css3-transitions/Overview.src.html@a38c76f0336b
css3-transitions/Overview.src.html
Mon, 14 Jan 2013 16:26:52 -0800
- author
- Tab Atkins <jackalmage@gmail.com>
- date
- Mon, 14 Jan 2013 16:26:52 -0800
- changeset 7182
- a38c76f0336b
- parent 7174
- ab47414d690c
- child 7183
- 6013bb8b5fe9
- permissions
- -rw-r--r--
[css3-transitions] Fix outline-offset to transition as length.
1 <!DOCTYPE html PUBLIC '-//W3C//DTD HTML 4.01//EN'
2 'http://www.w3.org/TR/html4/strict.dtd'>
4 <html lang="en">
5 <head>
6 <title>CSS Transitions</title>
7 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
8 <link rel="stylesheet" type="text/css" href="../default.css">
9 <style type="text/css">
10 table.animatable-properties {
11 border-collapse: collapse;
12 }
13 table.animatable-properties td {
14 padding: 0.2em 1em;
15 border: 1px solid black;
16 }
17 div.prod { margin: 1em 2em; }
18 </style>
19 <link rel="stylesheet" type="text/css" href="http://www.w3.org/StyleSheets/TR/W3C-ED.css">
20 </head>
22 <body>
24 <div class="head">
25 <!--logo-->
27 <h1>CSS Transitions</h1>
29 <h2 class="no-num no-toc">[LONGSTATUS] [DATE]</h2>
30 <dl>
31 <dt>This version:
32 <dd>
33 <a href="[VERSION]">
34 http://dev.w3.org/csswg/css3-transitions/</a>
35 <!--http://www.w3.org/TR/[YEAR]/WD-[SHORTNAME]-[CDATE]/-->
36 <dt>Latest version:
37 <dd><a href="http://www.w3.org/TR/css3-transitions/">
38 [LATEST]</a>
39 <dt>Editor's draft:
40 <dd><a href="http://dev.w3.org/csswg/[SHORTNAME]/">http://dev.w3.org/csswg/[SHORTNAME]/</a>
41 <dt>Previous version:
42 <dd><a href="http://www.w3.org/TR/2012/WD-css3-transitions-20120403/">
43 http://www.w3.org/TR/2012/WD-css3-transitions-20120403/</a>
44 <dt id="editors-list">Editors:
45 <dd><a href="mailto:dino@apple.com">Dean Jackson</a> (<a
46 href="http://www.apple.com/">Apple Inc</a>)
47 <dd><a href="mailto:hyatt@apple.com">David Hyatt</a> (<a
48 href="http://www.apple.com/">Apple Inc</a>)
49 <dd><a href="mailto:cmarrin@apple.com">Chris Marrin</a> (<a
50 href="http://www.apple.com/">Apple Inc</a>)
51 <dd class=vcard><a class=fn href="http://dbaron.org/">L. David Baron</a> (<a
52 class=org href="http://www.mozilla.org/">Mozilla</a>)
54 <dt>Issues list:
55 <dd><a href="https://www.w3.org/Bugs/Public/buglist.cgi?query_format=advanced&product=CSS&component=Transitions&resolution=---&cmdtype=doit">in Bugzilla</a>
57 <dt>Discussion:</dt>
58 <dd><a href="http://lists.w3.org/Archives/Public/www-style/">www-style@w3.org</a> with subject line “<kbd>[[SHORTNAME]] <var>… message topic …</var></kbd>”
60 <dt>Test suite:
61 <dd>none yet
62 </dl>
64 <!--copyright-->
66 <hr title="Separator for header">
67 </div>
69 <h2 class="no-num no-toc" id="abstract">Abstract</h2>
71 <p>CSS Transitions allows property changes in CSS values to occur smoothly
72 over a specified duration.
74 <h2 class="no-num no-toc" id="status">Status of this document</h2>
75 <!--status-->
77 <p>
78 The <a href="ChangeLog">list of changes made to this specification</a> is
79 available.
80 </p>
82 <h2 class="no-num no-toc" id="contents">Table of contents</h2>
83 <!--toc-->
86 <h2 id="introduction">Introduction</h2>
88 <p><em>This section is not normative.</em>
89 <p>
90 This document introduces new CSS features to enable <em>implicit transitions</em>, which describe how CSS properties can be made to change smoothly from one value to another over a given duration.
91 </p>
93 <h2 id="transitions"><a id="transitions-">Transitions</a></h2>
94 <p>
95 Normally when the value of a CSS property changes, the rendered result is instantly updated, with the affected elements immediately changing from the old property value to the new property value. This section describes a way to specify transitions using new CSS properties. These properties are used to animate smoothly from the old state to the new state over time.
96 </p>
97 <p>
98 For example, suppose that transitions of one second have been defined on the <code class="property">'left'</code> and
99 <code class="property">'background-color'</code> properties. The following diagram illustrates the effect of updating those properties on an element, in this case moving it to the right and changing the background from red to blue. This assumes other transition parameters still have their default values.
100 </p>
101 <div class="figure">
102 <img src="transition1.png" alt="">
103 </div>
104 <p class="caption">
105 Transitions of <code class="property">'left'</code> and <code class="property">'background-color'</code>
106 </p>
107 <p>
108 Transitions are a presentational effect. The computed value of a property transitions over time from the old value to the new value. Therefore if a script queries the computed style of a property as it is transitioning, it will see an intermediate value that represents the current animated value of the property.
109 </p>
110 <p>
111 Only animatable CSS properties can be transitioned. See the table at the end of this document for a list
112 of properties that are animatable.
113 </p>
114 <p>
115 The transition for a property is defined using a number of new properties. For example:
116 </p>
117 <div class="example">
118 <p style="display:none">
119 Example(s):
120 </p>
121 <pre>
122 div {
123 transition-property: opacity;
124 transition-duration: 2s;
125 }
126 </pre>The above example defines a transition on the <code class="property">'opacity'</code> property that, when a new value is assigned to it, will cause a smooth change between the old value and the new value over a period of two seconds.
127 </div>
128 <p>
129 Each of the transition properties accepts a comma-separated list, allowing multiple transitions to be defined, each acting on a different property. In this case, the individual transitions take their parameters from the same index in all the lists. For example:
130 </p>
131 <div class="example">
132 <p style="display:none">
133 Example(s):
134 </p>
135 <pre>
136 div {
137 transition-property: opacity, left;
138 transition-duration: 2s, 4s;
139 }
141 </pre>This will cause the <code class="property">'opacity'</code> property to transition over a period of two seconds and the left property to transition over a period of four seconds.
142 </div>
144 <p id="list-matching">
145 In the case where the lists of values in transition properties
146 do not have the same length, the length of the
147 'transition-property' list determines the number of items in
148 each list examined when starting transitions. The lists are
149 matched up from the first value: excess values at the end are
150 not used. If one of the other properties doesn't have enough
151 comma-separated values to match the number of values of
152 'transition-property', the UA must calculate its used value by
153 repeating the list of values until there are enough. This
154 truncation or repetition does not affect the computed value.
