Another abandoned server code base... this is kind of an ancestor of taskrambler.
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<h1 id=css-exclusions-module>CSS Exclusions and Shapes Module Level 3</h1>
<h2 class="no-num no-toc" id=longstatus-date>W3C Working Draft 13 December
2011</h2>
<dl>
<dt>This version:
<dd><a
href="http://www.w3.org/TR/2011/WD-css3-exclusions-20111213/">http://www.w3.org/TR/2011/WD-css3-exclusions-20111213/</a>
<dt>Latest version:
<dd><a
href="http://www.w3.org/TR/css3-exclusions/">http://www.w3.org/TR/css3-exclusions/</a>
<dt>Previous version:
<dd>None
<dt>Editors:
<dd class=vcard><span class=fn>Vincent Hardy</span>, <span
class=org>Adobe Systems, Inc.</span>, <span
class=email>vhardy@adobe.com</span>
<dd class=vcard><span class=fn>Rossen Atanassov</span>, <span
class=org>Microsoft Corporation</span>, <span
class=email>ratan@microsoft.com</span>
<dt>Issues List
<dd><a
href="http://wiki.csswg.org/ideas/css3-exclusions">http://wiki.csswg.org/ideas/css3-exclusions</a>
</dl>
<!--begin-copyright-->
<p class=copyright><a
href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
rel=license>Copyright</a> &copy; 2011 <a
href="http://www.w3.org/"><acronym
title="World Wide Web Consortium">W3C</acronym></a><sup>&reg;</sup> (<a
href="http://www.csail.mit.edu/"><acronym
title="Massachusetts Institute of Technology">MIT</acronym></a>, <a
href="http://www.ercim.eu/"><acronym
title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym></a>,
<a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C <a
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<a
href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a>
and <a
href="http://www.w3.org/Consortium/Legal/copyright-documents">document
use</a> rules apply.</p>
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<h2 class="no-num no-toc" id=abstract>Abstract</h2>
<p> CSS exclusions define arbitrary areas around which inline content can
flow. Unlike CSS floats, which they extend, CSS exclusions can be
positioned with any CSS positioning schemes.
<p> CSS Shapes control the geometric shapes used for wrapping inline flow
content outside or inside an element.
<p> Combining CSS Exclusions and CSS Shapes allows sophisticated layouts,
for example having content flow into and/or around circles or other,
arbitrarily complex shapes.
<h2 class="no-num no-toc" id=status>Status of this document</h2>
<!--begin-status-->
<p><em>This section describes the status of this document at the time of
its publication. Other documents may supersede this document. A list of
current W3C publications and the latest revision of this technical report
can be found in the <a href="http://www.w3.org/TR/">W3C technical reports
index at http://www.w3.org/TR/.</a></em>
<p>Publication as a Working Draft does not imply endorsement by the W3C
Membership. This is a draft document and may be updated, replaced or
obsoleted by other documents at any time. It is inappropriate to cite this
document as other than work in progress.
<p>The (<a
href="http://lists.w3.org/Archives/Public/www-style/">archived</a>) public
mailing list <a href="mailto:www-style@w3.org">www-style@w3.org</a> (see
<a href="http://www.w3.org/Mail/Request">instructions</a>) is preferred
for discussion of this specification. When sending e-mail, please put the
text &#8220;css3-exclusions&#8221; in the subject, preferably like this:
&#8220;[<!---->css3-exclusions<!---->] <em>&hellip;summary of
comment&hellip;</em>&#8221;
<p>This document was produced by the <a
href="http://www.w3.org/Style/CSS/members">CSS Working Group</a> (part of
the <a href="http://www.w3.org/Style/">Style Activity</a>).
<p>This document was produced by a group operating under the <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February
2004 W3C Patent Policy</a>. W3C maintains a <a
href="http://www.w3.org/2004/01/pp-impl/32061/status"
rel=disclosure>public list of any patent disclosures</a> made in
connection with the deliverables of the group; that page also includes
instructions for disclosing a patent. An individual who has actual
knowledge of a patent which the individual believes contains <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential
Claim(s)</a> must disclose the information in accordance with <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section
6 of the W3C Patent Policy</a>.</p>
<!--end-status-->
<p>This is the First Public Working Draft of the CSS Exclusions and Shapes
Level 3 Module.
<h2 class="no-num no-toc" id=contents>Table of contents</h2>
<!--begin-toc-->
<ul class=toc>
<li><a href="#intro"><span class=secno>1. </span>Introduction</a>
<li><a href="#definitions"><span class=secno>2. </span>Definitions</a>
<li><a href="#exclusions"><span class=secno>3. </span>Exclusions</a>
<ul class=toc>
<li><a href="#declaring-exclusions"><span class=secno>3.1.
</span>Declaring exclusions</a>
<ul class=toc>
<li><a href="#wrap-flow-property"><span class=secno>3.1.1. </span>The
&lsquo;<code class=property>wrap-flow</code>&rsquo; property</a>
</ul>
<li><a href="#scope-and-effect-of-exclusions"><span class=secno>3.2.
</span>Scope and Effect of Exclusions</a>
<ul class=toc>
<li><a href="#wrap-margin-property"><span class=secno>3.2.1.
</span>The &lsquo;<code class=property>wrap-margin</code>&rsquo;
Property</a>
<li><a href="#wrap-padding-property"><span class=secno>3.2.2.
</span>The &lsquo;<code class=property>wrap-padding</code>&rsquo;
Property</a>
</ul>
<li><a href="#propagation-of-exclusions"><span class=secno>3.3.
</span>Propagation of Exclusions</a>
<ul class=toc>
<li><a href="#wrap-through-property"><span class=secno>3.3.1.
</span>The &lsquo;<code class=property>wrap-through</code>&rsquo;
Property</a>
<li><a href="#wrap-shorthand-property"><span class=secno>3.3.2.
</span>The &lsquo;<code class=property>wrap</code>&rsquo; Shorthand
Property</a>
</ul>
<li><a href="#exclusions-order"><span class=secno>3.4. </span>Exclusions
order</a>
<li><a href="#exclusions-implementation-note"><span class=secno>3.5.
</span>Exclusions implementation note</a>
</ul>
<li><a href="#shapes"><span class=secno>4. </span>Shapes</a>
<ul class=toc>
<li><a href="#shapes-from-svg-syntax"><span class=secno>4.1.
</span>Shapes from SVG Syntax</a>
<ul class=toc>
<li><a href="#supported-svg-shapes"><span class=secno>4.1.1.
</span>Supported SVG Shapes</a>
<li><a href="#referencing-svg-shapes"><span class=secno>4.1.2.
</span>Referencing SVG shapes</a>
</ul>
<li><a href="#shapes-from-image"><span class=secno>4.2. </span>Shapes
from Image</a>
<li><a href="#declaring-shapes"><span class=secno>4.3. </span>Declaring
Shapes</a>
<ul class=toc>
<li><a href="#shape-outside-property"><span class=secno>4.3.1.
</span>The &lsquo;<code class=property>shape-outside</code>&rsquo;
Property</a>
<li><a href="#shape-inside-property"><span class=secno>4.3.2.
</span>The &lsquo;<code class=property>shape-inside</code>&rsquo;
Property</a>
<li><a href="#shape-image-threshold-property"><span class=secno>4.3.3.
</span>The &lsquo;<code
class=property>shape-image-threshold</code>&rsquo; Property</a>
</ul>
</ul>
<li><a href="#conformance"><span class=secno>5. </span>Conformance</a>
<ul class=toc>
<li><a href="#conventions"><span class=secno>5.1. </span>Document
Conventions</a>
<li><a href="#conformance-classes"><span class=secno>5.2.
