element.style.webkitLineClamp) != 'undefined',
            clampValue = opt.clamp,
            isCSSValue = clampValue.indexOf && (clampValue.indexOf('px') > -1 || clampValue.indexOf('em') > -1),
            truncationHTMLContainer;
            
        if (opt.truncationHTML) {
            truncationHTMLContainer = document.createElement('span');
            truncationHTMLContainer.innerHTML = opt.truncationHTML;
        }


// UTILITY FUNCTIONS __________________________________________________________

        /**
         * Return the current style for an element.
         * @param {HTMLElement} elem The element to compute.
         * @param {string} prop The style property.
         * @returns {number}
         */
        function computeStyle(elem, prop) {
            if (!win.getComputedStyle) {
                win.getComputedStyle = function(el, pseudo) {
                    this.el = el;
                    this.getPropertyValue = function(prop) {
                        var re = /(\-([a-z]){1})/g;
                        if (prop == 'float') prop = 'styleFloat';
                        if (re.test(prop)) {
                            prop = prop.replace(re, function () {
                                return arguments[2].toUpperCase();
                            });
                        }
                        return el.currentStyle && el.currentStyle[prop] ? el.currentStyle[prop] : null;
                    }
                    return this;
                }
            }

            return win.getComputedStyle(elem, null).getPropertyValue(prop);
        }

        /**
         * Returns the maximum number of lines of text that should be rendered based
         * on the current height of the element and the line-height of the text.
         */
        function getMaxLines(height) {
            var availHeight = height || element.clientHeight,
                lineHeight = getLineHeight(element);

            return Math.max(Math.floor(availHeight/lineHeight), 0);
        }

        /**
         * Returns the maximum height a given element should have based on the line-
         * height of the text and the given clamp value.
         */
        function getMaxHeight(clmp) {
            var lineHeight = getLineHeight(element);
            return lineHeight * clmp;
        }

        /**
         * Returns the line-height of an element as an integer.
         */
        function getLineHeight(elem) {
            var lh = computeStyle(elem, 'line-height');
            if (lh == 'normal') {
                // Normal line heights vary from browser to browser. The spec recommends
                // a value between 1.0 and 1.2 of the font size. Using 1.1 to split the diff.
                lh = parseInt(computeStyle(elem, 'font-size')) * 1.2;
            }
            return parseInt(lh);
        }


// MEAT AND POTATOES (MMMM, POTATOES...) ______________________________________
        var splitOnChars = opt.splitOnChars.slice(0),
            splitChar = splitOnChars[0],
            chunks,
            lastChunk;
        
        /**
         * Gets an element's last child. That may be another node or a node's contents.
         */
        function getLastChild(elem) {
            //Current element has children, need to go deeper and get last child as a text node
            if (elem.lastChild.children && elem.lastChild.children.length > 0) {
                return getLastChild(Array.prototype.slice.call(elem.children).pop());
            }
            //This is the absolute last child, a text node, but something's wrong with it. Remove it and keep trying
            else if (!elem.lastChild || !elem.lastChild.nodeValue || elem.lastChild.nodeValue == '' || elem.lastChild.nodeValue == opt.truncationChar) {
                elem.lastChild.parentNode.removeChild(elem.lastChild);
                return getLastChild(element);
            }
            //This is the last child we want, return it
            else {
                return elem.lastChild;
            }
        }
        
        /**
         * Removes one character at a time from the text until its width or
         * height is beneath the passed-in max param.
         */
        function truncate(target, maxHeight) {
            if (!maxHeight) {return;}
            
            /**
             * Resets global variables.
             */
            function reset() {
                splitOnChars = opt.splitOnChars.slice(0);
                splitChar = splitOnChars[0];
                chunks = null;
                lastChunk = null;
            }
            
            var nodeValue = target.nodeValue.replace(opt.truncationChar, '');
            
            //Grab the next chunks
            if (!chunks) {
                //If there are more characters to try, grab the next one
                if (splitOnChars.length > 0) {
                    splitChar = splitOnChars.shift();
                }
                //No characters to chunk by. Go character-by-character
                else {
                    splitChar = '';
                }
                
                chunks = nodeValue.split(splitChar);
            }
            
            //If there are chunks left to remove, remove the last one and see if
            // the nodeValue fits.
            if (chunks.length > 1) {
                // console.log('chunks', chunks);
                lastChunk = chunks.pop();
                // console.log('lastChunk', lastChunk);
                applyEllipsis(target, chunks.join(splitChar));
            }
            //No more chunks can be removed using this character
            else {
                chunks = null;
            }
            
            //Insert the custom HTML before the truncation character
            if (truncationHTMLContainer) {
                target.nodeValue = target.nodeValue.replace(opt.truncationChar, '');
                element.innerHTML = target.nodeValue + ' ' + truncationHTMLContainer.innerHTML + opt.truncationChar;
            }

            //Search produced valid chunks
            if (chunks) {
                //It fits
                if (element.clientHeight <= maxHeight) {
                    //There's still more characters to try splitting on, not quite done yet
                    if (splitOnChars.length >= 0 && splitChar != '') {
                        applyEllipsis(target, chunks.join(splitChar) + splitChar + lastChunk);
                        chunks = null;
                    }
                    //Finished!
                    else {
                        return element.innerHTML;
                    }
                }
            }
            //No valid chunks produced
            else {
                //No valid chunks even when splitting by letter, time to move
                //on to the next node
                if (splitChar == '') {
                    applyEllipsis(target, '');
                    target = getLastChild(element);
                    
                    reset();
                }
            }
            
            //If you get here it means still too big, let's keep truncating
            if (opt.animate) {
                setTimeout(function() {
                    truncate(target, maxHeight);
                }, opt.animate === true ? 10 : opt.animate);
            }
            else {
                return truncate(target, maxHeight);
            }
        }
        
        function applyEllipsis(elem, str) {
            elem.nodeValue = str + opt.truncationChar;
        }


// CONSTRUCTOR ________________________________________________________________

        if (clampValue == 'auto') {
            clampValue = getMaxLines();
        }
        else if (isCSSValue) {
            clampValue = getMaxLines(parseInt(clampValue));
        }

        var clampedText;
        if (supportsNativeClamp && opt.useNativeClamp) {
            sty.overflow = 'hidden';
            sty.textOverflow = 'ellipsis';
            sty.webkitBoxOrient = 'vertical';
            sty.display = '-webkit-box';
            sty.webkitLineClamp = clampValue;

            if (isCSSValue) {
                sty.height = opt.clamp + 'px';
            }
        }
        else {
            var height = getMaxHeight(clampValue);
            if (height <= element.clientHeight) {
                clampedText = truncate(getLastChild(element), height);
            }
        }
        
        return {
            'original': originalText,
            'clamped': clampedText
        }
    }

    window.$clamp = clamp;
})();

$(document).ready(function(){

	$clamp(clamp1, {clamp: 1});

	$clamp(clamp2, {clamp: 3});
	
	$clamp(clamp3, {clamp: '100px'});
});