155 <span class="note">
156 Note: This is analogous to the behavior of the 'background-*'
157 properties, with 'background-image' analogous to
158 'transition-property'.
159 </span>
160 </p>
162 <div class="example">
163 <p style="display:none">
164 Example(s):
165 </p>
166 <pre>
167 div {
168 transition-property: opacity, left, top, width;
169 transition-duration: 2s, 1s;
170 }
171 </pre>The above example defines a transition on the <code class="property">'opacity'</code> property of 2 seconds duration, a
172 transition on the <code class="property">'left'</code> property of 1
173 second duration, a transition on the <code class="property">'top'</code> property of 2 seconds duration and a
174 transition on the <code class="property">'width'</code> property of 1
175 second duration.
177 </div>
179 <!-- ======================================================================================================= -->
180 <h3 id=transition-property-property><a id=the-transition-property-property->
181 The <code class="property">'transition-property'</code> Property
182 </a></h3>
183 <p>
184 The <code class="property">'transition-property'</code> property specifies the name of the CSS property to which the transition is applied.
185 </p>
186 <div class="issue">
187 We may ultimately want to support a keypath syntax for this property. A keypath syntax would enable different transitions to be specified for components of a property. For example the blur of a shadow could have a different transition than the color of a shadow.
188 </div>
189 <table class="propdef">
190 <tbody>
191 <tr>
192 <td>
193 <em>Name:</em>
194 </td>
195 <td>
196 <dfn id="transition-property">transition-property</dfn>
197 </td>
198 </tr>
199 <tr>
200 <td>
201 <em>Value:</em>
202 </td>
203 <td>
204 none | <span><single-transition-property></span> [ ',' <span><single-transition-property></span> ]*
205 </td>
206 </tr>
207 <tr>
208 <td>
209 <em>Initial:</em>
210 </td>
211 <td>
212 all
213 </td>
214 </tr>
215 <tr>
216 <td>
217 <em>Applies to:</em>
218 </td>
219 <td>
220 all elements, :before and :after pseudo elements
221 </td>
222 </tr>
223 <tr>
224 <td>
225 <em>Inherited:</em>
226 </td>
227 <td>
228 no
229 </td>
230 </tr>
231 <tr>
232 <td>
233 <em>Animatable:</em>
234 </td>
235 <td>
236 no
237 </td>
238 </tr>
239 <tr>
240 <td>
241 <em>Percentages:</em>
242 </td>
243 <td>
244 N/A
245 </td>
246 </tr>
247 <tr>
248 <td>
249 <em>Media:</em>
250 </td>
251 <td>
252 visual
253 </td>
254 </tr>
255 <tr>
256 <td>
257 <em>Computed value:</em>
258 </td>
259 <td>
260 Same as specified value.
261 </td>
262 </tr>
263 <tr>
264 <td>
265 <em>Canonical order:</em>
266 </td>
267 <td>
268 <abbr title="follows order of property value definition">per grammar</abbr>
269 </td>
270 </tr>
271 </tbody>
272 </table>
274 <div class="prod">
275 <dfn id="single-transition-property"><single-transition-property></dfn> = all | <IDENT>
276 </div>
278 <p>
279 A value of 'none' means that no property will transition.
280 Otherwise, a list of properties to be transitioned, or the
281 keyword 'all' which indicates that all properties are to be
282 transitioned, is given.
283 </p>
285 <p>
286 If one of the identifiers listed is not a recognized property
287 name or is not an animatable property, the implementation must
288 still start transitions on the animatable properties in the
289 list using the duration, delay, and timing function at their
290 respective indices in the lists for 'transition-duration',
291 'transition-delay', and 'transition-timing-function'. In other
292 words, unrecognized or non-animatable properties must be kept in
293 the list to preserve the matching of indices.
294 </p>
295 <p class="issue">
296 Are 'none', 'inherit', and 'initial' allowed as items in
297 a list of identifiers (of length greater than one)?
298 </p>
299 <p>
300 For the keyword 'all', or if one of the identifiers listed is a
301 shorthand property, implementations must start transitions for
302 any of its longhand sub-properties that are animatable (or, for
303 'all', all animatable properties), using the duration, delay,
304 and timing function at the index corresponding to the shorthand.
305 </p>
306 <p>
307 If a property is specified multiple times in the value of
308 'transition-property' (either on its own, via a shorthand that
309 contains it, or via the 'all' value), then the transition that
310 starts uses the duration, delay, and timing function at the
311 index corresponding to the <em>last</em> item in the value of
312 'transition-property' that calls for animating that property.
313 </p>
314 <p class="note">
315 Note: The <code class="property">all</code> value and shorthand
316 properties work in similar ways, so the <code
317 class="property">all</code> value is just like a shorthand that
318 covers all properties.
319 </p>
321 <!-- ======================================================================================================= -->
322 <h3 id=transition-duration-property><a id=the-transition-duration-property->
323 The <code class="property">'transition-duration'</code> Property
324 </a></h3>
325 <p>
326 The <code class="property">'transition-duration'</code> property defines the length of time that a transition takes.
327 </p>
328 <table class="propdef">
329 <tbody>
330 <tr>
331 <td>
332 <em>Name:</em>
333 </td>
334 <td>
335 <dfn id="transition-duration">transition-duration</dfn>
336 </td>
337 </tr>
338 <tr>
339 <td>
340 <em>Value:</em>
341 </td>
342 <td>
343 <span><time></span> [, <span><time></span>]*
344 </td>
345 </tr>
346 <tr>
347 <td>
348 <em>Initial:</em>
349 </td>
350 <td>
351 0s
352 </td>
353 </tr>
354 <tr>
355 <td>
356 <em>Applies to:</em>
357 </td>
358 <td>
359 all elements, :before and :after pseudo elements
360 </td>
361 </tr>
362 <tr>
363 <td>
364 <em>Inherited:</em>
365 </td>
366 <td>
367 no
368 </td>
369 </tr>
370 <tr>
371 <td>
372 <em>Animatable:</em>
373 </td>
374 <td>
375 no
376 </td>
377 </tr>
378 <tr>
379 <td>
380 <em>Percentages:</em>
381 </td>
382 <td>
383 N/A
384 </td>
385 </tr>
386 <tr>
387 <td>
388 <em>Media:</em>
389 </td>
390 <td>
391 interactive
392 </td>
393 </tr>
394 <tr>
395 <td>
396 <em>Computed value:</em>
397 </td>
398 <td>
399 Same as specified value.
400 </td>
401 </tr>
402 <tr>
403 <td>
404 <em>Canonical order:</em>
405 </td>
406 <td>
407 <abbr title="follows order of property value definition">per grammar</abbr>
408 </td>
409 </tr>
410 </tbody>
411 </table>
412 <p>
413 This property specifies how long the transition from the old value to the new value should take. By default the value is '0s', meaning that the transition is immediate (i.e. there will be no animation). A negative value for <code class="property">transition-duration</code> renders the declaration invalid.