</span>Conformance Classes</a>
<li><a href="#partial"><span class=secno>5.3. </span> Partial
Implementations</a>
<li><a href="#experimental"><span class=secno>5.4. </span> Experimental
Implementations</a>
<li><a href="#testing"><span class=secno>5.5. </span> Non-Experimental
Implementations</a>
<li><a href="#cr-exit-criteria"><span class=secno>5.6. </span> CR Exit
Criteria</a>
</ul>
<li class=no-num><a href="#acknowledgments">Acknowledgments</a>
<li class=no-num><a href="#references">References</a>
<ul class=toc>
<li class=no-num><a href="#normative-references">Normative
references</a>
<li class=no-num><a href="#other-references">Other references</a>
</ul>
<li class=no-num><a href="#index">Index</a>
<li class=no-num><a href="#property-index">Property index</a>
</ul>
<!--end-toc-->
<h2 id=intro><span class=secno>1. </span>Introduction</h2>
<p><em>This section is not normative.</em>
<p> The exclusions section of this specification defines features that
allow inline flow content to wrap around outside the <a
href="#exclusion-area">exclusion area</a> of elements.
<p> The shapes section of the specification defines properties to control
the geometry of an element's <a href="#exclusion-area">exclusion area</a>
as well as the geometry used for wrapping an element's inline flow
content.
<h2 id=definitions><span class=secno>2. </span>Definitions</h2>
<p><dfn id=exclusion-element>Exclusion element</dfn>
<p> An element that defines an <a href="#exclusion-area">exclusion area</a>
for other elements. The &lsquo;<a href="#wrap-flow"><code
class=property>wrap-flow</code></a>&rsquo; property is used to make an
element an exclusion element. An exclusion element contributes its <a
href="#exclusion-area">exclusion area</a> to its <a
href="http://www.w3.org/TR/CSS2/visudet.html#containing-block-details">
containing block's</a> <a href="#wrapping-context">wrapping context</a>
<p><dfn id=exclusion-area>Exclusion area</dfn>
<div class=issue-marker><a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15087">Bug-15087</a></div>
<p> The area used for excluding inline flow content around an exclusion
element. The exclusion area is equivalent to the <a
href="http://www.w3.org/TR/CSS2/box.html#box-dimensions"> border box</a>
for elements with &lsquo;<code class=property>float</code>&rsquo; property
computed to &lsquo;<code class=property>none</code>&rsquo; and the <a
href="http://www.w3.org/TR/CSS2/box.html#box-dimensions">margin box</a>
for elements with &lsquo;<code class=property>float</code>&rsquo; property
computed to a value other than &lsquo;<code
class=property>none</code>&rsquo;. This specification's &lsquo;<a
href="#shape-outside"><code class=property>shape-outside</code></a>&rsquo;
property can be used to define arbitrary, non-rectangular exclusion areas.
<p><dfn id=wrapping-context>Wrapping context</dfn>
<div class=issue-marker><a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15086">Bug-15086</a></div>
<p> The wrapping context of an element is a collection of &lsquo;<code
class=css>exclusion areas</code>&rsquo;. The wrapping context is used to
wrap around inline flow content during layout. An element will wrap its
inline flow content in the area that corresponds to the subtraction of its
wrapping context from its own <a href="#content-area">content area</a>.
<p> An element inherits its <a
href="http://www.w3.org/TR/CSS2/visudet.html#containing-block-details">containing
block's</a> wrapping context unless it specifically resets it using the
&lsquo;<a href="#wrap-through"><code
class=property>wrap-through</code></a>&rsquo; property.
<p><dfn id=content-area>Content area</dfn>
<p> The area used for layout of the inline flow content of an element. By
default the area is equivalent to the <a
href="http://www.w3.org/TR/CSS2/box.html#box-dimensions">content box</a>.
This specification's &lsquo;<a href="#shape-inside"><code
class=property>shape-inside</code></a>&rsquo; property can define
arbitrary, non-rectangular content areas.
<p><dfn id=outside-and-inside title=outside-inside>Outside and inside</dfn>
<p> In this specification, &lsquo;<code
class=property>outside</code>&rsquo; refers to DOM content that is not a
descendant of an element while &lsquo;<code
class=property>inside</code>&rsquo; refers to the element's descendants.
<h2 id=exclusions><span class=secno>3. </span>Exclusions</h2>
<p> Exclusion elements define exclusion areas that contribute to their
containing block's wrapping context. As a consequence, exclusions impact
the layout of their containing block's descendants.
<p>
<p> Elements layout their inline content in their <a
href="#content-area">content area</a> and avoid the areas in their
associated wrapping context. If the element is itself an exclusion, it
does not wrap around its own exclusion shape and the impact of other
exclusions on other exclusions is controlled by the &lsquo;<code
class=property>z-index</code>&rsquo; property as explained in the <a
href="#exclusions-order">exclusions order</a> section.
<p> The shape properties can is used to change the shape of exclusions.
<h3 id=declaring-exclusions><span class=secno>3.1. </span>Declaring
exclusions</h3>
<p> An element becomes an exclusion when its &lsquo;<a
href="#wrap-flow"><code class=property>wrap-flow</code></a>&rsquo;
property has a computed value other than &lsquo;<code
class=property>auto</code>&rsquo;.
<h4 id=wrap-flow-property><span class=secno>3.1.1. </span>The &lsquo;<a
href="#wrap-flow"><code class=property>wrap-flow</code></a>&rsquo;
property</h4>
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=wrap-flow title="'wrap-flow'">wrap-flow</dfn>
<tr>
<th>Value:
<td><var>auto</var> | <var>both</var> | <var>start</var> |
<var>end</var> | <var>maximum</var> | <var>clear</var>
<tr>
<th>Initial:
<td>auto
<tr>
<th>Applies to:
<td>block-level elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed&nbsp;value:
<td>as specified, except for floats all values compute to &lsquo;<code
class=property>auto</code>&rsquo;
</table>
<p>The values of this property have the following meanings:
<dl>
<dt><dfn id=auto title="'wrap-flow'!!'auto'">auto</dfn>
<dd> For floats an exclusion is created, for all other elements an
exclusion is not created.
<dt><dfn id=both title="'wrap-flow'!!'both'">both</dfn>
<dd> Inline flow content can flow on all sides of the exclusion.
<dt><dfn id=start title="'wrap-flow'!!'start'">start</dfn>
<dd> Inline flow content can wrap on the start edge of the exclusion area
but must leave the area to end edge of the exclusion area empty.
<dt><dfn id=end title="'wrap-flow'!!'end'">end</dfn>
<dd> Inline flow content can wrap on the end side of the exclusion area
but must leave the area to the start edge of the exclusion area empty.
<dt><dfn id=maximum title="'wrap-flow'!!'maximum'">maximum</dfn>
<dd> Inline flow content can wrap on the side of the exclusion with the
largest available space for the given line, and must leave the other side
of the exclusion empty.
<dt><dfn id=clear title="'wrap-flow'!!'clear'">clear</dfn>
<dd> Inline flow content can only wrap on top and bottom of the exclusion
and must leave the areas to the start and end edges of the exclusion box
empty.
</dl>
<p> Setting the &lsquo;<a href="#wrap-flow"><code
class=property>wrap-flow</code></a>&rsquo; property to &lsquo;<code
class=property>both</code>&rsquo;, &lsquo;<code
class=property>start</code>&rsquo;, &lsquo;<code
class=property>end</code>&rsquo;, &lsquo;<code
class=property>maximum</code>&rsquo; or &lsquo;<code
class=property>clear</code>&rsquo; on an element makes that element an
<span>exclusion element. It's <span>exclusion shape</span> is contributed
to its containing block's wrapping context, causing the containing block's
descendants to wrap around its exclusion area. </span>
<p> The initial value for this property is &lsquo;<code
class=property>auto</code>&rsquo;.
<p> When the property's computed value is &lsquo;<code
class=property>auto</code>&rsquo;, the element does not become an <a
href="#exclusion-element">exclusion element</a> unless its &lsquo;<code
class=property>float</code>&rsquo; property computed value is not
&lsquo;<code class=property>none</code>&rsquo;. In that case, the element
contributes its &lsquo;<code class=css>border box</code>&rsquo; to its
containing block's <a href="#wrapping-context">wrapping context</a> and
content flows around it according to the &lsquo;<code
class=property>clear</code>&rsquo; property.
<p> The element will be considered as an exclusion for all inline flow
content descendants of the exclusions' containing block.
