Data based orientations in SVG Gradients - Final example - Avenger Movie Collaborations

.block

height: 1000

README.md

This Chord diagram shows the final result of the example used in my blog on Data-based orientations for gradients in a d3.js Chord Diagram

What you see here are movie collaborations between the Avengers in the MCU (up until & including Thor Ragnarok). Because collaborations are symmetrical, the chords are all as thick at the beginnen as at the end. Therefore, I wanted each chord to represent both the Avengers that it connects through a gradient. Because all the chords run in different directions, I had to set up the orientation of each gradient by using the chord.chords() dataset

In this end result I've made the Avenger names wrap around the arcs (as explained in another blog on Placing Texts on Arcs with D3.js ) and added a simple tooltip on a hover

You can find the steps leading up to this one here

• Step 1 A normal Chord diagram with the Avengers dataset
• Step 2 A Chord diagram with gradients running across the chords
• Step 3 A Chord diagram where a custom chord ordering is applied to reduce overlap

bootstrap.popover.js

/* ========================================================================
 * Bootstrap: popover.js v3.1.1
 * http://getbootstrap.com/javascript/#popovers
 * ========================================================================
 * Copyright 2011-2014 Twitter, Inc.
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 * ======================================================================== */


+function ($) {
  'use strict';

  // POPOVER PUBLIC CLASS DEFINITION
  // ===============================

  var Popover = function (element, options) {
    this.init('popover', element, options)
  }

  if (!$.fn.tooltip) throw new Error('Popover requires tooltip.js')

  Popover.DEFAULTS = $.extend({}, $.fn.tooltip.Constructor.DEFAULTS, {
    placement: 'right',
    trigger: 'click',
    content: '',
    template: '<div class="popover"><div class="arrow"></div><h3 class="popover-title"></h3><div class="popover-content"></div></div>'
  })


  // NOTE: POPOVER EXTENDS tooltip.js
  // ================================

  Popover.prototype = $.extend({}, $.fn.tooltip.Constructor.prototype)

  Popover.prototype.constructor = Popover

  Popover.prototype.getDefaults = function () {
    return Popover.DEFAULTS
  }

  Popover.prototype.setContent = function () {
    var $tip    = this.tip()
    var title   = this.getTitle()
    var content = this.getContent()

    $tip.find('.popover-title')[this.options.html ? 'html' : 'text'](title)
    $tip.find('.popover-content')[ // we use append for html objects to maintain js events
      this.options.html ? (typeof content == 'string' ? 'html' : 'append') : 'text'
    ](content)

    $tip.removeClass('fade top bottom left right in')

    // IE8 doesn't accept hiding via the `:empty` pseudo selector, we have to do
    // this manually by checking the contents.
    if (!$tip.find('.popover-title').html()) $tip.find('.popover-title').hide()
  }

  Popover.prototype.hasContent = function () {
    return this.getTitle() || this.getContent()
  }

  Popover.prototype.getContent = function () {
    var $e = this.$element
    var o  = this.options

    return $e.attr('data-content')
      || (typeof o.content == 'function' ?
            o.content.call($e[0]) :
            o.content)
  }

  Popover.prototype.arrow = function () {
    return this.$arrow = this.$arrow || this.tip().find('.arrow')
  }

  Popover.prototype.tip = function () {
    if (!this.$tip) this.$tip = $(this.options.template)
    return this.$tip
  }


  // POPOVER PLUGIN DEFINITION
  // =========================

  var old = $.fn.popover

  $.fn.popover = function (option) {
    return this.each(function () {
      var $this   = $(this)
      var data    = $this.data('bs.popover')
      var options = typeof option == 'object' && option

      if (!data && option == 'destroy') return
      if (!data) $this.data('bs.popover', (data = new Popover(this, options)))
      if (typeof option == 'string') data[option]()
    })
  }

  $.fn.popover.Constructor = Popover


  // POPOVER NO CONFLICT
  // ===================

  $.fn.popover.noConflict = function () {
    $.fn.popover = old
    return this
  }

}(jQuery);

bootstrap.tooltip.js

/* ========================================================================
 * Bootstrap: tooltip.js v3.1.1
 * http://getbootstrap.com/javascript/#tooltip
 * Inspired by the original jQuery.tipsy by Jason Frame
 * ========================================================================
 * Copyright 2011-2014 Twitter, Inc.
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 * ======================================================================== */


