xref: /minix/minix/share/beaglebone/weather/spin.js (revision 7f5f010b)
1//fgnass.github.com/spin.js#v1.3.2
2
3/**
4 * Copyright (c) 2011-2013 Felix Gnass
5 * Licensed under the MIT license
6 */
7(function(root, factory) {
8
9  /* CommonJS */
10  if (typeof exports == 'object')  module.exports = factory()
11
12  /* AMD module */
13  else if (typeof define == 'function' && define.amd) define(factory)
14
15  /* Browser global */
16  else root.Spinner = factory()
17}
18(this, function() {
19  "use strict";
20
21  var prefixes = ['webkit', 'Moz', 'ms', 'O'] /* Vendor prefixes */
22    , animations = {} /* Animation rules keyed by their name */
23    , useCssAnimations /* Whether to use CSS animations or setTimeout */
24
25  /**
26   * Utility function to create elements. If no tag name is given,
27   * a DIV is created. Optionally properties can be passed.
28   */
29  function createEl(tag, prop) {
30    var el = document.createElement(tag || 'div')
31      , n
32
33    for(n in prop) el[n] = prop[n]
34    return el
35  }
36
37  /**
38   * Appends children and returns the parent.
39   */
40  function ins(parent /* child1, child2, ...*/) {
41    for (var i=1, n=arguments.length; i<n; i++)
42      parent.appendChild(arguments[i])
43
44    return parent
45  }
46
47  /**
48   * Insert a new stylesheet to hold the @keyframe or VML rules.
49   */
50  var sheet = (function() {
51    var el = createEl('style', {type : 'text/css'})
52    ins(document.getElementsByTagName('head')[0], el)
53    return el.sheet || el.styleSheet
54  }())
55
56  /**
57   * Creates an opacity keyframe animation rule and returns its name.
58   * Since most mobile Webkits have timing issues with animation-delay,
59   * we create separate rules for each line/segment.
60   */
61  function addAnimation(alpha, trail, i, lines) {
62    var name = ['opacity', trail, ~~(alpha*100), i, lines].join('-')
63      , start = 0.01 + i/lines * 100
64      , z = Math.max(1 - (1-alpha) / trail * (100-start), alpha)
65      , prefix = useCssAnimations.substring(0, useCssAnimations.indexOf('Animation')).toLowerCase()
66      , pre = prefix && '-' + prefix + '-' || ''
67
68    if (!animations[name]) {
69      sheet.insertRule(
70        '@' + pre + 'keyframes ' + name + '{' +
71        '0%{opacity:' + z + '}' +
72        start + '%{opacity:' + alpha + '}' +
73        (start+0.01) + '%{opacity:1}' +
74        (start+trail) % 100 + '%{opacity:' + alpha + '}' +
75        '100%{opacity:' + z + '}' +
76        '}', sheet.cssRules.length)
77
78      animations[name] = 1
79    }
80
81    return name
82  }
83
84  /**
85   * Tries various vendor prefixes and returns the first supported property.
86   */
87  function vendor(el, prop) {
88    var s = el.style
89      , pp
90      , i
91
92    prop = prop.charAt(0).toUpperCase() + prop.slice(1)
93    for(i=0; i<prefixes.length; i++) {
94      pp = prefixes[i]+prop
95      if(s[pp] !== undefined) return pp
96    }
97    if(s[prop] !== undefined) return prop
98  }
99
100  /**
101   * Sets multiple style properties at once.
102   */
103  function css(el, prop) {
104    for (var n in prop)
105      el.style[vendor(el, n)||n] = prop[n]
106
107    return el
108  }
109
110  /**
111   * Fills in default values.
112   */
113  function merge(obj) {
114    for (var i=1; i < arguments.length; i++) {
115      var def = arguments[i]
116      for (var n in def)
117        if (obj[n] === undefined) obj[n] = def[n]
118    }
119    return obj
120  }
121
122  /**
123   * Returns the absolute page-offset of the given element.