<div class=figure> <img
alt="General illustration showing how exclusions combine"
src="images/exclusions-illustration.png" width="70%">
<p class=caption>Combining exclusions</p>
</div>
<div>
<p>The above figure illustrates how exclusions combine. The red box
represents an element's content box. The A, B, C and D darker gray boxes
represent exclusions in the element's wrapping context. A, B, C and D
have their respective &lsquo;<a href="#wrap-flow"><code
class=property>wrap-flow</code></a>&rsquo; set to &lsquo;<code
class=property>both</code>&rsquo;, &lsquo;<code
class=property>start</code>&rsquo;, &lsquo;<code
class=property>end</code>&rsquo; and &lsquo;<code
class=property>clear</code>&rsquo; respectively. The lighter gray areas
show the additional areas that are excluded for inline layout as a result
of the &lsquo;<a href="#wrap-flow"><code
class=property>wrap-flow</code></a>&rsquo; value. For example, the area
to the right of &lsquo;<code class=property>B</code>&rsquo; cannot be
used for inline layout because the &lsquo;<a href="#wrap-flow"><code
class=property>wrap-flow</code></a>&rsquo; for &lsquo;<code
class=property>B</code>&rsquo; is &lsquo;<code
class=property>start</code>&rsquo;.</p>
<p>The background &lsquo;<code class=property>blue</code>&rsquo; area
shows what areas are available for inline content layout. All areas
represented with a light or dark shade of gray are not available for
inline content layout.</p>
</div>
<div class=issue-marker><a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15088">Bug-15088</a></div>
<div class=issue-marker><a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15084">Bug-15084</a></div>
<div class=example>
<p> The &lsquo;<a href="#wrap-flow"><code
class=property>wrap-flow</code></a>&rsquo; property values applied to an
absolutely positioned element.</p>
<code class=html></code>
<pre>
&lt;style type="text/css"&gt;
#exclusion {
position: absolute;
background: lightblue;
border: 3px solid blue;
}
&lt;/style&gt;
&lt;div style=”position: relative; border: 1px solid black;”&gt;
&lt;div id=”exclusion”&gt;Donec metus messa, mollis...&lt;/div&gt;
Lorem ipsum dolor sit amet...
&lt;/div&gt;
</pre>
<table class=example-table>
<tbody>
<tr>
<td><code class=html>#exclusion{ wrap-flow: auto; }</code>
<td><code class=html>#exclusion{ wrap-flow: both; }</code>
<tr>
<td><img alt="Example rendering for wrap-side: auto"
src="images/exclusion_wrap_side_auto.png">
<td><img alt="Example rendering for wrap-side: both"
src="images/exclusion_wrap_side_both.png">
<tr>
<td><code class=html>#exclusion{ wrap-flow: start; }</code>
<td><code class=html>#exclusion{ wrap-flow: end; }</code>
<tr>
<td><img alt="Example rendering for wrap-side: start"
src="images/exclusion_wrap_side_left.png">
<td><img alt="Example rendering for wrap-side: end"
src="images/exclusion_wrap_side_right.png">
<tr>
<td><code class=html>#exclusion{ wrap-flow: maximum; }</code>
<td><code class=html>#exclusion{ wrap-flow: maximum; }</code>
<tr>
<td><img alt="Example rendering for wrap-side: maximum"
src="images/exclusion_wrap_side_maximum_L.png">
<td><img alt="Example rendering for wrap-side: maximum"
src="images/exclusion_wrap_side_maximum_R.png">
<tr>
<td><code class=html>#exclusion{ wrap-flow: clear; }</code>
<td><code class=html>&nbsp;</code>
<tr>
<td><img alt="Example rendering for wrap-side: clear"
src="images/exclusion_wrap_side_clear.png">
<td>&nbsp;
</table>
</div>
<!-- End section "wrap-flow Property" -->
<!-- End section "Declaring Exclusions" -->
<h3 id=scope-and-effect-of-exclusions><span class=secno>3.2. </span>Scope
and Effect of Exclusions</h3>
<p> An exclusion affects the inline flow content descended from the
exclusion's containing blocks (defined in <a
href="http://www.w3.org/TR/CSS2/visudet.html#containing-block-details">
CSS 2.1 10.1</a>) and that of all descendant elements of the same
containing block. All inline flow content inside the containing block of
the exclusions is affected. To stop the effect of exclusions defined
outside any element, the &lsquo;<a href="#wrap-through"><code
class=property>wrap-through</code></a>&rsquo; property can be used (see
definition of Propagation of Exclusions below).
<h4 id=wrap-margin-property><span class=secno>3.2.1. </span>The &lsquo;<a
href="#wrap-margin"><code class=property>wrap-margin</code></a>&rsquo;
Property</h4>
<p> The &lsquo;<a href="#wrap-margin"><code
class=property>wrap-margin</code></a>&rsquo; property can be used to
offset the inline flow content wrapping on the outside of exclusions.
Offsets created by the &lsquo;<a href="#wrap-margin"><code
class=property>wrap-margin</code></a>&rsquo; property are offset from the
outside of the exclusion. This property takes on positive values only.
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=wrap-margin title="'wrap-margin'">wrap-margin</dfn>
<tr>
<th>Value:
<td><var>&lt;length&gt;</var>
<tr>
<th>Initial:
<td>0
<tr>
<th>Applies to:
<td>block-level elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed&nbsp;value:
<td>the absolute length
</table>
<!-- End secion "wrap-margin property" -->
<h4 id=wrap-padding-property><span class=secno>3.2.2. </span>The &lsquo;<a
href="#wrap-padding"><code class=property>wrap-padding</code></a>&rsquo;
Property</h4>
<p> The &lsquo;<a href="#wrap-padding"><code
class=property>wrap-padding</code></a>&rsquo; property can be used to
offset to the inline flow content wrapping on the inside of elements.
Offsets created by the &lsquo;<a href="#wrap-padding"><code
class=property>wrap-padding</code></a>&rsquo; property are offset from the
<a href="#content-area">content area</a> of the element. This property
takes on positive values only.
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=wrap-padding title="'wrap-padding'">wrap-padding</dfn>
<tr>
<th>Value:
<td><var>&lt;length&gt;</var>
<tr>
<th>Initial:
<td>0
<tr>
<th>Applies to:
<td>block-level elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed&nbsp;value:
<td>the absolute length
</table>
<!-- End section "wrap-padding property" -->
<div class=note>Note that the &lsquo;<a href="#wrap-padding"><code
class=property>wrap-padding</code></a>&rsquo; property affects layout of
content inside the element it applies to while the &lsquo;<a
href="#wrap-margin"><code class=property>wrap-margin</code></a>&rsquo;
property affects layout of content outside the element.</div>
<!-- End section "Scope and Effect of Exclusions" -->
<h3 id=propagation-of-exclusions><span class=secno>3.3. </span>Propagation
of Exclusions</h3>
<p> By default, an element inherits its parent <a
href="#wrapping-context">wrapping context</a>. In other words it is
subject to the exclusions defined <a href="#outside-and-inside"
title=outside-inside>outside the element. </a>
<p>Setting the &lsquo;<a href="#wrap-through"><code
class=property>wrap-through</code></a>&rsquo; property to &lsquo;<code
class=property>none</code>&rsquo; prevents an element from inheriting its
parent wrapping context. In other words, exclusions defined &lsquo;<code
class=property>outside</code>&rsquo; the element, have not effect on the
element's children layout.
<div class=note> Exclusions defined by an element's descendants still
contribute to their containing block's <a
href="#wrapping-context">wrapping context</a>. If that containing block is
a child of an element with &lsquo;<a href="#wrap-through"><code
class=property>wrap-through</code></a>&rsquo; set to none, or the element
itself, then exclusion still have an effect on the children of that
containing block element.</div>
<h4 id=wrap-through-property><span class=secno>3.3.1. </span>The &lsquo;<a
href="#wrap-through"><code class=property>wrap-through</code></a>&rsquo;
Property</h4>
<div class=issue-marker><a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15085">Bug-15085</a></div>
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=wrap-through title="'wrap-through'">wrap-through</dfn>
<tr>
<th>Value:
<td><a href="#wrap0"><var>wrap</var></a> | <var>none</var>
<tr>
<th>Initial:
<td>wrap
<tr>
<th>Applies to:
<td>block-level elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed&nbsp;value:
<td>as specified
</table>
<p>The values of this property have the following meanings:
<dl>
<dt><dfn id=wrap title="'wrap-through'!!'wrap'">wrap</dfn>
<dd> The element inherits its parent node's <a
href="#wrapping-context">wrapping context</a>. Its descendant inline
content wraps around exclusions defined <a href="#outside-and-inside"
title=outside-inside>outside</a> the element.