+function ($) {
  'use strict';

  // TOOLTIP PUBLIC CLASS DEFINITION
  // ===============================

  var Tooltip = function (element, options) {
    this.type       =
    this.options    =
    this.enabled    =
    this.timeout    =
    this.hoverState =
    this.$measure   = 
    this.$element   = null
    
    this.init('tooltip', element, options)
  }

  Tooltip.DEFAULTS = {
    animation: true,
    mouseOffset: 0,
    measure: false,
    followMouse: false,
    placement: 'top',
    selector: false,
    template: '<div class="tooltip"><div class="tooltip-arrow"></div><div class="tooltip-inner"></div></div>',
    trigger: 'hover focus',
    title: '',
    delay: 0,
    html: false,
    container: false
  }

  Tooltip.prototype.init = function (type, element, options) {
    this.enabled  = true
    this.type     = type
    this.$element = $(element)
    this.options  = this.getOptions(options)

    if (this.options.measure) {
      this.$measure = $(this.options.measure)
    }

    var triggers = this.options.trigger.split(' ')

    for (var i = triggers.length; i--;) {
      var trigger = triggers[i]

      if (trigger == 'click') {
        this.$element.on('click.' + this.type, this.options.selector, $.proxy(this.toggle, this))
      } else if (trigger != 'manual') {
        var eventIn  = trigger == 'hover' ? 'mouseenter' : 'focusin'
        var eventOut = trigger == 'hover' ? 'mouseleave' : 'focusout'

        this.$element.on(eventIn  + '.' + this.type, this.options.selector, $.proxy(this.enter, this))
        this.$element.on(eventOut + '.' + this.type, this.options.selector, $.proxy(this.leave, this))
      }
    }

    this.options.selector ?
      (this._options = $.extend({}, this.options, { trigger: 'manual', selector: '' })) :
      this.fixTitle()
  }

  Tooltip.prototype.getDefaults = function () {
    return Tooltip.DEFAULTS
  }

  Tooltip.prototype.getOptions = function (options) {
    options = $.extend({}, this.getDefaults(), this.$element.data(), options)

    if (options.delay && typeof options.delay == 'number') {
      options.delay = {
        show: options.delay,
        hide: options.delay
      }
    }

    return options
  }

  Tooltip.prototype.getDelegateOptions = function () {
    var options  = {}
    var defaults = this.getDefaults()

    this._options && $.each(this._options, function (key, value) {
      if (defaults[key] != value) options[key] = value
    })

    return options
  }

  Tooltip.prototype.enter = function (obj) {
    var self = obj instanceof this.constructor ?
      obj : $(obj.currentTarget)[this.type](this.getDelegateOptions()).data('bs.' + this.type)

    clearTimeout(self.timeout)

    self.hoverState = 'in'

    if (!self.options.delay || !self.options.delay.show) return self.show()

    self.timeout = setTimeout(function () {
      if (self.hoverState == 'in') self.show()
    }, self.options.delay.show)
  }

  Tooltip.prototype.leave = function (obj) {
    var self = obj instanceof this.constructor ?
      obj : $(obj.currentTarget)[this.type](this.getDelegateOptions()).data('bs.' + this.type)

    clearTimeout(self.timeout)

    self.hoverState = 'out'

    if (!self.options.delay || !self.options.delay.hide) return self.hide()

    self.timeout = setTimeout(function () {
      if (self.hoverState == 'out') self.hide()
    }, self.options.delay.hide)
  }

  Tooltip.prototype.show = function () {
    var e = $.Event('show.bs.' + this.type)

    if (this.hasContent() && this.enabled) {
      this.$element.trigger(e)

      if (e.isDefaultPrevented()) return
      var that = this;

      var $tip = this.tip()

      this.setContent()

      if (this.options.animation) $tip.addClass('fade')

      var placement = typeof this.options.placement == 'function' ?
        this.options.placement.call(this, $tip[0], this.$element[0]) :
        this.options.placement

      var autoToken = /\s?auto?\s?/i
      var autoPlace = autoToken.test(placement)
      if (autoPlace) placement = placement.replace(autoToken, '') || 'top'