124   */
125  function pos(el) {
126    var o = { x:el.offsetLeft, y:el.offsetTop }
127    while((el = el.offsetParent))
128      o.x+=el.offsetLeft, o.y+=el.offsetTop
129
130    return o
131  }
132
133  /**
134   * Returns the line color from the given string or array.
135   */
136  function getColor(color, idx) {
137    return typeof color == 'string' ? color : color[idx % color.length]
138  }
139
140  // Built-in defaults
141
142  var defaults = {
143    lines: 12,            // The number of lines to draw
144    length: 7,            // The length of each line
145    width: 5,             // The line thickness
146    radius: 10,           // The radius of the inner circle
147    rotate: 0,            // Rotation offset
148    corners: 1,           // Roundness (0..1)
149    color: '#000',        // #rgb or #rrggbb
150    direction: 1,         // 1: clockwise, -1: counterclockwise
151    speed: 1,             // Rounds per second
152    trail: 100,           // Afterglow percentage
153    opacity: 1/4,         // Opacity of the lines
154    fps: 20,              // Frames per second when using setTimeout()
155    zIndex: 2e9,          // Use a high z-index by default
156    className: 'spinner', // CSS class to assign to the element
157    top: 'auto',          // center vertically
158    left: 'auto',         // center horizontally
159    position: 'relative'  // element position
160  }
161
162  /** The constructor */
163  function Spinner(o) {
164    if (typeof this == 'undefined') return new Spinner(o)
165    this.opts = merge(o || {}, Spinner.defaults, defaults)
166  }
167
168  // Global defaults that override the built-ins:
169  Spinner.defaults = {}
170
171  merge(Spinner.prototype, {
172
173    /**
174     * Adds the spinner to the given target element. If this instance is already
175     * spinning, it is automatically removed from its previous target b calling
176     * stop() internally.
177     */
178    spin: function(target) {
179      this.stop()
180
181      var self = this
182        , o = self.opts
183        , el = self.el = css(createEl(0, {className: o.className}), {position: o.position, width: 0, zIndex: o.zIndex})
184        , mid = o.radius+o.length+o.width
185        , ep // element position
186        , tp // target position
187
188      if (target) {
189        target.insertBefore(el, target.firstChild||null)
190        tp = pos(target)
191        ep = pos(el)
192        css(el, {
193          left: (o.left == 'auto' ? tp.x-ep.x + (target.offsetWidth >> 1) : parseInt(o.left, 10) + mid) + 'px',
194          top: (o.top == 'auto' ? tp.y-ep.y + (target.offsetHeight >> 1) : parseInt(o.top, 10) + mid)  + 'px'
195        })
196      }
197
198      el.setAttribute('role', 'progressbar')
199      self.lines(el, self.opts)
200
201      if (!useCssAnimations) {
202        // No CSS animation support, use setTimeout() instead
203        var i = 0
204          , start = (o.lines - 1) * (1 - o.direction) / 2
205          , alpha
206          , fps = o.fps
207          , f = fps/o.speed
208          , ostep = (1-o.opacity) / (f*o.trail / 100)
209          , astep = f/o.lines
210
211        ;(function anim() {
212          i++;
213          for (var j = 0; j < o.lines; j++) {
214            alpha = Math.max(1 - (i + (o.lines - j) * astep) % f * ostep, o.opacity)
215
216            self.opacity(el, j * o.direction + start, alpha, o)
217          }
218          self.timeout = self.el && setTimeout(anim, ~~(1000/fps))
219        })()
220      }
221      return self
222    },
223
224    /**
225     * Stops and removes the Spinner.
226     */
227    stop: function() {
228      var el = this.el
229      if (el) {
230        clearTimeout(this.timeout)
231        if (el.parentNode) el.parentNode.removeChild(el)
232        this.el = undefined
233      }
234      return this
235    },
236
237    /**
238     * Internal method that draws the individual lines. Will be overwritten
239     * in VML fallback mode below.