414 </p>
416 <!-- =======================================================================================================
417 -->
419 <h3 id=transition-timing-function-property><a id=transition-timing-function_tag>
420 The <code class="property">'transition-timing-function'</code> Property
421 </a></h3>
422 <p>
423 The <code class="property">'transition-timing-function'</code> property
424 describes how the intermediate values used during a transition will be
425 calculated. It allows for a transition to change speed over its
426 duration. These effects are commonly called <em>easing</em> functions.
427 In either case, a mathematical function that provides a smooth curve is
428 used.
429 </p>
430 <p>
431 Timing functions are either defined as a stepping function or
432 a <a
433 href="http://en.wikipedia.org/wiki/B%C3%A9zier_curve#Cubic_B.C3.A9zier_curves">cubic
434 Bézier curve</a>.
435 The timing function takes as its input
436 the current elapsed percentage of the transition duration
437 and outputs the percentage of the way the transition is
438 from its start value to its end value.
439 How this output is used is defined by
440 the <a href="#animatable-types">interpolation rules</a>
441 for the value type.
442 </p>
443 <p>
444 A <a href="http://en.wikipedia.org/wiki/Step_function">stepping</a>
445 function is defined by a number that divides the domain of operation
446 into equally sized intervals. Each subsequent interval is a equal step
447 closer to the goal state. The function also specifies whether the
448 change in output percentage happens at the start or end of the
449 interval (in other words, if 0% on the input percentage is the point
450 of initial change).
451 </p>
452 <div class="figure">
453 <img src="step.png" alt="The step timing function splits
454 the function domain into a number of disjoint straight line
455 segments. steps(1, start) is a function whose
456 output value is 1 for all input values. steps(1, end) is a function whose
457 output value is 0 for all input values less than 1, and output
458 is 1 for the input value of 1. steps(3, start) is a function that
459 divides the input domain into three segments, each 1/3 in length,
460 and 1/3 above the previous segment, with the first segment starting
461 at 1/3. steps(3, end) is a function that
462 divides the input domain into three segments, each 1/3 in length,
463 and 1/3 above the previous segment, with the first segment starting
464 at 0.">
465 </div>
466 <p class="caption">
467 Step timing functions
468 </p>
469 <p>
470 A <a
471 href="http://en.wikipedia.org/wiki/B%C3%A9zier_curve#Cubic_B.C3.A9zier_curves">cubic
472 Bézier curve</a> is defined by four control points, P<sub>0</sub>
473 through P<sub>3</sub> (see Figure 1). P<sub>0</sub> and P<sub>3</sub>
474 are always set to (0,0) and (1,1). The <code class="property">'transition-timing-function'</code> property is used
475 to specify the values for points P<sub>1</sub> and P<sub>2</sub>. These
476 can be set to preset values using the keywords listed below, or can be
477 set to specific values using the <code class="css">'cubic-bezier'</code> function.
478 In the <code class="css">'cubic-bezier'</code> function, P<sub>1</sub> and
479 P<sub>2</sub> are each specified by both an X and Y value.
480 </p>
481 <div class="figure">
482 <img src="TimingFunction.png" alt="The Bézier timing function is a
483 smooth curve from point P0 = (0,0) to point P3 = (1,1). The
484 length and orientation of the line segment P0-P1 determines
485 the tangent and the curvature of the curve at P0 and the
486 line segment P2-P3 does the same at P3.">
487 </div>
488 <p class="caption">
489 Bézier Timing Function Control Points
490 </p>
491 <table class="propdef">
492 <tbody>
493 <tr>
494 <td>
495 <em>Name:</em>
496 </td>
497 <td>
498 <dfn id="transition-timing-function">transition-timing-function</dfn>
499 </td>
500 </tr>
501 <tr>
502 <td>
503 <em>Value:</em>
504 </td>
505 <td>
506 <span><single-transition-timing-function></span> [ ',' <span><single-transition-timing-function></span> ]*
507 </td>
508 </tr>
509 <tr>
510 <td>
511 <em>Initial:</em>
512 </td>
513 <td>
514 ease
515 </td>
516 </tr>
517 <tr>
518 <td>
519 <em>Applies to:</em>
520 </td>
521 <td>
522 all elements, :before and :after pseudo elements
523 </td>
524 </tr>
525 <tr>
526 <td>
527 <em>Inherited:</em>
528 </td>
529 <td>
530 no
531 </td>
532 </tr>
533 <tr>
534 <td>
535 <em>Animatable:</em>
536 </td>
537 <td>
538 no
539 </td>
540 </tr>
541 <tr>
542 <td>
543 <em>Percentages:</em>
544 </td>
545 <td>
546 N/A
547 </td>
548 </tr>
549 <tr>
550 <td>
551 <em>Media:</em>
552 </td>
553 <td>
554 interactive
555 </td>
556 </tr>
557 <tr>
558 <td>
559 <em>Computed value:</em>
560 </td>
561 <td>
562 Same as specified value.
563 </td>
564 </tr>
565 <tr>
566 <td>
567 <em>Canonical order:</em>
568 </td>
569 <td>
570 <abbr title="follows order of property value definition">per grammar</abbr>
571 </td>
572 </tr>
573 </tbody>
574 </table>
575 <div class="prod">
576 <dfn id="single-transition-timing-function"><single-transition-timing-function></dfn> = ease | linear | ease-in | ease-out | ease-in-out | step-start | step-end | steps(<integer>[, [ start | end ] ]?) | cubic-bezier(<number>, <number>, <number>, <number>)
577 </div>
578 <p>
579 The timing functions have the following definitions.
580 </p>
581 <dl>
582 <dt>
583 ease
584 </dt>
585 <dd>
586 The ease function is equivalent to cubic-bezier(0.25, 0.1, 0.25, 1).
587 </dd>
588 <dt>
589 linear
590 </dt>
591 <dd>
592 The linear function is equivalent to cubic-bezier(0, 0, 1, 1).
593 </dd>
594 <dt>
595 ease-in
596 </dt>
597 <dd>
598 The ease-in function is equivalent to cubic-bezier(0.42, 0, 1, 1).
599 </dd>
600 <dt>
601 ease-out
602 </dt>
603 <dd>
604 The ease-out function is equivalent to cubic-bezier(0, 0, 0.58, 1).
605 </dd>
606 <dt>
607 ease-in-out
608 </dt>
609 <dd>
610 The ease-in-out function is equivalent to cubic-bezier(0.42, 0, 0.58, 1)
611 </dd>
612 <dt>
613 step-start
614 </dt>
615 <dd>
616 The step-start function is equivalent to steps(1, start).
617 </dd>
618 <dt>
619 step-end
620 </dt>
621 <dd>
622 The step-end function is equivalent to steps(1, end).
623 </dd>
624 <dt>
625 steps(<integer>[, [ start | end ] ]?)