      $tip
        .detach()
        .css({ top: 0, left: 0, display: 'block' })
        .addClass(placement)

      this.options.container ? $tip.appendTo(this.options.container) : $tip.insertAfter(this.$element)

      var pos          = this.getPosition()
      var actualWidth  = $tip[0].offsetWidth
      var actualHeight = $tip[0].offsetHeight

      if (autoPlace) {
        placement = this.getAutoPlace($tip, placement, pos, actualWidth, actualHeight)
      }

      var calculatedOffset = this.getCalculatedOffset(placement, pos, actualWidth, actualHeight)

      this.applyPlacement(calculatedOffset, placement)
      this.hoverState = null

      var complete = function() {
        that.$element.trigger('shown.bs.' + that.type)
      }

      if (this.options.followMouse) {
        $(this.options.container).on('mousemove', $.proxy(this.follow, this));
      }

      $.support.transition && this.$tip.hasClass('fade') ?
        $tip
          .one($.support.transition.end, complete)
          .emulateTransitionEnd(150) :
        complete()
    }
  }

  Tooltip.prototype.getAutoPlace = function($tip, placement, pos, actualWidth, actualHeight) {

    var $parent = this.$element.parent()

    var orgPlacement = placement
    var docScroll    = document.documentElement.scrollTop || document.body.scrollTop
    var parentWidth  = this.options.container == 'body' ? window.innerWidth  : $parent.outerWidth()
    var parentHeight = this.options.container == 'body' ? window.innerHeight : $parent.outerHeight()
    var parentLeft   = this.options.container == 'body' ? 0 : $parent.offset().left

    placement = placement == 'bottom' && pos.top   + pos.height  + actualHeight - docScroll > parentHeight  ? 'top'    :
                placement == 'top'    && pos.top   - docScroll   - actualHeight < 0                         ? 'bottom' :
                placement == 'right'  && pos.left  + actualWidth > parentWidth                              ? 'left'   :
                placement == 'left'   && pos.left  - actualWidth < parentLeft                               ? 'right'  :
                placement

    $tip
      .removeClass(orgPlacement)
      .addClass(placement)

    return placement
  }

  Tooltip.prototype.follow = function(e) {
    
    var $tip = this.tip()

    var pos          = this.getPosition()
    var actualWidth  = $tip[0].offsetWidth
    var actualHeight = $tip[0].offsetHeight

    var placement = typeof this.options.placement == 'function' ?
        this.options.placement.call(this, $tip[0], this.$element[0]) :
        this.options.placement

      var autoToken = /\s?auto?\s?/i
      var autoPlace = autoToken.test(placement)
      if (autoPlace) placement = placement.replace(autoToken, '') || 'top'

    pos.left = e.pageX + this.options.mouseOffset;
    pos.top = e.pageY + this.options.mouseOffset;

    var placement = this.getAutoPlace($tip, placement, pos, actualWidth, actualHeight)
    var calculatedOffset = this.getCalculatedOffset(placement, pos, actualWidth, actualHeight, e)

    this.applyPlacement(calculatedOffset, placement)
  }

  Tooltip.prototype.applyPlacement = function (offset, placement) {
    var replace
    var $tip   = this.tip()
    var width  = $tip[0].offsetWidth
    var height = $tip[0].offsetHeight

    // manually read margins because getBoundingClientRect includes difference
    var marginTop = parseInt($tip.css('margin-top'), 10)
    var marginLeft = parseInt($tip.css('margin-left'), 10)

    // we must check for NaN for ie 8/9
    if (isNaN(marginTop))  marginTop  = 0
    if (isNaN(marginLeft)) marginLeft = 0

    offset.top  = offset.top  + marginTop
    offset.left = offset.left + marginLeft

    // $.fn.offset doesn't round pixel values
    // so we use setOffset directly with our own function B-0
    $.offset.setOffset($tip[0], $.extend({
      using: function (props) {
        $tip.css({
          top: Math.round(props.top),
          left: Math.round(props.left)
        })
      }
    }, offset), 0)

    $tip.addClass('in')

