Lugo Labs

Create circular SVG charts with Circles

The circular graphs with the numerical value in the center have been a great way to visualizing data lately. For example, they are used to great effect by awwwards.

Circles makes creating the charts very easy. Circles is a lightweight JavaScript library without dependencies, that generates the SVG chart on the fly.

Create a graph by calling:

js
Circles.create({
  id:           'circles-1',
  radius:       60,
  value:        43,
  maxValue:     100,
  width:        10,
  text:         function(value){return value + '%';},
  colors:       ['#D3B6C6', '#4B253A'],
  duration:     400,
  wrpClass:     'circles-wrp',
  textClass:    'circles-text'
  styleWrapper: true,
  styleText:    true
})

where

  • id - the DOM element that will hold the graph
  • radius - the radius of the circles
  • value - init value of the circle (optional, defaults to 0)
  • maxValue - maximum value of the circle (optional, defaults to 100)
  • width - the width of the ring (optional, has value 10, if not specified)
  • colors - an array of colors, with the first item coloring the full circle (optional, it will be ['#EEE', '#F00'] if not specified)
  • duration - value in ms of animation's duration; defaults to 500; if 0 or null is passed, the animation will not run.
  • wrpClass - class name to apply on the generated element wrapping the whole circle.
  • textClass - class name to apply on the generated element wrapping the text content.
  • styleWrapper - whether or not to add inline styles to the wrapper element (defaults to true)
  • styleText - whether or not to add inline styles to the text (defaults to true)
  • text - the text to display at the center of the graph (optional, the current "htmlified" value will be shown); if null or an empty string, no text will be displayed; it can also be a function: the returned value will be the displayed text:
js
// Example 1
function(currentValue) {
  return '$'+currentValue;
}
// Example 2
function() {
  return this.getPercent() + '%';
}

API

js
myCircle.updateRadius(Number radius)

Regenerates the circle with the given radius (see spec/responsive.html for an example on how to create a responsive circle).

js
myCircle.updateWidth(Number width)

Regenerates the circle with the given width

js
myCircle.updateColors(Array colors)

Change colors used to draw the circle.

js
myCircle.update(Number value [, Number duration])

Set the value of the circle to value. Animation will take duration ms to execute. If no duration is given, default duration set in constructor will be used. If you don't want animation, set duration to 0.

js
myCircle.update(Boolean force)

Force the redrawing of the circle if force is set to true. Do nothing otherwise.

js
myCircle.getPercent()

Returns the percentage value of the circle, based on its current value and its max value.

js
myCircle.getValue()

Returns the value of the circle.

js
myCircle.getMaxValue()

Returns the max value of the circle.

js
myCircle.getValueFromPercent(Number percentage)

Returns the corresponding value of the circle based on its max value and given percentage.

js
myCircle.htmlifyNumber(Number number[, integerPartClass, decimalPartClass])

Returned HTML representation of given number with given classes names applied on tags. Default value of integerPartClass is circles-integer. Default value of decimalPartClass is circles-decimals.

Styles

The styles have been specified inline to avoid external dependencies. But they can be overriden via CSS easily, being simply HTML elements.

To help with this, a few CSS classes have been exposed:

  • circles-wrp - the element wrapping the whole circle
  • circles-text - the element wrapping text content

You can overwritte these classes by sending properties wrpClass and/or textClass to the constructor.

HTML

Circles produces the minimum HTML needed to show the graph.

html
<div class="circles-wrp" style="position: relative; display: inline-block;">
  <svg xmlns="http://www.w3.org/2000/svg" width="80" height="80">
    <path fill="transparent" stroke="#D3B6C6" stroke-width="7" d="M 39.992565928065126 3.500000757060633 A 36.5 36.5 0 1 1 39.949302232260386 3.500035209108127 Z"></path>
    <path fill="transparent" stroke="#4B253A" stroke-width="7" d="M 39.992565928065126 3.500000757060633 A 36.5 36.5 0 0 1 59.07174573163989 71.12103010421852 "></path>
  </svg>
  <div class="circles-text" style="position: absolute; top: 0px; left: 0px; text-align: center; width: 100%; font-size: 28px; height: 80px; line-height: 80px;">
    <span class="circles-integer">41</span>.
    <span class="circles-decimals">26</span>
  </div>
</div>

The SVG consists of two paths, one of wich is the full circle, with usually a paler color. The other path generates the smaller, strngly colored ring.

The text is contained inside a DIV element with the decimal value split inside a SPAN for better style control.

The whole content is then wrapped inside a self-contained DIV.

Styles

The styles have been specified inline to avoid external dependencies. But they can be overriden via CSS easily, being simply HTML elements.

To help with this, a few CSS classes have been exposed:

  • circles-wrp - the element wrapping the whole circle
  • circles-text - the element wrapping text content
  • circles-integer - the element wrapping the text before the dot
  • circles-decimals - the element wrapping the decimal places

You can overwritte these classes by sending properties wrpClass and/or textClass to the constructor.

Compatibility

Browsers that support SVG.

Desktop Firefox 3+, Chrome 4+, Safari 3.2+, Opera 9+, IE9 +

Mobile iOS Safari 3.2+, Android Browser 3+, Opera Mobile 10+, Chrome for Android 18+, Firefox for Android 15+

Inspirations

Code and ideas have been borrowed from Highcharts and Wout Fierens's svg.js.