</dl>
<dl>
<dt><dfn id=none title="'wrap-through'!!'none'">none</dfn>
<dd> The element does not inherit its parent node's <a
href="#wrapping-context">wrapping context</a>. Its descendants are only
subject to exclusion shapes defined <a href="#outside-and-inside"
title=outside-inside>inside</a> the element.
</dl>
<div class=example>
<p> Using the &lsquo;<a href="#wrap-through"><code
class=property>wrap-through</code></a>&rsquo; property to control the
effect of exclusions.</p>
<pre><code class=html>
&lt;style type="text/css"&gt;
.exclusion {
wrap-flow: both;
position: absolute;
background-color: rgba(220, 230, 242, 0.5);
}
&lt;/style&gt;
&lt;div style=”position: relative;”&gt;
&lt;div class=”exclusion”&gt;&lt;/div&gt;
&lt;div style=”wrap-through: wrap;”&gt; Lorem ipsum dolor sit amet...&lt;/div&gt;
&lt;div style=”wrap-through: none;”&gt; Lorem ipsum dolor sit amet...&lt;/div&gt;
&lt;/div&gt;
</code></pre>
<img alt="Example rendering of wrap-through: wrap | none"
class=singleImgExample src="images/exclusion_wrap_through.png"
style="max-width:40%"></div>
<!-- End section "wrap-through property" -->
<h4 id=wrap-shorthand-property><span class=secno>3.3.2. </span>The
&lsquo;<a href="#wrap0"><code class=property>wrap</code></a>&rsquo;
Shorthand Property</h4>
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=wrap0 title="'wrap'">wrap</dfn>
<tr>
<th>Value:
<td><var>&lt;wrap-flow&gt;</var> || <var>&lt;wrap-margin&gt;</var> [ /
<var>&lt;wrap-padding&gt;</var>]
<tr>
<th>Initial:
<td>see individual properties
<tr>
<th>Applies to:
<td>block-level elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed&nbsp;value:
<td>see individual properties
</table>
<p> The &lsquo;<a href="#wrap0"><code class=property>wrap</code></a>&rsquo;
property is a shorthand property for setting the exclusions properties at
the same place in the style sheet.</p>
<!-- End section "wrap shorthand property" -->
<!-- End section "Propagation of Exclusions" -->
<h3 id=exclusions-order><span class=secno>3.4. </span>Exclusions order</h3>
<p> Exclusions follow the painting order (See <a href="#CSS21"
rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a> Appendix E). Exclusions are
applied in reverse to the document order in which they are defined. The
last exclusion appears on top of all other exclusion, thus it affects the
inline flow content of all other preceding exclusions or elements
descendant of the same containing block. To change the ordering of
exclusions with &lsquo;<code class=property>position</code>&rsquo;
property computed to a value other than &lsquo;<code
class=property>static</code>&rsquo;, &lsquo;<code
class=property>z-index</code>&rsquo; can be used. Exclusions with
&lsquo;<code class=property>position</code>&rsquo; property computed to
&lsquo;<code class=property>static</code>&rsquo; are not affected by the
&lsquo;<code class=property>z-index</code>&rsquo; property, thus follow
the painting order.
<div class=example>
<p>Ordering of exclusions.</p>
<pre><code class=html>
&lt;style type="text/css"&gt;
.exclusion {
wrap-flow: both;
position: absolute;
width: 50%;
height: 50%;
}
&lt;/style&gt;
&lt;div class=”exclusion” style=”top: 0px; left: 0px;”&gt;
Lorem ipsum dolor sit amet...
&lt;/div&gt;
&lt;div id="orderedExclusion" class=”exclusion” style=”top: 25%; left: 25%;”&gt;
Lorem ipsum dolor sit amet...
&lt;/div&gt;
&lt;div class=”exclusion” style=”top: 50%; left: 50%;”&gt;
Lorem ipsum dolor sit amet...
&lt;/div&gt;
</code></pre>
<table class=example-table>
<tbody>
<tr>
<td style="width:50%"><code class=html>#orderedExclusion{ z-index:
auto; }</code>
<td style="width:50%"><code class=html>#orderedExclusion{ z-index: 1;
}</code>
<tr>
<td><img alt="Example rendering of default exclusion ordering."
class=singleImgExample src="images/exclusion_ordering.png">
<td><img alt="Example rendering of default exclusion ordering."
class=singleImgExample src="images/exclusion_ordering_z_order.png">
</table>
</div>
<!-- End section "Order of Exclusions" -->
<h3 id=exclusions-implementation-note><span class=secno>3.5.
</span>Exclusions implementation note</h3>
<div class=issue-marker><a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15083">Bug-15083</a></div>
<p><em>This section is not normative.</em>
<p> Exclusions can be specified on positioned elements and elements can be
positioned from their <a
href="http://www.w3.org/TR/CSS21/visudet.html#static-position">static
position</a>. Since, the static position of such elements depends on the
inline flow content affected by the exclusion itself; there is a circular
dependency between the two layout tasks. To break this circular dependency
a two-pass layout approach is recommended. The first layout pass computes
the static positions of all auto-positioned exclusions by laying out all
content besides exclusions. The second pass is layout of all elements
including all exclusions. Exclusions that depend on their static position
will use the position calculated during the first layout pass.
<p class=note> Note, this may cause exclusions to overlap or be distant
from their static position (compared to non-exclusions auto-positioned
elements).
<p> Similar dependency exists for exclusions whose size or position is
specified in percentage and the containing block size is specified as
&lsquo;<code class=property>auto</code>&rsquo;. In such cases the size or
position of the exclusion is calculated based on the size of the
containing block calculated in the first layout pass.
<p> Exclusions can be positioned on all levels of nested elements. If
layout is restarted on every level of nesting, the time to complete layout
will be exponential. To avoid multiple layout passes, the restart of the
second layout pass should be scoped to the top-most containing block of
exclusions. Similarly, restarting layout for the entire document is not
necessary unless there are exclusions whose containing block is the
initial containing block.</p>
<!-- End section "Processing Model of Exclusions" -->
<!-- End section "Exclusions" -->
<h2 id=shapes><span class=secno>4. </span>Shapes</h2>
<div class=issue-marker> <a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15091">Bug-15091</a><br>
</div>
<p> Shapes define arbitrary geometric contours around which or into which
inline flow content flows. There are two different types of shapes –
&lsquo;<code class=property>outside</code>&rsquo; and &lsquo;<code
class=property>inside</code>&rsquo;. The outside shape defines the <a
href="#exclusion-area">exclusion area</a> for an <a
href="#exclusion-element">exclusion element</a>. The inside shape defines
an element's <span>content shape</span> and the element's inline content
will flow within that shape.
<p><dfn id=flow-container>Flow Container</dfn>
<p> A flow container is an element with a &lsquo;<code
class=property>display</code>&rsquo; value that is computed as
&lsquo;<code class=property>block</code>&rsquo;, &lsquo;<code
class=property>table-cell</code>&rsquo; or &lsquo;<code
class=property>inline-block</code>&rsquo;.
<p class=note> Note, while the boundaries used for wrapping inline flow
content outside and inside an element can be defined using shapes, the
actual box model does not change. If the element has specified margins,
borders or paddings they will be computed and rendered according to the
[[CSS3-Box]] module.
<div class=example>
<p>CSS &lsquo;<code class=property>shape</code>&rsquo; and CSS box model
relation.</p>
<pre><code class=html>
&lt;style type="text/css"&gt;
.exclusion {
wrap-flow: both;
position: absolute;
shape-outside: circle(50%, 50%, 50%);
border: 1px solid red;
}
&lt;/style&gt;
&lt;div style=”position: relative; border: 1px solid black;”&gt;
&lt;div class=”exclusion”&gt;&lt;/div&gt;
Lorem ipsum dolor sit amet...