    // check to see if placing tip in new offset caused the tip to resize itself
    var actualWidth  = $tip[0].offsetWidth
    var actualHeight = $tip[0].offsetHeight

    if (placement == 'top' && actualHeight != height) {
      replace = true
      offset.top = offset.top + height - actualHeight
    }

    if (/bottom|top/.test(placement)) {
      var delta = 0

      if (offset.left < 0) {
        delta       = offset.left * -2
        offset.left = 0

        $tip.offset(offset)

        actualWidth  = $tip[0].offsetWidth
        actualHeight = $tip[0].offsetHeight
      }

      this.replaceArrow(delta - width + actualWidth, actualWidth, 'left')
    } else {
      this.replaceArrow(actualHeight - height, actualHeight, 'top')
    }

    if (replace) $tip.offset(offset)
  }

  Tooltip.prototype.replaceArrow = function (delta, dimension, position) {

    if(this.options.mouseOffset > 0 && position === 'top') {
      this.arrow().css(position, this.options.mouseOffset + 10 + 'px')
      return;
    }

    this.arrow().css(position, delta ? (50 * (1 - delta / dimension) + '%') : '')
  }

  Tooltip.prototype.setContent = function () {
    var $tip  = this.tip()
    var title = this.getTitle()

    $tip.find('.tooltip-inner')[this.options.html ? 'html' : 'text'](title)
    $tip.removeClass('fade in top bottom left right')
  }

  Tooltip.prototype.hide = function () {
    var that = this
    var $tip = this.tip()
    var e    = $.Event('hide.bs.' + this.type)

    function complete() {
      if (that.hoverState != 'in') $tip.detach()
      that.$element.trigger('hidden.bs.' + that.type)
    }

    $(this.options.container).off('mousemove');
    this.$element.trigger(e)

    if (e.isDefaultPrevented()) return

    $tip.removeClass('in')

    $.support.transition && this.$tip.hasClass('fade') ?
      $tip
        .one($.support.transition.end, complete)
        .emulateTransitionEnd(150) :
      complete()

    this.hoverState = null

    return this
  }

  Tooltip.prototype.fixTitle = function () {
    var $e = this.$element
    if ($e.attr('title') || typeof($e.attr('data-original-title')) != 'string') {
      $e.attr('data-original-title', $e.attr('title') || '').attr('title', '')
    }
  }

  Tooltip.prototype.hasContent = function () {
    return this.getTitle()
  }

  Tooltip.prototype.getPosition = function () {
    
    var el = this.$element[0]
    if(this.$element.prop('tagName') == 'AREA') {

      var position = this.$element.attr('coords').split(',');
      var x = parseInt(position[0], 0) + parseInt(this.$measure.offset().left, 0);
      var y = parseInt(position[1], 0) + parseInt(this.$measure.offset().top, 0);

      return {bottom: 0, height: el.offsetWidth, left: x, right: 0, top: y, width: el.offsetWidth}
    }

    return $.extend({}, (typeof el.getBoundingClientRect == 'function') ? el.getBoundingClientRect() : {
      width: el.offsetWidth,
      height: el.offsetHeight
    }, this.$element.offset())
  }

  Tooltip.prototype.getCalculatedOffset = function (placement, pos, actualWidth, actualHeight, follow) {
    
    if (typeof follow !== 'undefined') {

      return  placement == 'bottom' ? { top: follow.pageY + this.options.mouseOffset, left: follow.pageX - (actualWidth / 2)  } :
              placement == 'top'    ? { top: follow.pageY - actualHeight - this.options.mouseOffset, left: follow.pageX - (actualWidth / 2)  } :
              placement == 'left'   ? { top: follow.pageY - this.options.mouseOffset, left: follow.pageX - (actualWidth + this.options.mouseOffset) } :
                                     { top: follow.pageY - this.options.mouseOffset, left: follow.pageX + this.options.mouseOffset }
    }

    return placement == 'bottom' ? { top: pos.top + pos.height,   left: pos.left + pos.width / 2 - actualWidth / 2  } :
           placement == 'top'    ? { top: pos.top - actualHeight, left: pos.left + pos.width / 2 - actualWidth / 2  } :
           placement == 'left'   ? { top: pos.top + pos.height / 2 - actualHeight / 2, left: pos.left - actualWidth } :
                                   { top: pos.top + pos.height / 2 - actualHeight / 2, left: pos.left + pos.width   }
  }