626 </dt>
627 <dd>
628 Specifies a stepping function, described above, taking two
629 parameters. The first parameter specifies the number of intervals
630 in the function. It must be a positive integer (greater than 0).
631 The second parameter, which is optional, is
632 either the value 'start' or 'end', and specifies the point
633 at which the change of values occur within the interval.
634 If the second parameter is omitted, it is given the value 'end'.
635 </dd>
636 <dt>
637 cubic-bezier(<number>, <number>, <number>, <number>)
638 </dt>
639 <dd>
640 Specifies a <a
641 href="http://en.wikipedia.org/wiki/B%C3%A9zier_curve">cubic-bezier
642 curve</a>. The four values specify points P<sub>1</sub> and
643 P<sub>2</sub> of the curve as (x1, y1, x2, y2). Both x values must be
644 in the range [0, 1] or the definition is invalid. The y values can
645 exceed this range.
646 </dd>
647 </dl><!-- ======================================================================================================= -->
648 <h3 id=transition-delay-property><a id=the-transition-delay-property->
649 The <code class="property">'transition-delay'</code> Property
650 </a></h3>
651 <p>
652 The <code class="property">'transition-delay'</code> property defines when the transition will start. It allows a transition to begin execution some some period of time from when it is applied. A <code class="property">'transition-delay'</code> value of '0s' means the transition will execute as soon as the property is changed. Otherwise, the value specifies an offset from the moment the property is changed, and the transition will delay execution by that offset.
653 </p>
654 <p>
655 If the value for <code class="property">'transition-delay'</code> is a negative time offset then the transition will execute the moment the property is changed, but will appear to have begun execution at the specified offset. That is, the transition will appear to begin part-way through its play cycle. In the case where a transition has implied starting values and a negative <code class="property">'transition-delay'</code>, the starting values are taken from the moment the property is changed.
656 </p>
657 <table class="propdef">
658 <tbody>
659 <tr>
660 <td>
661 <em>Name:</em>
662 </td>
663 <td>
664 <dfn id="transition-delay">transition-delay</dfn>
665 </td>
666 </tr>
667 <tr>
668 <td>
669 <em>Value:</em>
670 </td>
671 <td>
672 <span><time></span> [, <span><time></span>]*
673 </td>
674 </tr>
675 <tr>
676 <td>
677 <em>Initial:</em>
678 </td>
679 <td>
680 0s
681 </td>
682 </tr>
683 <tr>
684 <td>
685 <em>Applies to:</em>
686 </td>
687 <td>
688 all elements, :before and :after pseudo elements
689 </td>
690 </tr>
691 <tr>
692 <td>
693 <em>Inherited:</em>
694 </td>
695 <td>
696 no
697 </td>
698 </tr>
699 <tr>
700 <td>
701 <em>Animatable:</em>
702 </td>
703 <td>
704 no
705 </td>
706 </tr>
707 <tr>
708 <td>
709 <em>Percentages:</em>
710 </td>
711 <td>
712 N/A
713 </td>
714 </tr>
715 <tr>
716 <td>
717 <em>Media:</em>
718 </td>
719 <td>
720 interactive
721 </td>
722 </tr>
723 <tr>
724 <td>
725 <em>Computed value:</em>
726 </td>
727 <td>
728 Same as specified value.
729 </td>
730 </tr>
731 <tr>
732 <td>
733 <em>Canonical order:</em>
734 </td>
735 <td>
736 <abbr title="follows order of property value definition">per grammar</abbr>
737 </td>
738 </tr>
739 </tbody>
740 </table><!-- ======================================================================================================= -->
741 <h3 id=transition-shorthand-property><a id=the-transition-shorthand-property->
742 The <code class="property">'transition'</code> Shorthand Property
743 </a></h3>
744 <p>
745 The <code class="property">'transition'</code> shorthand property combines the four properties described above into a single property.
746 </p>
747 <table class="propdef">
748 <tbody>
749 <tr>
750 <td>
751 <em>Name:</em>
752 </td>
753 <td>
754 <dfn id="transition">transition</dfn>
755 </td>
756 </tr>
757 <tr>
758 <td>
759 <em>Value:</em>
760 </td>
761 <td>
762 <span><single-transition></span> [ ',' <span><single-transition></span> ]*
763 </td>
764 </tr>
765 <tr>
766 <td>
767 <em>Initial:</em>
768 </td>
769 <td>
770 see individual properties
771 </td>
772 </tr>
773 <tr>
774 <td>
775 <em>Applies to:</em>
776 </td>
777 <td>
778 all elements, :before and :after pseudo elements
779 </td>
780 </tr>
781 <tr>
782 <td>
783 <em>Inherited:</em>
784 </td>
785 <td>
786 no
787 </td>
788 </tr>
789 <tr>
790 <td>
791 <em>Animatable:</em>
792 </td>
793 <td>
794 no
795 </td>
796 </tr>
797 <tr>
798 <td>
799 <em>Percentages:</em>
800 </td>
801 <td>
802 N/A
803 </td>
804 </tr>
805 <tr>
806 <td>
807 <em>Media:</em>
808 </td>
809 <td>
810 interactive
811 </td>
812 </tr>
813 <tr>
814 <td>
815 <em>Computed value:</em>
816 </td>
817 <td>
818 Same as specified value.
819 </td>
820 </tr>
821 <tr>
822 <td>
823 <em>Canonical order:</em>
824 </td>
825 <td>
826 <abbr title="follows order of property value definition">per grammar</abbr>
827 </td>
828 </tr>
829 </tbody>
830 </table>
832 <div class="prod">
833 <dfn id="single-transition"><single-transition></dfn> = [ none | <span><single-transition-property></span> ] || <span><time></span> || <span><single-transition-timing-function></span> || <span><time></span>
834 </div>
836 <p>
837 Note that order is important within the items in this property:
838 the first value that can be parsed as a time is assigned to the
839 transition-duration,
840 and the second value that can be parsed as a time is assigned to
841 transition-delay.
842 </p>
844 <p class="issue">
845 An alternative proposal is to accept the font shorthand approach of
846 using a "/" character between the values of the same type. e.g. 2s/4s would
847 mean a duration of 2 seconds and a delay of 4 seconds.
848 </p>
850 <p>
851 If there is more than one <span><single-transition></span> in the shorthand,
852 and any of the transitions has
853 ''none'' as the <span><single-transition-property></span>,
854 then the declaration is invalid.
855 </p>
857 <h2 id="starting">
858 Starting of transitions
859 </h2>
861 <p>
862 When the computed value of an animatable property changes,
863 implementations must decide what transitions to start based on
864 the values of the 'transition-property', 'transition-duration',
865 'transition-timing-function', and 'transition-delay' properties
866 at the time the animatable property would first have its new
867 computed value.