&lt;/div&gt;
</code></pre>
<img alt="Example rendering of circle shape and box model."
class=singleImgExample src="images/shapes_CSS2.1_MBP.png"
style="max-width:40%"></div>
<h3 id=shapes-from-svg-syntax><span class=secno>4.1. </span>Shapes from SVG
Syntax</h3>
<p> Shapes can be specified using <a
href="http://www.w3.org/TR/SVG/shapes.html">SVG basic shapes</a>.
<h4 id=supported-svg-shapes><span class=secno>4.1.1. </span>Supported SVG
Shapes</h4>
<p> The following SVG shapes are supported by the CSS shapes module.
<dl>
<dt>rectangle(x, y, width, height, [[rx], ry])
<dd>
<ul>
<li><strong>x, y, width and height</strong> - define the bounding box of
the rectangle
<li><strong>rx</strong> - For rounded rectangles, the x-axis radius of
the ellipse used to round off the corners of the rectangle
<li><strong>ry</strong> - For rounded rectangles, the y-axis radius of
the ellipse used to round off the corners of the rectangle
</ul>
<dt>circle(cx, cy, r)
<dd>
<ul>
<li><strong>cx</strong> - The x-axis coordinate of the center of the
circle
<li><strong>cy</strong> - The y-axis coordinate of the center of the
circle
<li><strong>r</strong> - The radius of the circle
</ul>
<dt>ellipse(cx, cy, rx, ry)
<dd>
<ul>
<li><strong>cx</strong> - The x-axis coordinate of the center of the
ellipse
<li><strong>cy</strong> - The y-axis coordinate of the center of the
ellipse
<li><strong>rx</strong> - The x-axis radius of the ellipse
<li><strong>ry</strong> - The y-axis radius of the ellipse
</ul>
<dt>polygon([fillRule], x1, y1, x2, y2, x3, y3, … xn, yn)
<dd>
<ul>
<li><strong>fillRule</strong> - The filling rule used to determine the
interior of the polygon. See fill-rule property in SVG for details.
Possible values are nonzero or evenodd. Default value when omitted is
nonzero.
<li><strong>xi</strong> - The x-axis coordinate of the i-th vertex of
the polygon
<li><strong>yi</strong> - The y-axis coordinate of the i-th vertex of
the polygon
</ul>
<p> If the polygon is not closed the user-agent will automatically add a
new vertex at the end.</p>
<br>
</dl>
<h4 id=referencing-svg-shapes><span class=secno>4.1.2. </span>Referencing
SVG shapes</h4>
<p>An SVG shape can be referenced using the <code>url()</code> syntax. The
shape can be any of the <a href="http://www.w3.org/TR/SVG/shapes.html">SVG
basic shapes</a> or a <a href="http://www.w3.org/TR/SVG/paths.html">path
element</a>.
<p>In all cases, percentages are resolved from the border box of the
element.
<div class=example> <code class=html></code>
<pre>
&lt;style&gt;
.in-a-circle {
shape-inside: url(#circle_shape);
}
.in-a-path {
shape-inside: url(#path-shape);
}
&lt;/style&gt;
&lt;svg ...&gt;
&lt;circle id="circle_shape" cx="50%x" cy="50%" r="50%" /&gt;
&lt;path id="path-shape" d="..." /&gt;
&lt;/svg&gt;
&lt;div class="in-a-circle"&gt;...&lt;/div&gt;
&lt;div class="in-a-path"&gt;...&lt;/div&gt;
</pre>
</div>
<p> When using the SVG syntax or referencing SVG elements to define shapes,
all the lengths expressed in percentages are resolved from the border box
of the element. The coordinate system for the shape has its origin on the
top-left corder of the border box with the x-axis running to the right and
the y-axis running downwards. If the SVG element uses unitless coordinate
values, they are equivalent to using &lsquo;<code
class=property>px</code>&rsquo; units. If the border box of the element is
dependent on auto sizing (i.e., the element's &lsquo;<code
class=property>width</code>&rsquo; or &lsquo;<code
class=property>height</code>&rsquo; property is &lsquo;<code
class=property>auto</code>&rsquo;), then the percentage values are
computed agains &lsquo;<code class=css>0</code>&rsquo; and resolve to 0.</p>
<!-- End section "Shapes from SVG Syntax -->
<h3 id=shapes-from-image><span class=secno>4.2. </span>Shapes from Image</h3>
<div class=issue-marker> <a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15093">Bug-15093</a><br>
<a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15090">Bug-15090</a><br>
<a
href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15092">Bug-15092</a></div>
<p> Another way of defining shapes is by specifying a source image whose
alpha channel is used to compute the inside or outside shape. The shape is
computed to be the path that encloses the area where the opacity of the
specified image is greater than the &lsquo;<a
href="#shape-image-threshold"><code
class=property>shape-image-threshold</code></a>&rsquo; value. If the
&lsquo;<a href="#shape-image-threshold"><code
class=property>shape-image-threshold</code></a>&rsquo; is not specified,
the initial value to be considered is 0.5.
<p class=note> Note, images can define cavities and inline flow content
should wrap inside them. In order to avoid that, another exclusion element
can be overlaid.</p>
<!-- End section "Shapes from image" -->
<h3 id=declaring-shapes><span class=secno>4.3. </span>Declaring Shapes</h3>
<p> Shapes are declared with the &lsquo;<a href="#shape-outside"><code
class=property>shape-outside</code></a>&rsquo; or &lsquo;<a
href="#shape-inside"><code class=property>shape-inside</code></a>&rsquo;
properties. The &lsquo;<a href="#shape-outside"><code
class=property>shape-outside</code></a>&rsquo; property changes the
geometry of an <a href="#exclusion-element">exclusion
element</a>&lsquo;<code class=css>s <span>exclusion are</span>. If the
element is not an <a href="#exclusion-element">exclusion element</a> (see
the </code>&rsquo;wrap-flow' property), then the &lsquo;<a
href="#shape-outside"><code class=property>shape-outside</code></a>&rsquo;
property has no effect.
<p> The &lsquo;<a href="#shape-inside"><code
class=property>shape-inside</code></a>&rsquo; property defines an
element's <a href="#content-area">content area</a> and the element's
inline flow content wraps into that shape.
<h4 id=shape-outside-property><span class=secno>4.3.1. </span>The &lsquo;<a
href="#shape-outside"><code class=property>shape-outside</code></a>&rsquo;
Property</h4>
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=shape-outside title="'shape-outside'">shape-outside</dfn>
<tr>
<th>Value:
<td><var>auto</var> | <var>&lt;shape&gt;</var> | <var>&lt;uri&gt;</var>
<tr>
<th>Initial:
<td>auto
<tr>
<th>Applies to:
<td>block-level elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed&nbsp;value:
<td>computed lengths for &lt;shape&gt;, the absolute URI for
&lt;uri&gt;, otherwise as specified
</table>
<p>The values of this property have the following meanings:
<dl>
<dt><dfn id=auto0 title="'shape-outside'!!'auto'">auto</dfn>
<dd>The shape is computed based on the border box of the element.
</dl>
<dl>
<dt><dfn id=ltshapegt
title="'shape-outside'!!'&lt;shape&gt;'">&lt;shape&gt;</dfn>
<dd> The shape is computed based on the values of one of &lsquo;<code
class=property>rectangle</code>&rsquo;,&lsquo;<code class=css>
circle</code>&rsquo;, &lsquo;<code class=property>ellipse</code>&rsquo;
or &lsquo;<code class=property>polygon</code>&rsquo;.
</dl>
<dl>
<dt><dfn id=lturigt
title="'shape-outside'!!'&lt;uri&gt;'">&lt;uri&gt;</dfn>
<dd> If the &lt;uri&gt; references an SVG shape element, that element
defines the shape. Otherwise, if the &lt;uri&gt; references an image, the
shape is extracted and computed based on the alpha channel of the
specified image. If the &lt;uri&gt; does not reference an SVG shape
element or an image, the effect is as if the value &lsquo;<code
class=property>auto</code>&rsquo; had been specified.