  Tooltip.prototype.getTitle = function () {
    var title
    var $e = this.$element
    var o  = this.options

    title = $e.attr('data-original-title')
      || (typeof o.title == 'function' ? o.title.call($e[0]) :  o.title)

    return title
  }

  Tooltip.prototype.tip = function () {
    return this.$tip = this.$tip || $(this.options.template)
  }

  Tooltip.prototype.arrow = function () {
    return this.$arrow = this.$arrow || this.tip().find('.tooltip-arrow')
  }

  Tooltip.prototype.validate = function () {
    if (!this.$element[0].parentNode) {
      this.hide()
      this.$element = null
      this.options  = null
    }
  }

  Tooltip.prototype.enable = function () {
    this.enabled = true
  }

  Tooltip.prototype.disable = function () {
    this.enabled = false
  }

  Tooltip.prototype.toggleEnabled = function () {
    this.enabled = !this.enabled
  }

  Tooltip.prototype.toggle = function (e) {
    var self = e ? $(e.currentTarget)[this.type](this.getDelegateOptions()).data('bs.' + this.type) : this
    self.tip().hasClass('in') ? self.leave(self) : self.enter(self)
  }

  Tooltip.prototype.destroy = function () {
    clearTimeout(this.timeout)
    this.hide().$element.off('.' + this.type).removeData('bs.' + this.type)
  }


  // TOOLTIP PLUGIN DEFINITION
  // =========================

  var old = $.fn.tooltip

  $.fn.tooltip = function (option) {
    return this.each(function () {
      var $this   = $(this)
      var data    = $this.data('bs.tooltip')
      var options = typeof option == 'object' && option

      if (!data && option == 'destroy') return
      if (!data) $this.data('bs.tooltip', (data = new Tooltip(this, options)))
      if (typeof option == 'string') data[option]()
    })
  }

  $.fn.tooltip.Constructor = Tooltip


  // TOOLTIP NO CONFLICT
  // ===================

  $.fn.tooltip.noConflict = function () {
    $.fn.tooltip = old
    return this
  }

}(jQuery);

d3.layout.chord.sort.js

////////////////////////////////////////////////////////////
//////////// Custom Chord Layout Function //////////////////
/////// Places the Chords in the visually best order ///////
///////////////// to reduce overlap ////////////////////////
////////////////////////////////////////////////////////////
//////// Slightly adjusted by Nadieh Bremer ////////////////
//////////////// VisualCinnamon.com ////////////////////////
////////////////////////////////////////////////////////////
////// Original from the d3.layout.chord() function ////////
///////////////// from the d3.js library ///////////////////
//////////////// Created by Mike Bostock ///////////////////
////////////////////////////////////////////////////////////

customChordLayout = function() {
	var ε = 1e-6, ε2 = ε * ε, π = Math.PI, τ = 2 * π, τε = τ - ε, halfπ = π / 2, d3_radians = π / 180, d3_degrees = 180 / π;
    var chord = {}, chords, groups, matrix, n, padding = 0, sortGroups, sortSubgroups, sortChords;
    function relayout() {
		var subgroups = {}, groupSums = [], groupIndex = d3.range(n), subgroupIndex = [], k, x, x0, i, j;
		var numSeq;
		chords = [];
		groups = [];
		k = 0, i = -1;
		  
		while (++i < n) {
			x = 0, j = -1, numSeq = [];
			while (++j < n) {
			  x += matrix[i][j];
			}
			groupSums.push(x);
			//////////////////////////////////////
			////////////// New part //////////////
			//////////////////////////////////////
			for(var m = 0; m < n; m++) {	
				numSeq[m] = (n+(i-1)-m)%n;
			}
			subgroupIndex.push(numSeq);
			//////////////////////////////////////
			//////////  End new part /////////////
			//////////////////////////////////////
			k += x;
		  }//while
	  
		k = (τ - padding * n) / k;
		x = 0, i = -1;
		while (++i < n) {
			x0 = x, j = -1;
			while (++j < n) {
				var di = groupIndex[i], dj = subgroupIndex[di][j], v = matrix[di][dj], a0 = x, a1 = x += v * k;
				subgroups[di + "-" + dj] = {
					index: di,
					subindex: dj,
					startAngle: a0,
					endAngle: a1,
					value: v
				};
			}//while
			