868 </p>
869 <div class="example" id="manual-reversing-example">
870 <p style="display:none">
871 Example(s):
872 </p>
873 <p>This provides a way for authors to specify different values
874 of the 'transition-*' properties for the “forward”
875 and “reverse” transitions (but see <a
876 href="#reversing">below</a> for special reversing behavior when
877 an <em>incomplete</em> transition is interrupted). Authors can
878 specify the value of 'transition-duration',
879 'transition-timing-function', or 'transition-delay' in the same
880 rule where they specify the value that triggers the transition,
881 or can change these properties at the same time as they change
882 the property that triggers the transition. Since it's the new
883 values of these 'transition-*' properties that affect the
884 transition, these values will be used for the transitions
885 <em>to</em> the associated transitioning values. For example:
886 </p>
887 <pre>li {
888 transition: background-color linear 1s;
889 background: blue;
890 }
891 li:hover {
892 background-color: green;
893 transition-duration: 2s; /* applies to the transition *to* the :hover state */
894 }</pre>
895 <p>
896 When a list item with these style rules enters the :hover
897 state, the computed 'transition-duration' at the time that
898 'background-color' would have its new value ('green') is '2s',
899 so the transition from 'blue' to 'green' takes 2 seconds.
900 However, when the list item leaves the :hover state, the
901 transition from 'green' to 'blue' takes 1 second.
902 </p>
903 </div>
905 <p>
906 When the computed value of a property changes, implementations
907 must start transitions based on the relevant item (see <a
908 href="#transition-property">the definition of
909 'transition-property'</a>) in the computed value of
910 'transition-property'.
911 Corresponding to this item there are
912 computed values of 'transition-duration' and 'transition-delay'
913 (see <a href="#list-matching">the rules on matching lists</a>).
914 Define the <dfn>combined duration</dfn> of the transition
915 as the sum of max('transition-duration', '0s') and 'transition-delay'.
916 When the combined duration is greater than '0s',
917 then a transition starts based on the values of
918 'transition-duration', 'transition-delay',
919 and 'transition-timing-function';
920 in other cases transitions do not occur.
921 </p>
923 <p>
924 Since this specification does not define
925 when computed values change, and thus what changes to
926 computed values are considered simultaneous,
927 authors should be aware that changing any of the transition
928 properties a small amount of time after making a change that
929 might transition can result in behavior that varies between
930 implementations, since the changes might be considered
931 simultaneous in some implementations but not others.
932 </p>
933 <p class="note">Say something about simultaneity</p>
935 <p>
936 Once the transition of a property has started, it must continue
937 running based on the original timing function, duration, and
938 delay, even if the 'transition-timing-function',
939 'transition-duration', or 'transition-delay' property changes
940 before the transition is complete. However, if the
941 'transition-property' property changes such that the transition
942 would not have started, the transition must stop (and the
943 property must immediately change to its final value).
944 </p>
946 <p>
947 Implementations must not start a transition when the computed
948 value of a property changes as a result of declarative animation
949 (as opposed to scripted animation).
950 </p>
952 <p>
953 Implementations also must not start a transition when the
954 computed value changes because it is inherited (directly or
955 indirectly) from another element that is transitioning the same
956 property.
957 </p>
959 <h2 id="reversing">
960 Automatically reversing interrupted transitions
961 </h2>
962 <p>
963 A common type of transition effect is when a running transition is
964 interrupted and the property is reset to its original value. An
965 example is a hover effect on an element, where the pointer enters and
966 exits the element before the effect has completed. If the outgoing and
967 incoming transitions are executed using their specified durations and
968 timing functions, the resulting effect can be distractingly
969 asymmetric. Instead, the expected behavior is that the new transition
970 should be the reverse of what has already executed.
971 </p>
973 <p>
974 If a running transition with duration T, executing so far for duration TE,
975 from state A, to state B, is interrupted by
976 a property change that would start a new transition back to state A, and
977 all the transition attributes are the same (duration, delay and timing function),
978 then the new transition must reverse the effect. The new transition must:
979 </p>
981 <ol>
982 <li>
983 Use the B and A states as its "from" and "to" states respectively. It
984 does not use the current value as its from state, due to the rules below.
985 </li>
986 <li>
987 Execute with the same duration T, but starting as if the transition had
988 already begun, without any transition delay, at the moment which would
989 cause the new transition to finish in TE from the moment of interruption. In other
990 words, the new transition will execute as if it started T-TE in the past.
991 </li>
992 <li>
993 Use a timing function that is the portion of the curve traversed up
994 to the moment of interruption, followed in the opposite direction (towards
995 the starting point). This will make the transition appear as if it
996 is playing backwards.
997 </li>
998 <li>
999 Ignore any transition delay.
1000 </li>
1001 </ol>
1003 <p>
1004 For example, suppose there is a transition with a duration of two
1005 seconds. If this transition is interrupted after 0.5 seconds and the
1006 property value assigned to the original value, then the new transition
1007 effect will be the reverse of the original, as if it had begun
1008 1.5 seconds in the past.
1009 </p>
1011 <p>
1012 Note that by using the defined from and to states for the reversing
1013 transition, it is also possible that it may reverse again, if
1014 interrupted; for example, if the transition reversing to state A was
1015 again interrupted by a property change to state B.
1016 </p>
1018 <p class="issue">Issue:
1019 This introduces the concept of reversing a timing function,
1020 which the spec has otherwise resisted doing, and also introduces
1021 a discontinuity between transitions that have
1022 almost completed (which get automatically reversed and thus have
1023 their timing function reversed) and transitions that have fully
1024 completed (where the reversal doesn't lead to the timing
1025 function being reversed). An alternative proposal that avoids
1026 this is to follow the normal timing function algorithm, except
1027 multiply the duration (and also shorten any negative delay) by
1028 the (output) value of the transition timing function of the
1029 incomplete transition at the time it was interrupted, and, to
1030 account for multiple reverses in sequence, to divide by the
1031 shortening applied to the transition being interrupted. For
1032 more details see this thread:
1033 <a href="http://lists.w3.org/Archives/Public/www-style/2009Nov/thread.html#msg302">November 2009 part</a>,
1034 <a href="http://lists.w3.org/Archives/Public/www-style/2009Dec/thread.html#msg319">December 2009 part</a>,
1035 <a href="http://lists.w3.org/Archives/Public/www-style/2010Jan/thread.html#msg136">January 2010 part</a>.
1036 </p>
1038 <h2 id=transition-events><a id=transition-events->
1039 Transition Events
1040 </a></h2>
1041 <p>
1042 The completion of a CSS Transition generates a corresponding <a href="http://www.w3.org/TR/DOM-Level-2-Events/events.html">DOM Event</a>.
1043 An event is fired for each property that undergoes a transition.
1044 This allows a content developer to perform actions that synchronize
1045 with the completion of a transition.
1046 </p>
1047 <p>
1048 Each event provides the name of the property the transition is
1049 associated with as well as the duration of the transition.