</dl>
<div class=figure> <img
alt="arbitrary shapes for excluions. Illustrates how content flows around shapes"
src="images/shapes-exclusions.png" width="70%">
<p class=caption>Arbitrary shapes for exclusions</p>
</div>
<div>
<p>The above figure shows how &lsquo;<a href="#shape-outside"><code
class=property>shape-outside</code></a>&rsquo; shapes impact the
exclusion areas. The red box represents an element's content box and
&lsquo;<code class=property>A</code>&rsquo;, &lsquo;<code
class=property>B</code>&rsquo;, &lsquo;<code
class=property>C</code>&rsquo; and &lsquo;<code
class=property>C</code>&rsquo; represent exclusions with a complex shape
and their &lsquo;<a href="#wrap-flow"><code
class=property>wrap-flow</code></a>&rsquo; property set to &lsquo;<code
class=property>both</code>&rsquo;, &lsquo;<code
class=property>start</code>&rsquo;, &lsquo;<code
class=property>end</code>&rsquo; and &lsquo;<code
class=property>clear</code>&rsquo;, respectively.</p>
<p>As illustrated in the picture, when an exclusion allows wrapping on all
sides, text can flow inside &lsquo;<code
class=property>holes</code>&rsquo; in the exclusion (as for exclusion
&lsquo;<code class=property>A</code>&rsquo;). Otherwise, the exclusion
clears the area on the side(s) defined by wrap flow, as illustrated for
&lsquo;<code class=property>B</code>&rsquo;, &lsquo;<code
class=property>C</code>&rsquo; and &lsquo;<code
class=property>D</code>&rsquo; above.</p>
</div>
<!-- End section "The shape-outside Property" -->
<h4 id=shape-inside-property><span class=secno>4.3.2. </span>The &lsquo;<a
href="#shape-inside"><code class=property>shape-inside</code></a>&rsquo;
Property</h4>
<p> The &lsquo;<a href="#shape-inside"><code
class=property>shape-inside</code></a>&rsquo; modifies the shape of the
inner inline flow content from rectangular content box to an arbitrary
geometry.
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=shape-inside title="'shape-inside'">shape-inside</dfn>
<tr>
<th>Value:
<td><var>outside-shape</var> | <var>auto</var> |
<var>&lt;shape&gt;</var> | <var>&lt;uri&gt;</var>
<tr>
<th>Initial:
<td>outside-shape
<tr>
<th>Applies to:
<td>block-level elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed&nbsp;value:
<td>computed lengths for &lt;shape&gt;, the absolute URI for
&lt;uri&gt;, otherwise as specified
</table>
<p>The values of this property have the following meanings:
<dl>
<dt><dfn id=outside-shape
title="'shape-inside'!!'outside-shape'">outside-shape</dfn>
<dd> The shape is computed based on the computed value of the &lsquo;<a
href="#shape-outside"><code
class=property>shape-outside</code></a>&rsquo; property.
</dl>
<dl>
<dt><dfn id=auto1 title="'shape-inside'!!'auto'">auto</dfn>
<dd> The shape is computed based on the content box of the element.
</dl>
<dl>
<dt><dfn id=ltshapegt0
title="'shape-inside'!!'&lt;shape&gt;'">&lt;shape&gt;</dfn>
<dd> The shape is computed based on the values of one of &lsquo;<code
class=property>rectangle</code>&rsquo;,&lsquo;<code class=css>
circle</code>&rsquo;, &lsquo;<code class=property>ellipse</code>&rsquo;
or &lsquo;<code class=property>polygon</code>&rsquo;.
</dl>
<dl>
<dt><dfn id=lturigt0
title="'shape-inside'!!'&lt;uri&gt;'">&lt;uri&gt;</dfn>
<dd> If the &lt;uri&gt; references an SVG shape element, that element
defines the shape. Otherwise, if the &lt;uri&gt; references an image, the
shape is extracted and computed based on the alpha channel of the
specified image. If the &lt;uri&gt; does not reference an SVG shape
element or an image, the effect is as if the value &lsquo;<code
class=property>auto</code>&rsquo; had been specified.
</dl>
<!-- End section "The shape-inside property" -->
<h4 id=shape-image-threshold-property><span class=secno>4.3.3. </span>The
&lsquo;<a href="#shape-image-threshold"><code
class=property>shape-image-threshold</code></a>&rsquo; Property</h4>
<p> The &lsquo;<a href="#shape-image-threshold"><code
class=property>shape-image-threshold</code></a>&rsquo; defines the alpha
channel threshold used to extract the shape using an image. A value of 0.5
means that all the pixels that are more than 50% transparent define the
path of the exclusion shape. The &lsquo;<a
href="#shape-image-threshold"><code
class=property>shape-image-threshold</code></a>&rsquo; applies to both
&lsquo;<a href="#shape-outside"><code
class=property>shape-outside</code></a>&rsquo; and &lsquo;<a
href="#shape-inside"><code class=property>shape-inside</code></a>&rsquo;.
<p class=note> The specified value of &lsquo;<a
href="#shape-image-threshold"><code
class=property>shape-image-threshold</code></a>&rsquo; is applied to both
images used for &lsquo;<a href="#shape-outside"><code
class=property>shape-outside</code></a>&rsquo; and &lsquo;<a
href="#shape-inside"><code class=property>shape-inside</code></a>&rsquo;.
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=shape-image-threshold
title="'shape-image-threshold'">shape-image-threshold</dfn>
<tr>
<th>Value:
<td><var>&lt;alphavalue&gt;</var>
<tr>
<th>Initial:
<td>0.5
<tr>
<th>Applies to:
<td>block-level elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>alpha channel of the image specified by &lt;uri&gt;
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed&nbsp;value:
<td>The same as the specified value after clipping the
&lt;alphavalue&gt; to the range [0.0,1.0].
</table>
<p>The values of this property have the following meanings:
<dl>
<dt><dfn id=ltalphavaluegt
title="'shape-image-threshold'!!'&lt;alphavalue&gt;'">&lt;alphavalue&gt;</dfn>
<dd> A &lt;number&gt; value used to set the threshold used for extracting
a shape from an image. Any values outside the range 0.0 (fully
transparent) to 1.0 (fully opaque) will be clamped to this range.
</dl>
<!-- End section "The shape-image-threshold property" -->
<!--
<h4 id="shape-shorthand-property">The 'shape' Shorthand Property</h4>
<table class="propdef">
<tr>
<th>Name:</th>
<td><dfn title="'shape'">shape</dfn></td>
</tr>
<tr>
<th>Value:</th>
<td><var>&lt;shape-outside&gt;</var> [ / <var>&lt;shape-inside&gt;</var> ] || <var>&lt;shape-image-threshold&gt;</var></td>
</tr>
<tr>
<th>Initial:</th>
<td>see individual properties</td>
</tr>
<tr>
<th>Applies to:</th>
<td>block-level elements</td>
</tr>
<tr>
<th>Inherited:</th>
<td>no</td>
</tr>
<tr>
<th>Percentages:</th>
<td>N/A</td>
</tr>
<tr>
<th>Media:</th>
<td>visual</td>
</tr>
<tr>
<th>Computed&nbsp;value:</th>
<td>see individual properties</td>
</tr>
</table>
<p>
The 'shape' property is a shorthand property for setting the individual shape properties
at the same place in a style sheet.
</p>
<div class="example">
<p>Style declaration using the 'shape' shorthand property.</p>
<pre><code class="html">
&lt;style type="text/css"&gt;
.shape {
shape: rectangle(50px, 50px, 200px, 100px) / url("shape_image.png") 0.7;
}
&lt;/style&gt
</code></pre>
</div>
<p class="issue">The example above must be finished.</p>
-->
<!-- End section "Shape Shorthand property -->
<!-- End section "Declaring Shapes" -->
<!-- End section "Shapes" -->
<h2 id=conformance><span class=secno>5. </span>Conformance</h2>
<h3 id=conventions><span class=secno>5.1. </span>Document Conventions</h3>
<p> Conformance requirements are expressed with a combination of
descriptive assertions and RFC 2119 terminology. The key words “MUST”,
“MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”,
“SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and
“OPTIONAL” in the normative parts of this document are to be
interpreted as described in RFC 2119. However, for readability, these
words do not appear in all uppercase letters in this specification.