			groups[di] = {
				index: di,
				startAngle: x0,
				endAngle: x,
				value: (x - x0) / k
			};
			x += padding;
		}//while

		i = -1;
		while (++i < n) {
			j = i - 1;
			while (++j < n) {
				var source = subgroups[i + "-" + j], target = subgroups[j + "-" + i];
				if (source.value || target.value) {
					chords.push(source.value < target.value ? {
						source: target,
						target: source
					} : {
						source: source,
						target: target
					});
				}//if
			}//while
		}//while
      if (sortChords) resort();
    }//function relayout
	
    function resort() {
      chords.sort(function(a, b) {
        return sortChords((a.source.value + a.target.value) / 2, (b.source.value + b.target.value) / 2);
      });
    }
    chord.matrix = function(x) {
      if (!arguments.length) return matrix;
      n = (matrix = x) && matrix.length;
      chords = groups = null;
      return chord;
    };
    chord.padding = function(x) {
      if (!arguments.length) return padding;
      padding = x;
      chords = groups = null;
      return chord;
    };
    chord.sortGroups = function(x) {
      if (!arguments.length) return sortGroups;
      sortGroups = x;
      chords = groups = null;
      return chord;
    };
    chord.sortSubgroups = function(x) {
      if (!arguments.length) return sortSubgroups;
      sortSubgroups = x;
      chords = null;
      return chord;
    };
    chord.sortChords = function(x) {
      if (!arguments.length) return sortChords;
      sortChords = x;
      if (chords) resort();
      return chord;
    };
    chord.chords = function() {
      if (!chords) relayout();
      return chords;
    };
    chord.groups = function() {
      if (!groups) relayout();
      return groups;
    };
    return chord;
  };

index.html

<!DOCTYPE html>
<html>
	<head>
		<meta http-equiv="Content-Type" content="text/html;charset=utf-8"/>
		<title>Collaborations between MCU Avengers</title>
	
		<!-- D3.js -->
		<script src="//cdnjs.cloudflare.com/ajax/libs/d3/3.5.6/d3.min.js" charset="utf-8"></script>
		
		<!-- Google Fonts -->
		<link href='//fonts.googleapis.com/css?family=Bangers' rel='stylesheet' type='text/css'>
		<link href='//fonts.googleapis.com/css?family=Oswald' rel='stylesheet' type='text/css'>
		<link href='//fonts.googleapis.com/css?family=Lato:400,900' rel='stylesheet' type='text/css'>
		
		<!-- jQuery -->
		<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
		<!-- Bootstrap -->
		<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap.min.css" rel="stylesheet">
		<script src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.2/js/bootstrap.min.js"></script>
	
		<!-- Two scripts to make the Bootstrap tooltip follow the mouse movement
			 taken from //github.com/ghophp/bootstrap-popover-move -->
		<script src="bootstrap.tooltip.js"></script>
		<script src="bootstrap.popover.js"></script>
		
		<script src="d3.layout.chord.sort.js"></script>
		
		<style>
			body {
			  font-size: 14px;
			  font-family: 'Lato', sans-serif;
			  text-align: left;
			  color: #757575;
			  cursor: default;
			}
			
			.title {
				margin-top: 20px;
				margin-bottom: 10px;
				margin-left: 20px;
				font-size:32px;
				font-family: 'Oswald', sans-serif;
				color: #2B2B2B;
			}
			
			.texts {
				margin-left: 20px;
				margin-right: 20px;
				line-height: 140%;
			}
			
			.credit {
				color: #9E9E9E;
				font-size: 10px;
				margin-bottom: 0.5em;
			}
			
			.notes {
				color: #9E9E9E;
				font-size: 10px;
			}
			
			.popover {
				pointer-events: none;
			}
			
			#chart{
			  font-size: 16px;
			  font-family: 'Bangers', sans-serif;
			  text-align: center;
			  fill: #2B2B2B;
			}
			
			@media (min-width: 600px) {
				#chart{
					font-size: 20px;
				}
			}
		</style>
	</head>
	<body>
	