1050 </p>
1051 <dl>
1052 <dt>
1053 <b>Interface <i><a id="Events-TransitionEvent" name='Events-TransitionEvent'>TransitionEvent</a></i></b>
1054 </dt>
1055 <dd>
1056 <p>
1057 The <code>TransitionEvent</code> interface provides specific contextual information associated with transitions.
1058 </p>
1059 <dl>
1060 <dt>
1061 <b>IDL Definition</b>
1062 </dt>
1063 <dd>
1064 <div class='idl-code'>
1065 <pre>
1066 interface TransitionEvent : Event {
1067 readonly attribute DOMString propertyName;
1068 readonly attribute float elapsedTime;
1069 readonly attribute DOMString pseudoElement;
1070 void initTransitionEvent(in DOMString typeArg,
1071 in boolean canBubbleArg,
1072 in boolean cancelableArg,
1073 in DOMString propertyNameArg,
1074 in float elapsedTimeArg,
1075 in DOMString pseudoElementArg);
1076 };
1077 </pre>
1078 </div>
1079 </dd>
1080 <dt>
1081 <b>Attributes</b>
1082 </dt>
1083 <dd>
1084 <dl>
1085 <dt>
1086 <code class='attribute-name'><a id="Events-TransitionEvent-propertyName" name='Events-TransitionEvent-propertyName'>propertyName</a></code> of type <code>DOMString</code>, readonly
1087 </dt>
1088 <dd>
1089 The name of the CSS property associated with the transition.
1090 </dd>
1091 </dl>
1092 <dl>
1093 <dt>
1094 <code class='attribute-name'><a id="Events-TransitionEvent-elapsedTime" name='Events-TransitionEvent-elapsedTime'>elapsedTime</a></code> of type <code>float</code>, readonly
1095 </dt>
1096 <dd>
1097 The amount of time the transition has been running, in seconds, when this event fired. Note that this value is not affected by the value of <code class="property">transition-delay</code>.
1098 </dd>
1099 </dl>
1100 <dl>
1101 <dt>
1102 <code class='attribute-name'><a id="Events-TransitionEvent-pseudoElement" name='Events-TransitionEvent-pseudoElement'>pseudoElement</a></code> of type <code>DOMString</code>, readonly
1103 </dt>
1104 <dd>
1105 The name (beginning with two colons) of the CSS
1106 pseudo-element on which the transition occured (in
1107 which case the target of the event is that
1108 pseudo-element's corresponding element), or the empty
1109 string if the transition occurred on an element (which
1110 means the target of the event is that element).
1111 </dd>
1112 </dl>
1113 </dd>
1114 <dt>
1115 <b>Methods</b>
1116 </dt>
1117 <dd>
1118 <dl>
1119 <dt>
1120 <code class='method-name'><a id="Events-TransitionEvent-initTransitionEvent" name='Events-TransitionEvent-initTransitionEvent'>initTransitionEvent</a></code>
1121 </dt>
1122 <dd>
1123 <div class='method'>
1124 The <code>initTransitionEvent</code> method is used to
1125 initialize the value of a <code>TransitionEvent</code>
1126 created through the <a
1127 href='http://www.w3.org/TR/DOM-Level-2-Events/events.html#Events-DocumentEvent'><code>DocumentEvent</code></a>
1128 interface. This method may only be called before the
1129 <code>TransitionEvent</code> has been dispatched via the
1130 <code>dispatchEvent</code> method, though it may be called
1131 multiple times during that phase if necessary. If called
1132 multiple times, the final invocation takes precedence.
1133 <p class="issue">Should new events being created still
1134 have init*Event methods?</p>
1135 <div class='parameters'>
1136 <b>Parameters</b>
1137 <div class='paramtable'>
1138 <dl>
1139 <dt>
1140 <code class='parameter-name'>typeArg</code> of type <code>DOMString</code>
1141 </dt>
1142 <dd>
1143 Specifies the event type.<br>
1144 </dd>
1145 <dt>
1146 <code class='parameter-name'>canBubbleArg</code> of type <code>boolean</code>
1147 </dt>
1148 <dd>
1149 Specifies whether or not the event can bubble.<br>
1150 </dd>
1151 <dt>
1152 <code class='parameter-name'>cancelableArg</code> of type <code>boolean</code>
1153 </dt>
1154 <dd>
1155 Specifies whether or not the event's default action can be prevented. Since a TransitionEvent
1156 is purely for notification, there is no default action.<br>
1157 </dd>
1158 <dt>
1159 <code class='parameter-name'>propertyNameArg</code> of type <code>DOMString</code>
1160 </dt>
1161 <dd>
1162 Specifies the name of the property associated with the <a href='http://www.w3.org/TR/DOM-Level-2-Events/events.html#Events-Event'><code>Event</code></a>.
1163 (See the <a href="#Events-TransitionEvent-propertyName">propertyName</a> attribute.)
1164 </dd>
1165 <dt>
1166 <code class='parameter-name'>elapsedTimeArg</code> of type <code>float</code>
1167 </dt>
1168 <dd>
1169 Specifies the amount of time, in seconds, the transition has been running at the time of initialization.
1170 (See the <a href="#Events-TransitionEvent-elapsedTime">elapsedTime</a> attribute.)
1171 </dd>
1172 <dt>
1173 <code class='parameter-name'>pseudoElementArg</code> of type <code>DOMString</code>
1174 </dt>
1175 <dd>
1176 Specifies the pseudo-element on which the
1177 transition occurred.
1178 (See the <a href="#Events-TransitionEvent-pseudoElement">pseudoElement</a> attribute.)
1179 <span class="issue">Does adding this additional argument create any compatibility problems?</span>
1180 </dd>
1181 </dl>
1182 </div>
1183 </div><!-- parameters -->
1184 <div>
1185 <b>No Return Value</b>
1186 </div>
1187 <div>
1188 <b>No Exceptions</b>
1189 </div>
1190 </div><!-- method -->
1191 </dd>
1192 </dl>
1193 </dd>
1194 </dl>
1195 </dd>
1196 </dl>
1197 <p>
1198 There is one type of transition event available.
1199 </p>
1200 <dl>
1201 <dt>
1202 <b>transitionend</b>
1203 </dt>
1204 <dd>
1205 The 'transitionend' event occurs at the completion of the transition. In the
1206 case where a transition is removed before completion, such as if the
1207 transition-property is removed, then the event will not fire.
1208 <ul>
1209 <li>Bubbles: Yes
1210 </li>
1211 <li>Cancelable: Yes
1212 </li>
1213 <li>Context Info: propertyName, elapsedTime
1214 </li>
1215 </ul>
1216 </dd>
1217 </dl>
1219 <h2 id="animatable-types"><a id=animation-of-property-types->
1220 Animation of property types
1221 </a></h2>
1223 <p>
1224 When interpolating between two values,
1225 <i>V</i><sub>start</sub> and <i>V</i><sub>end</sub>,
1226 interpolation is done using the output <i>p</i> of the timing function,
1227 which gives the portion of the value space
1228 that the interpolation has crossed.