<p> All of the text of this specification is normative except sections
explicitly marked as non-normative, examples, and notes. <a
href="#RFC2119" rel=biblioentry>[RFC2119]<!--{{!RFC2119}}--></a>
<p> Examples in this specification are introduced with the words “for
example” or are set apart from the normative text with
<code>class="example"</code>, like this:
<div class=example>
<p>This is an example of an informative example.</p>
</div>
<p> Informative notes begin with the word “Note” and are set apart from
the normative text with <code>class="note"</code>, like this:
<p class=note>Note, this is an informative note.
<h3 id=conformance-classes><span class=secno>5.2. </span>Conformance
Classes</h3>
<p>Conformance to CSS Exclusions and Shapes is defined for three
conformance classes:
<dl>
<dt><dfn id=style-sheet title="style sheet!!as conformance class">style
sheet</dfn>
<dd> A <a href="http://www.w3.org/TR/CSS21/conform.html#style-sheet">CSS
style sheet</a>.
<dt><dfn id=renderer>renderer</dfn>
<dd> A <a href="http://www.w3.org/TR/CSS21/conform.html#user-agent">UA</a>
that interprets the semantics of a style sheet and renders documents that
use them.
<dt><dfn id=authoring-tool>authoring tool</dfn>
<dd> A <a href="http://www.w3.org/TR/CSS21/conform.html#user-agent">UA</a>
that writes a style sheet.
</dl>
<p> A style sheet is conformant to CSS Exclusions and Shapes if all of its
declarations that use properties defined in this module have values that
are valid according to the generic CSS grammar and the individual grammars
of each property as given in this module.
<p> A renderer is conformant to CSS Exclusions and Shapes if, in addition
to interpreting the style sheet as defined by the appropriate
specifications, it supports all the features defined by CSS Exclusions and
Shapes by parsing them correctly and rendering the document accordingly.
However, the inability of a UA to correctly render a document due to
limitations of the device does not make the UA non-conformant. (For
example, a UA is not required to render color on a monochrome monitor.)
<p> An authoring tool is conformant to CSS Exclusions and Shapes if it
writes style sheets that are syntactically correct according to the
generic CSS grammar and the individual grammars of each feature in this
module, and meet all other conformance requirements of style sheets as
described in this module.
<h3 id=partial><span class=secno>5.3. </span> Partial Implementations</h3>
<p> So that authors can exploit the forward-compatible parsing rules to
assign fallback values, CSS renderers <strong>must</strong> treat as
invalid (and <a href="http://www.w3.org/TR/CSS21/conform.html#ignore">
ignore as appropriate</a>) any at-rules, properties, property values,
keywords, and other syntactic constructs for which they have no usable
level of support. In particular, user agents <strong>must not</strong>
selectively ignore unsupported component values and honor supported values
in a single multi-value property declaration: if any value is considered
invalid (as unsupported values must be), CSS requires that the entire
declaration be ignored.
<h3 id=experimental><span class=secno>5.4. </span> Experimental
Implementations</h3>
<p> To avoid clashes with future CSS features, the CSS2.1 specification
reserves a <a
href="http://www.w3.org/TR/CSS21/syndata.html#vendor-keywords">prefixed
syntax</a> for proprietary and experimental extensions to CSS.
<p> Prior to a specification reaching the Candidate Recommendation stage in
the W3C process, all implementations of a CSS feature are considered
experimental. The CSS Working Group recommends that implementations use a
vendor-prefixed syntax for such features, including those in W3C Working
Drafts. This avoids incompatibilities with future changes in the draft.
<h3 id=testing><span class=secno>5.5. </span> Non-Experimental
Implementations</h3>
<p> Once a specification reaches the Candidate Recommendation stage,
non-experimental implementations are possible, and implementors should
release an unprefixed implementation of any CR-level feature they can
demonstrate to be correctly implemented according to spec.
<p> To establish and maintain the interoperability of CSS across
implementations, the CSS Working Group requests that non-experimental CSS
renderers submit an implementation report (and, if necessary, the
testcases used for that implementation report) to the W3C before releasing
an unprefixed implementation of any CSS features. Testcases submitted to
W3C are subject to review and correction by the CSS Working Group.
<p> Further information on submitting testcases and implementation reports
can be found from on the CSS Working Group's website at <a
href="http://www.w3.org/Style/CSS/Test/">
http://www.w3.org/Style/CSS/Test/</a>. Questions should be directed to the
<a href="http://lists.w3.org/Archives/Public/public-css-testsuite">
public-css-testsuite@w3.org</a> mailing list.
<h3 id=cr-exit-criteria><span class=secno>5.6. </span> CR Exit Criteria</h3>
<p> For this specification to be advanced to Proposed Recommendation, there
must be at least two independent, interoperable implementations of each
feature. Each feature may be implemented by a different set of products,
there is no requirement that all features be implemented by a single
product. For the purposes of this criterion, we define the following
terms:
<dl>
<dt>independent
<dd> each implementation must be developed by a different party and cannot
share, reuse, or derive from code used by another qualifying
implementation. Sections of code that have no bearing on the
implementation of this specification are exempt from this requirement.
<dt>interoperable
<dd> passing the respective test case(s) in the official CSS test suite,
or, if the implementation is not a Web browser, an equivalent test. Every
relevant test in the test suite should have an equivalent test created if
such a user agent (UA) is to be used to claim interoperability. In
addition if such a UA is to be used to claim interoperability, then there
must one or more additional UAs which can also pass those equivalent
tests in the same way for the purpose of interoperability. The equivalent
tests must be made publicly available for the purposes of peer review.
<dt>implementation
<dd> a user agent which:
<ol class=inline>
<li>implements the specification.
<li>is available to the general public. The implementation may be a
shipping product or other publicly available version (i.e., beta
version, preview release, or “nightly build”). Non-shipping product
releases must have implemented the feature(s) for a period of at least
one month in order to demonstrate stability.
<li>is not experimental (i.e., a version specifically designed to pass
the test suite and is not intended for normal usage going forward).
</ol>
</dl>
<p> The specification will remain Candidate Recommendation for at least six
months.
<h2 class=no-num id=acknowledgments>Acknowledgments</h2>
<p> This specification is made possible by input from Stephen Zilles,
Alexandru Chiculita, Andrei Bucur, Mihnea Ovidenie, Peter Sorotokin,
Virgil Palanciuc, Alan Stearns, Arno Gourdol, Eugene Veselov, Arron
Eicholz, Alex Mogilevsky, Chris Jones, Marcus Mielke, and the CSS Working
Group members.