		<script src="script.js"></script>

  </body>
</html>

script.js

////////////////////////////////////////////////////////////
//////////////////////// Set-Up ////////////////////////////
////////////////////////////////////////////////////////////

var margin = {left:20, top:20, right:20, bottom:20},
	width = Math.min(window.innerWidth, 700) - margin.left - margin.right,
    height = Math.min(window.innerWidth, 700) - margin.top - margin.bottom,
    innerRadius = Math.min(width, height) * .39,
    outerRadius = innerRadius * 1.1;
	
var Names = ["Black Widow","Captain America","Hawkeye","the Hulk","Iron Man","Thor"],
	colors = ["#301E1E", "#083E77", "#342350", "#567235", "#8B161C", "#DF7C00"],
	opacityDefault = 0.8;

var matrix = [
	[0,4,3,2,5,2], //Black Widow
	[4,0,3,2,4,3], //Captain America
	[3,3,0,2,3,3], //Hawkeye
	[2,2,2,0,3,3], //The Hulk
	[5,4,3,3,0,2], //Iron Man
	[2,3,3,3,2,0], //Thor
];

////////////////////////////////////////////////////////////
/////////// Create scale and layout functions //////////////
////////////////////////////////////////////////////////////

var colors = d3.scale.ordinal()
    .domain(d3.range(Names.length))
	.range(colors);

//A "custom" d3 chord function that automatically sorts the order of the chords in such a manner to reduce overlap	
var chord = customChordLayout()
    .padding(.15)
    .sortChords(d3.descending) //which chord should be shown on top when chords cross. Now the biggest chord is at the bottom
	.matrix(matrix);
		
var arc = d3.svg.arc()
    .innerRadius(innerRadius*1.01)
    .outerRadius(outerRadius);

var path = d3.svg.chord()
	.radius(innerRadius);
	
////////////////////////////////////////////////////////////
////////////////////// Create SVG //////////////////////////
////////////////////////////////////////////////////////////
	
var svg = d3.select("#chart").append("svg")
    .attr("width", width + margin.left + margin.right)
    .attr("height", height + margin.top + margin.bottom)
	.append("g")
    .attr("transform", "translate(" + (width/2 + margin.left) + "," + (height/2 + margin.top) + ")");

////////////////////////////////////////////////////////////
/////////////// Create the gradient fills //////////////////
////////////////////////////////////////////////////////////

//Function to create the id for each chord gradient
function getGradID(d){ return "linkGrad-" + d.source.index + "-" + d.target.index; }

//Create the gradients definitions for each chord
var grads = svg.append("defs").selectAll("linearGradient")
	.data(chord.chords())
   .enter().append("linearGradient")
	.attr("id", getGradID)
	.attr("gradientUnits", "userSpaceOnUse")
	.attr("x1", function(d,i) { return innerRadius * Math.cos((d.source.endAngle-d.source.startAngle)/2 + d.source.startAngle - Math.PI/2); })
	.attr("y1", function(d,i) { return innerRadius * Math.sin((d.source.endAngle-d.source.startAngle)/2 + d.source.startAngle - Math.PI/2); })
	.attr("x2", function(d,i) { return innerRadius * Math.cos((d.target.endAngle-d.target.startAngle)/2 + d.target.startAngle - Math.PI/2); })
	.attr("y2", function(d,i) { return innerRadius * Math.sin((d.target.endAngle-d.target.startAngle)/2 + d.target.startAngle - Math.PI/2); })

//Set the starting color (at 0%)
grads.append("stop")
	.attr("offset", "0%")
	.attr("stop-color", function(d){ return colors(d.source.index); });

//Set the ending color (at 100%)
grads.append("stop")
	.attr("offset", "100%")
	.attr("stop-color", function(d){ return colors(d.target.index); });
		
////////////////////////////////////////////////////////////
////////////////// Draw outer Arcs /////////////////////////
////////////////////////////////////////////////////////////

var outerArcs = svg.selectAll("g.group")
	.data(chord.groups)
	.enter().append("g")
	.attr("class", "group")
	.on("mouseover", fade(.1))
	.on("mouseout", fade(opacityDefault));

outerArcs.append("path")
	.style("fill", function(d) { return colors(d.index); })
	.attr("d", arc)
	.each(function(d,i) {
		//Search pattern for everything between the start and the first capital L
		var firstArcSection = /(^.+?)L/; 	