1229 Thus the result of the interpolation is
1230 <i>V</i><sub>res</sub> =
1231 (1 - <i>p</i>) ⋅ <i>V</i><sub>start</sub> +
1232 <i>p</i> ⋅ <i>V</i><sub>end</sub>.
1233 </p>
1235 <p>
1236 However, if this value (<i>V</i><sub>res</sub>)
1237 is outside the allowed range of values for the property,
1238 then it is clamped to that range.
1239 This can occur if <i>p</i> is outside of the range 0 to 1,
1240 which can occur if a timing function is specified
1241 with a <i>y1</i> or <i>y2</i> that is outside the range 0 to 1.
1242 </p>
1244 <p>
1245 The following describes how each property type undergoes transition or
1246 animation.
1247 </p>
1249 <ul>
1250 <li>
1251 <strong>color</strong>: interpolated via red, green, blue and alpha
1252 components (treating each as a number, see below).
1253 <div class="issue">Issue: Are the colors interpolated in
1254 premultiplied space or non-premultiplied space?</div>
1255 </li>
1256 <li>
1257 <strong>length</strong>: interpolated as real numbers.
1258 </li>
1259 <li>
1260 <strong>percentage</strong>: interpolated as real numbers.
1261 </li>
1262 <li>
1263 <strong>integer</strong>: interpolated via discrete steps (whole
1264 numbers). The interpolation happens in real number space and is
1265 converted to an integer using <code>floor()</code>.
1266 <span class="issue">
1267 This floor behavior is inconsistent with SMIL Animation /
1268 SVG Animation.
1269 </span>
1270 </li>
1271 <li>
1272 <strong>font weight</strong>: interpolated via discrete steps
1273 (multiples of 100). The interpolation happens in real number
1274 space and is converted to an integer by rounding to the
1275 nearest multiple of 100.
1276 <span class="issue">
1277 This round-to-nearest behavior is inconsistent with the
1278 floor behavior used for integer types, but probably should
1279 be consistent (one way or the other).
1280 </span>
1281 </li>
1282 <li>
1283 <strong>number</strong>: interpolated as real (floating point)
1284 numbers.
1285 </li>
1286 <li>
1287 <strong>transform list</strong>: see
1288 CSS Transforms specification [[!CSS3-TRANSFORMS]].
1289 </li>
1290 <li>
1291 <strong>rectangle</strong>: interpolated via the x, y,
1292 width and height components (treating each as a number).
1293 </li>
1294 <li>
1295 <strong>visibility</strong>: if one of the values is
1296 'visible', interpolated as a discrete step where values of the
1297 timing function between 0 and 1 map to 'visible' and other
1298 values of the timing function (which occur only at the
1299 start/end of the transition or as a result of 'cubic-bezier()'
1300 functions with Y values outside of [0, 1]) map to the closer
1301 endpoint; if neither value is 'visible' then not interpolable.
1302 </li>
1303 <li>
1304 <strong>shadow</strong>: interpolated via the color, x, y
1305 and blur components (treating them as color and numbers where
1306 appropriate). In the case where there are lists of shadows,
1307 the shorter list is padded at the end with shadows whose
1308 color is transparent and all lengths (x, y, blur) are 0.
1309 </li>
1310 <li>
1311 <strong>gradient</strong>: interpolated via the
1312 positions and colors of each stop. They must have the same type
1313 (radial or linear) and same number of stops in order to be animated.
1314 <span class="note">Note: [[CSS3-IMAGES]] may extend this
1315 definition.</span>
1316 </li>
1317 <li>
1318 <strong>paint server</strong> (SVG): interpolation is only supported
1319 between: gradient to gradient and color to color. They then
1320 work as above.
1321 </li>
1322 <li>
1323 <strong>list of above types</strong>: If the lists have the
1324 same number of items, each item in the list is interpolated using the
1325 rules above. Otherwise the interpolation is determined by the property
1326 rules. If the property extends its list by repeating values, then this
1327 repeated form will be used in the interpolation (<code class="property">'background-position'</code>
1328 is an example of a property that would transition between lists of different lengths). If
1329 the property does not allow extending its list, then no interpolation
1330 will occur.
1331 </li>
1332 <li>
1333 <strong>a shorthand property</strong>: If any part of a
1334 shorthand can be animated, then interpolation is performed as
1335 if those animatable properties were individually specified.
1336 </li>
1337 </ul>
1339 <p class="issue">Need to add a length-percentage-calc type.</p>
1341 <p>Future specifications may define additional types that can
1342 be animated.</p>
1344 <h2 id=animatable-properties><a id=animatable-properties->
1345 Animatable properties
1346 </a></h2>
1348 <!--
1349 As resolved in
1350 http://lists.w3.org/Archives/Public/www-style/2011Sep/0497.html
1351 -->
1352 <p>For properties that exist at the time this specification was
1353 developed, this specification defines whether and how they are
1354 animated. However, future CSS specifications may define
1355 additional properties, additional values for existing properties,
1356 or additional animation behavior of existing values. In order to
1357 describe new animation behaviors and to have the definition of
1358 animation behavior in a more appropriate location, future CSS
1359 specifications should include an "Animatable:" line in the summary
1360 of the property's definition (in addition to the other lines
1361 described in [[CSS21]], <a
1362 href="http://www.w3.org/TR/CSS21/about.html#property-defs">section
1363 1.4.2</a>). This line should say "no" to indicate that a property
1364 cannot be animated or should reference an animation behavior
1365 (which may be one of the behaviors in the <a
1366 href="#animation-of-property-types-">Animation of property
1367 types</a> section above, or may be a new behavior) to define how
1368 the property animates. Such definitions override those given in
1369 this specification.</p>
1371 <h3 id=animatable-css><a id=properties-from-css->
1372 Properties from CSS
1373 </a></h3>
1375 <p class="issue">Need to define what listing comma-separated