240     */
241    lines: function(el, o) {
242      var i = 0
243        , start = (o.lines - 1) * (1 - o.direction) / 2
244        , seg
245
246      function fill(color, shadow) {
247        return css(createEl(), {
248          position: 'absolute',
249          width: (o.length+o.width) + 'px',
250          height: o.width + 'px',
251          background: color,
252          boxShadow: shadow,
253          transformOrigin: 'left',
254          transform: 'rotate(' + ~~(360/o.lines*i+o.rotate) + 'deg) translate(' + o.radius+'px' +',0)',
255          borderRadius: (o.corners * o.width>>1) + 'px'
256        })
257      }
258
259      for (; i < o.lines; i++) {
260        seg = css(createEl(), {
261          position: 'absolute',
262          top: 1+~(o.width/2) + 'px',
263          transform: o.hwaccel ? 'translate3d(0,0,0)' : '',
264          opacity: o.opacity,
265          animation: useCssAnimations && addAnimation(o.opacity, o.trail, start + i * o.direction, o.lines) + ' ' + 1/o.speed + 's linear infinite'
266        })
267
268        if (o.shadow) ins(seg, css(fill('#000', '0 0 4px ' + '#000'), {top: 2+'px'}))
269        ins(el, ins(seg, fill(getColor(o.color, i), '0 0 1px rgba(0,0,0,.1)')))
270      }
271      return el
272    },
273
274    /**
275     * Internal method that adjusts the opacity of a single line.
276     * Will be overwritten in VML fallback mode below.
277     */
278    opacity: function(el, i, val) {
279      if (i < el.childNodes.length) el.childNodes[i].style.opacity = val
280    }
281
282  })
283
284
285  function initVML() {
286
287    /* Utility function to create a VML tag */
288    function vml(tag, attr) {
289      return createEl('<' + tag + ' xmlns="urn:schemas-microsoft.com:vml" class="spin-vml">', attr)
290    }
291
292    // No CSS transforms but VML support, add a CSS rule for VML elements:
293    sheet.addRule('.spin-vml', 'behavior:url(#default#VML)')
294
295    Spinner.prototype.lines = function(el, o) {
296      var r = o.length+o.width
297        , s = 2*r
298
299      function grp() {
300        return css(
301          vml('group', {
302            coordsize: s + ' ' + s,
303            coordorigin: -r + ' ' + -r
304          }),
305          { width: s, height: s }
306        )
307      }
308
309      var margin = -(o.width+o.length)*2 + 'px'
310        , g = css(grp(), {position: 'absolute', top: margin, left: margin})
311        , i
312
313      function seg(i, dx, filter) {
314        ins(g,
315          ins(css(grp(), {rotation: 360 / o.lines * i + 'deg', left: ~~dx}),
316            ins(css(vml('roundrect', {arcsize: o.corners}), {
317                width: r,
318                height: o.width,
319                left: o.radius,
320                top: -o.width>>1,
321                filter: filter
322              }),
323              vml('fill', {color: getColor(o.color, i), opacity: o.opacity}),
324              vml('stroke', {opacity: 0}) // transparent stroke to fix color bleeding upon opacity change
325            )
326          )
327        )
328      }
329
330      if (o.shadow)
331        for (i = 1; i <= o.lines; i++)
332          seg(i, -2, 'progid:DXImageTransform.Microsoft.Blur(pixelradius=2,makeshadow=1,shadowopacity=.3)')
333
334      for (i = 1; i <= o.lines; i++) seg(i)
335      return ins(el, g)
336    }
337
338    Spinner.prototype.opacity = function(el, i, val, o) {
339      var c = el.firstChild
340      o = o.shadow && o.lines || 0
341      if (c && i+o < c.childNodes.length) {
342        c = c.childNodes[i+o]; c = c && c.firstChild; c = c && c.firstChild
343        if (c) c.opacity = val
344      }
345    }
346  }
347
348  var probe = css(createEl('group'), {behavior: 'url(#default#VML)'})
349
350  if (!vendor(probe, 'transform') && probe.adj) initVML()
351  else useCssAnimations = vendor(probe, 'animation')
352
353  return Spinner
354
355}));
356