		//Grab everything up to the first Line statement
		var newArc = firstArcSection.exec( d3.select(this).attr("d") )[1];
		//Replace all the comma's so that IE can handle it
		newArc = newArc.replace(/,/g , " ");
		
		//If the end angle lies beyond a quarter of a circle (90 degrees or pi/2) 
		//flip the end and start position
		if (d.endAngle > 90*Math.PI/180 & d.startAngle < 270*Math.PI/180) {
			var startLoc 	= /M(.*?)A/,		//Everything between the first capital M and first capital A
				middleLoc 	= /A(.*?)0 0 1/,	//Everything between the first capital A and 0 0 1
				endLoc 		= /0 0 1 (.*?)$/;	//Everything between the first 0 0 1 and the end of the string (denoted by $)
			//Flip the direction of the arc by switching the start en end point (and sweep flag)
			//of those elements that are below the horizontal line
			var newStart = endLoc.exec( newArc )[1];
			var newEnd = startLoc.exec( newArc )[1];
			var middleSec = middleLoc.exec( newArc )[1];
			
			//Build up the new arc notation, set the sweep-flag to 0
			newArc = "M" + newStart + "A" + middleSec + "0 0 0 " + newEnd;
		}//if
		
		//Create a new invisible arc that the text can flow along
		svg.append("path")
			.attr("class", "hiddenArcs")
			.attr("id", "arc"+i)
			.attr("d", newArc)
			.style("fill", "none");
	});

////////////////////////////////////////////////////////////
////////////////// Append Names ////////////////////////////
////////////////////////////////////////////////////////////

//Append the label names on the outside
outerArcs.append("text")
	.attr("class", "titles")
	.attr("dy", function(d,i) { return (d.endAngle > 90*Math.PI/180 & d.startAngle < 270*Math.PI/180 ? 25 : -16); })
   .append("textPath")
	.attr("startOffset","50%")
	.style("text-anchor","middle")
	.attr("xlink:href",function(d,i){return "#arc"+i;})
	.text(function(d,i){ return Names[i]; });
	
////////////////////////////////////////////////////////////
////////////////// Draw inner chords ///////////////////////
////////////////////////////////////////////////////////////
  
svg.selectAll("path.chord")
	.data(chord.chords)
	.enter().append("path")
	.attr("class", "chord")
	.style("fill", function(d){ return "url(#" + getGradID(d) + ")"; })
	.style("opacity", opacityDefault)
	.attr("d", path)
	.on("mouseover", mouseoverChord)
	.on("mouseout", mouseoutChord);

////////////////////////////////////////////////////////////
////////////////// Extra Functions /////////////////////////
////////////////////////////////////////////////////////////

//Returns an event handler for fading a given chord group.
function fade(opacity) {
  return function(d,i) {
    svg.selectAll("path.chord")
        .filter(function(d) { return d.source.index !== i && d.target.index !== i; })
		.transition()
        .style("opacity", opacity);
  };
}//fade

//Highlight hovered over chord
function mouseoverChord(d,i) {
  
	//Decrease opacity to all
	svg.selectAll("path.chord")
		.transition()
		.style("opacity", 0.1);
	//Show hovered over chord with full opacity
	d3.select(this)
		.transition()
        .style("opacity", 1);
  
	//Define and show the tooltip over the mouse location
	$(this).popover({
		placement: 'auto top',
		container: 'body',
		mouseOffset: 10,
		followMouse: true,
		trigger: 'hover',
		html : true,
		content: function() { 
			return "<p style='font-size: 11px; text-align: center;'><span style='font-weight:900'>" + Names[d.source.index] + 
				   "</span> and <span style='font-weight:900'>" + Names[d.target.index] + 
				   "</span> appeared together in <span style='font-weight:900'>" + d.source.value + "</span> movies </p>"; }
	});
	$(this).popover('show');
}//mouseoverChord

//Bring all chords back to default opacity
function mouseoutChord(d) {
	//Hide the tooltip
	$('.popover').each(function() {
		$(this).remove();
	}); 
	//Set opacity back to default for all
	svg.selectAll("path.chord")
		.transition()
		.style("opacity", opacityDefault);
}//function mouseoutChord

thumbnail.png