1376 things here means. In particular, that they only apply when
1377 both values fit the type, and that if one of the values is a
1378 type not listed, or if two of the values are different types,
1379 then the two values cannot be interpolated.</p>
1381 <table class="animatable-properties">
1382 <tr>
1383 <th>Property Name</th>
1384 <th>Type</th>
1385 </tr>
1386 <tr>
1387 <td>background-color</td><td>color</tr>
1388 <tr>
1389 <td>background-position</td><td>percentage, length</td>
1390 </tr>
1391 <tr>
1392 <td>border-bottom-color</td><td>color</td>
1393 </tr>
1394 <tr>
1395 <td>border-bottom-width</td><td>length</td>
1396 </tr>
1397 <tr>
1398 <td>border-left-color</td><td>color</td>
1399 </tr>
1400 <tr>
1401 <td>border-left-width</td><td>length</td>
1402 </tr>
1403 <tr>
1404 <td>border-right-color</td><td>color</td>
1405 </tr>
1406 <tr>
1407 <td>border-right-width</td><td>length</td>
1408 </tr>
1409 <tr>
1410 <td>border-spacing</td><td>length</td>
1411 </tr>
1412 <tr>
1413 <td>border-top-color</td><td>color</td>
1414 </tr>
1415 <tr>
1416 <td>border-top-width</td><td>length</td>
1417 </tr>
1418 <tr>
1419 <td>bottom</td><td>length, percentage</td>
1420 </tr>
1421 <tr>
1422 <td>clip</td><td>rectangle</td>
1423 </tr>
1424 <tr>
1425 <td>color</td><td>color</td>
1426 </tr>
1427 <tr>
1428 <td>crop <span class="issue">css3-content will likely advance slower than this specification, in which case this definition should move there</span></td><td>rectangle</td>
1429 </tr>
1430 <tr>
1431 <td>font-size</td><td>length, percentage</td>
1432 </tr>
1433 <tr>
1434 <td>font-weight</td><td>font weight</td>
1435 </tr>
1436 <tr>
1437 <td>height</td><td>length, percentage</td>
1438 </tr>
1439 <tr>
1440 <td>left</td><td>length, percentage</td>
1441 </tr>
1442 <tr>
1443 <td>letter-spacing</td><td>length</td>
1444 </tr>
1445 <tr>
1446 <td>line-height</td><td>number, length, percentage</td>
1447 </tr>
1448 <tr>
1449 <td>margin-bottom</td><td>length</td>
1450 </tr>
1451 <tr>
1452 <td>margin-left</td><td>length</td>
1453 </tr>
1454 <tr>
1455 <td>margin-right</td><td>length</td>
1456 </tr>
1457 <tr>
1458 <td>margin-top</td><td>length</td>
1459 </tr>
1460 <tr>
1461 <td>max-height</td><td>length, percentage</td>
1462 </tr>
1463 <tr>
1464 <td>max-width</td><td>length, percentage </td>
1465 </tr>
1466 <tr>
1467 <td>min-height</td><td>length, percentage</td>
1468 </tr>
1469 <tr>
1470 <td>min-width</td><td>length, percentage</td>
1471 </tr>
1472 <tr>
1473 <td>opacity</td><td>number</td>
1474 </tr>
1475 <tr>
1476 <td>outline-color</td><td>color</td>
1477 </tr>
1478 <tr>
1479 <td>outline-offset</td><td>length</td>
1480 </tr>
1481 <tr>
1482 <td>outline-width</td><td>length</td>
1483 </tr>
1484 <tr>
1485 <td>padding-bottom</td><td>length</td>
1486 </tr>
1487 <tr>
1488 <td>padding-left</td><td>length</td>
1489 </tr>
1490 <tr>
1491 <td>padding-right</td><td>length</td>
1492 </tr>
1493 <tr>
1494 <td>padding-top</td><td>length</td>
1495 </tr>
1496 <tr>
1497 <td>right</td><td>length, percentage</td>
1498 </tr>
1499 <tr>
1500 <td>text-indent</td><td>length, percentage</td>
1501 </tr>
1502 <tr>
1503 <td>text-shadow</td><td>shadow</td>
1504 </tr>
1505 <tr>
1506 <td>top</td><td>length, percentage</td>
1507 </tr>
1508 <tr>
1509 <td>vertical-align</td><td>length, percentage</td>
1510 </tr>
1511 <tr>
1512 <td>visibility</td><td>visibility</td>
1513 </tr>
1514 <tr>
1515 <td>width</td><td>length, percentage</td>
1516 </tr>
1517 <tr>
1518 <td>word-spacing</td><td>length, percentage</td>
1519 </tr>
1520 <tr>
1521 <td>z-index</td><td>integer</td>
1522 </tr>
1523 </table>
1525 <p class="issue">
1526 This list omits the following properties that Gecko can animate, and
1527 which likely should be included:
1528 background-size,
1529 border-*-radius,
1530 box-shadow,
1531 column-count,
1532 column-gap,
1533 column-rule-color,
1534 column-rule-width,
1535 column-width,
1536 font-size-adjust,
1537 font-stretch,
1538 marker-offset,
1539 text-decoration-color,
1540 transform,
1541 transform-origin.
1542 </p>
1544 <h3 id=animatable-svg><a id=properties-from-svg->
1545 Properties from SVG
1546 </a></h3>
1548 <p>
1549 All properties defined as animatable in the SVG specification, provided
1550 they are one of the property types listed above.
1551 </p>
1553 <!-- <table>
1554 <tr>
1555 <th>Property Name</th><th>Type</th>
1556 </tr>
1557 <tr>
1558 <td>stop-color</td><td>color</td>
1559 </tr>
1560 <tr>
1561 <td>stop-opacity</td><td>float</td>
1562 </tr>
1563 <tr>
1564 <td>fill</td><td>paint server</td>
1565 </tr>
1566 <tr>
1567 <td>fill-opacity</td><td>float</td>
1568 </tr>
1569 <tr>
1570 <td>stroke</td><td>paint server</td>
1571 </tr>
1572 <tr>
1573 <td>stroke-dasharray</td><td>list of numbers</td>
1574 </tr>
1575 <tr>
1576 <td>stroke-dashoffset</td><td>number</td>
1577 </tr>
1578 <tr>
1579 <td>stroke-miterlimit</td><td>number</td>
1580 </tr>
1581 <tr>
1582 <td>stroke-opacity</td><td>float</td>
1583 </tr>
1584 <tr>
1585 <td>stroke-width</td><td>float</td>
1586 </tr>
1587 <tr>
1588 <td>viewport-fill</td><td>color</td>
1589 </tr>
1590 <tr>
1591 <td>viewport-fill-opacity</td><td>color</td>
1592 </tr>
1593 </table> -->
1595 <h2 id="acknowledgments">Acknowledgments</h2>
1597 <p>Thanks especially to the feedback from
1598 Tab Atkins,
1599 Carine Bournez,
1600 Aryeh Gregor,
1601 Vincent Hardy,
1602 Cameron McCormack,
1603 Alex Mogilevsky,
1604 and all the rest of the
1605 <a href="http://lists.w3.org/Archives/Public/www-style/">www-style</a> community.</p>
1607 <h2 id="references">References</h2>
1609 <h3 class="no-num" id=normative-references>Normative references</h3>
1610 <!--normative-->
1612 <h3 class="no-num" id=other-references>Other references</h3>
1613 <!--informative-->
1617 <h2 class="no-num" id=property-index>Property index</h2>
1618 <!-- properties -->
1622 <h2 class="no-num" id="index">Index</h2>
1623 <!--index-->
1625 </body>
1626 </html>
1627 <!-- Keep this comment at the end of the file
1628 Local variables:
1629 mode: sgml
1630 sgml-default-doctype-name:"html"
1631 sgml-minimize-attributes:t
1632 End:
1633 -->