<h2 class=no-num id=references>References</h2>
<h3 class=no-num id=normative-references>Normative references</h3>
<!--begin-normative-->
<!-- Sorted by label -->
<dl class=bibliography>
<dt style="display: none"><!-- keeps the doc valid if the DL is empty -->
<!---->
<dt id=CSS21>[CSS21]
<dd>Bert Bos; et al. <a
href="http://www.w3.org/TR/2011/REC-CSS2-20110607"><cite>Cascading Style
Sheets Level 2 Revision 1 (CSS&#160;2.1) Specification.</cite></a> 7 June
2011. W3C Recommendation. URL: <a
href="http://www.w3.org/TR/2011/REC-CSS2-20110607">http://www.w3.org/TR/2011/REC-CSS2-20110607</a>
</dd>
<!---->
<dt id=RFC2119>[RFC2119]
<dd>S. Bradner. <a href="http://www.ietf.org/rfc/rfc2119.txt"><cite>Key
words for use in RFCs to Indicate Requirement Levels.</cite></a> Internet
RFC 2119. URL: <a
href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a>
</dd>
<!---->
</dl>
<!--end-normative-->
<h3 class=no-num id=other-references>Other references</h3>
<!--begin-informative-->
<!-- Sorted by label -->
<dl class=bibliography>
<dt style="display: none"><!-- keeps the doc valid if the DL is empty -->
<!---->
</dl>
<!--end-informative-->
<h2 class=no-num id=index>Index</h2>
<!--begin-index-->
<ul class=indexlist>
<li>authoring tool, <a href="#authoring-tool"
title="authoring tool"><strong>5.2.</strong></a>
<li>Content area, <a href="#content-area"
title="Content area"><strong>2.</strong></a>
<li>Exclusion area, <a href="#exclusion-area"
title="Exclusion area"><strong>2.</strong></a>
<li>Exclusion element, <a href="#exclusion-element"
title="Exclusion element"><strong>2.</strong></a>
<li>Flow Container, <a href="#flow-container"
title="Flow Container"><strong>4.</strong></a>
<li>outside-inside, <a href="#outside-and-inside"
title=outside-inside><strong>2.</strong></a>
<li>renderer, <a href="#renderer" title=renderer><strong>5.2.</strong></a>
<li>&lsquo;<a href="#shape-image-threshold"><code
class=property>shape-image-threshold</code></a>&rsquo;, <a
href="#shape-image-threshold"
title="'shape-image-threshold'"><strong>4.3.3.</strong></a>
<ul>
<li>&lsquo;<code class=css>&lt;alphavalue&gt;</code>&rsquo;, <a
href="#ltalphavaluegt"
title="'shape-image-threshold', '&lt;alphavalue&gt;'"><strong>4.3.3.</strong></a>
</ul>
<li>&lsquo;<a href="#shape-inside"><code
class=property>shape-inside</code></a>&rsquo;, <a href="#shape-inside"
title="'shape-inside'"><strong>4.3.2.</strong></a>
<ul>
<li>&lsquo;<code class=property>auto</code>&rsquo;, <a href="#auto1"
title="'shape-inside', 'auto'"><strong>4.3.2.</strong></a>
<li>&lsquo;<code class=property>outside-shape</code>&rsquo;, <a
href="#outside-shape"
title="'shape-inside', 'outside-shape'"><strong>4.3.2.</strong></a>
<li>&lsquo;<code class=css>&lt;shape&gt;</code>&rsquo;, <a
href="#ltshapegt0"
title="'shape-inside', '&lt;shape&gt;'"><strong>4.3.2.</strong></a>
<li>&lsquo;<code class=css>&lt;uri&gt;</code>&rsquo;, <a
href="#lturigt0"
title="'shape-inside', '&lt;uri&gt;'"><strong>4.3.2.</strong></a>
</ul>
<li>&lsquo;<a href="#shape-outside"><code
class=property>shape-outside</code></a>&rsquo;, <a href="#shape-outside"
title="'shape-outside'"><strong>4.3.1.</strong></a>
<ul>
<li>&lsquo;<code class=property>auto</code>&rsquo;, <a href="#auto0"
title="'shape-outside', 'auto'"><strong>4.3.1.</strong></a>
<li>&lsquo;<code class=css>&lt;shape&gt;</code>&rsquo;, <a
href="#ltshapegt"
title="'shape-outside', '&lt;shape&gt;'"><strong>4.3.1.</strong></a>
<li>&lsquo;<code class=css>&lt;uri&gt;</code>&rsquo;, <a href="#lturigt"
title="'shape-outside', '&lt;uri&gt;'"><strong>4.3.1.</strong></a>
</ul>
<li>style sheet
<ul>
<li>as conformance class, <a href="#style-sheet"
title="style sheet, as conformance class"><strong>5.2.</strong></a>
</ul>
<li>&lsquo;<a href="#wrap0"><code class=property>wrap</code></a>&rsquo;,
<a href="#wrap0" title="'wrap'"><strong>3.3.2.</strong></a>
<li>&lsquo;<a href="#wrap-flow"><code
class=property>wrap-flow</code></a>&rsquo;, <a href="#wrap-flow"
title="'wrap-flow'"><strong>3.1.1.</strong></a>
<ul>
<li>&lsquo;<code class=property>auto</code>&rsquo;, <a href="#auto"
title="'wrap-flow', 'auto'"><strong>3.1.1.</strong></a>
<li>&lsquo;<code class=property>both</code>&rsquo;, <a href="#both"
title="'wrap-flow', 'both'"><strong>3.1.1.</strong></a>
<li>&lsquo;<code class=property>clear</code>&rsquo;, <a href="#clear"
title="'wrap-flow', 'clear'"><strong>3.1.1.</strong></a>
<li>&lsquo;<code class=property>end</code>&rsquo;, <a href="#end"
title="'wrap-flow', 'end'"><strong>3.1.1.</strong></a>
<li>&lsquo;<code class=property>maximum</code>&rsquo;, <a
href="#maximum"
title="'wrap-flow', 'maximum'"><strong>3.1.1.</strong></a>
<li>&lsquo;<code class=property>start</code>&rsquo;, <a href="#start"
title="'wrap-flow', 'start'"><strong>3.1.1.</strong></a>
</ul>
<li>&lsquo;<a href="#wrap-margin"><code
class=property>wrap-margin</code></a>&rsquo;, <a href="#wrap-margin"
title="'wrap-margin'"><strong>3.2.1.</strong></a>
<li>&lsquo;<a href="#wrap-padding"><code
class=property>wrap-padding</code></a>&rsquo;, <a href="#wrap-padding"
title="'wrap-padding'"><strong>3.2.2.</strong></a>
<li>Wrapping context, <a href="#wrapping-context"
title="Wrapping context"><strong>2.</strong></a>
<li>&lsquo;<a href="#wrap-through"><code
class=property>wrap-through</code></a>&rsquo;, <a href="#wrap-through"
title="'wrap-through'"><strong>3.3.1.</strong></a>
<ul>
<li>&lsquo;<code class=property>none</code>&rsquo;, <a href="#none"
title="'wrap-through', 'none'"><strong>3.3.1.</strong></a>
<li>&lsquo;<a href="#wrap0"><code class=property>wrap</code></a>&rsquo;,
<a href="#wrap"
title="'wrap-through', 'wrap'"><strong>3.3.1.</strong></a>
</ul>
</ul>
<!--end-index-->
<h2 class=no-num id=property-index>Property index</h2>
<!--begin-properties-->
<table class=proptable>
<thead>
<tr>
<th>Property
<th>Values
<th>Initial
<th>Applies&nbsp;to
<th>Inh.
<th>Percentages
<th>Media
<tbody>
<tr>
<th><a class=property
href="#shape-image-threshold">shape-image-threshold</a>
<td>&lt;alphavalue&gt;
<td>0.5
<td>block-level elements
<td>no
<td>alpha channel of the image specified by &lt;uri&gt;
<td>visual
<tr>
<th><a class=property href="#shape-inside">shape-inside</a>
<td>outside-shape | auto | &lt;shape&gt; | &lt;uri&gt;
<td>outside-shape
<td>block-level elements
<td>no
<td>N/A
<td>visual
<tr>
<th><a class=property href="#shape-outside">shape-outside</a>
<td>auto | &lt;shape&gt; | &lt;uri&gt;
<td>auto
<td>block-level elements
<td>no
<td>N/A
<td>visual
<tr>
<th><a class=property href="#wrap0">wrap</a>
<td>&lt;wrap-flow&gt; || &lt;wrap-margin&gt; [ / &lt;wrap-padding&gt;]
<td>see individual properties
<td>block-level elements
<td>no
<td>N/A
<td>visual
<tr>
<th><a class=property href="#wrap-flow">wrap-flow</a>
<td>auto | both | start | end | maximum | clear
<td>auto
<td>block-level elements
<td>no
<td>N/A
<td>visual
<tr>
<th><a class=property href="#wrap-margin">wrap-margin</a>
<td>&lt;length&gt;
<td>0
<td>block-level elements
<td>no
<td>N/A
<td>visual
<tr>
<th><a class=property href="#wrap-padding">wrap-padding</a>
<td>&lt;length&gt;
<td>0
<td>block-level elements
<td>no
<td>N/A
<td>visual
<tr>
<th><a class=property href="#wrap-through">wrap-through</a>
<td>wrap | none
<td>wrap
<td>block-level elements
<td>no
<td>N/A
<td>visual
</table>
<!--end-properties-->
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