touchevents.html
author Rick Byers <rbyers@google.com>
Thu, 05 Jun 2014 23:24:51 -0400
changeset 224 bce3d93b8085
parent 223 df8e585dbc59
child 225 6892d44dee21
permissions -rw-r--r--
Change type of radiusX/radiusY to float to match proposed changes to screenX/screenY
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  </p>
  <h1 class="title p-name" id="title" property="dcterms:title">Touch Events Extensions</h1>
  
  <h2 property="dcterms:issued" datatype="xsd:dateTime" content="2013-10-31T04:00:00.000Z" id="w3c-working-group-note-31-october-2013"><abbr title="World Wide Web Consortium">W3C</abbr> Working Group Note <time class="dt-published" datetime="2013-10-31">31 October 2013</time></h2>
  <dl>
    
      <dt>This version:</dt>
      <dd><a class="u-url" href="http://www.w3.org/TR/2013/NOTE-touch-events-extensions-20131031/">http://www.w3.org/TR/2013/NOTE-touch-events-extensions-20131031/</a></dd>
      <dt>Latest published version:</dt>
      <dd><a href="http://www.w3.org/TR/touch-events-extensions/">http://www.w3.org/TR/touch-events-extensions/</a></dd>
    
    
      <dt>Latest editor's draft:</dt>
      <dd><a href="http://dvcs.w3.org/hg/webevents/raw-file/default/touchevents.html">http://dvcs.w3.org/hg/webevents/raw-file/default/touchevents.html</a></dd>
    
    
    
    
    
      <dt>Previous version:</dt>
      <dd>None</dd>
    
    
    <dt>Editors:</dt>
    <dd class="p-author h-card vcard" rel="bibo:editor" inlist=""><span typeof="foaf:Person"><a class="u-url url p-name fn" rel="foaf:homepage" property="foaf:name" content="Doug Schepers" href="http://schepers.cc/">Doug Schepers</a>, <a rel="foaf:workplaceHomepage" class="p-org org h-org h-card" href="http://w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a></span>
</dd>
<dd class="p-author h-card vcard" rel="bibo:editor" inlist=""><span typeof="foaf:Person"><a class="u-url url p-name fn" rel="foaf:homepage" property="foaf:name" content="Sangwhan Moon" href="http://sangwhan.com">Sangwhan Moon</a>, <a rel="foaf:workplaceHomepage" class="p-org org h-org h-card" href="http://www.opera.com/">Opera Software ASA</a></span>
</dd>
<dd class="p-author h-card vcard" rel="bibo:editor" inlist=""><span typeof="foaf:Person"><a class="u-url url p-name fn" rel="foaf:homepage" property="foaf:name" content="Matt Brubeck" href="http://limpet.net/mbrubeck/">Matt Brubeck</a>, <a rel="foaf:workplaceHomepage" class="p-org org h-org h-card" href="http://www.mozilla.org/">Mozilla</a></span>
</dd>

    
    
  </dl>
  
  
  
  
    
      <p class="copyright">
        <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> ©
        2013
        
        <a href="http://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup>
        (<a href="http://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>,
        <a href="http://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>,
        <a href="http://www.keio.ac.jp/">Keio</a>, <a href="http://ev.buaa.edu.cn/">Beihang</a>), 
        
        All Rights Reserved.
        
        <abbr title="World Wide Web Consortium">W3C</abbr> <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>,
        <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>
    
  
  <hr>
</div>
    <section id="abstract" class="introductory" property="dcterms:abstract" datatype="" typeof="bibo:Chapter" resource="#ref" rel="bibo:Chapter"><h2 aria-level="1" role="heading" id="h2_abstract">Abstract</h2>
        <p>This document defines <em>extensions</em> to the 
        <a href="http://www.w3.org/TR/touch-events/">Touch Events</a> specification
        that have been implemented by one or more browsers.</p>
	
        <p>We recommend that user agents implement the 
        <a href="http://www.w3.org/TR/touch-events/">Touch Events Recommendation</a>
        and/or the newer
        <a href="http://www.w3.org/TR/pointerevents/">Pointer Events</a>
        specification instead.</p>

        <p>This document is no longer being developed.</p>
    </section><section id="sotd" class="introductory" typeof="bibo:Chapter" resource="#ref" rel="bibo:Chapter"><h2 aria-level="1" role="heading" id="h2_sotd">Status of This Document</h2>
  
    
      
        <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 <abbr title="World Wide Web Consortium">W3C</abbr> publications and the latest revision
          of this technical report can be found in the <a href="http://www.w3.org/TR/"><abbr title="World Wide Web Consortium">W3C</abbr> technical reports
          index</a> at http://www.w3.org/TR/.</em>
        </p>

        
        <p>
	  This is the 31 October 2013 Working Group Note of "Touch Events Extensions". 

	  The W3C Membership and other interested parties are invited to review the 
	  document.

          If you wish to make comments regarding this document, please send them to 
          <a href="mailto:public-webevents@w3.org">public-webevents@w3.org</a> 
          (<a href="mailto:public-webevents-request@w3.org?subject=subscribe">subscribe</a>,
          <a href="http://lists.w3.org/Archives/Public/public-webevents/"> public archive</a>).
          
          All comments are welcome.</p>

        <p>
          This document was developed by the 
          <a href="http://www.w3.org/2010/webevents/">Web Events Working Group</a>.
	  This Working Group will not advance this Working Group Note to Recommendation Status.</p>
        
          <p>
            Publication as a Working Group Note does not imply endorsement by the <abbr title="World Wide Web Consortium">W3C</abbr> 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>
        
        
        <p>
          
            This document was produced by a group operating under the 
             
                <a id="sotd_patent" about="" rel="w3p:patentRules" href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February 2004 <abbr title="World Wide Web Consortium">W3C</abbr> Patent Policy</a>.
            
          
          
          
            
              <abbr title="World Wide Web Consortium">W3C</abbr> maintains a <a href="http://www.w3.org/2004/01/pp-impl/45559/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 <abbr title="World Wide Web Consortium">W3C</abbr> Patent Policy</a>.
          
          
        </p>
        
      
    
  
</section><section id="toc"><h2 class="introductory" aria-level="1" role="heading" id="h2_toc">Table of Contents</h2><ul class="toc" role="directory" id="respecContents"><li class="tocline"><a href="#introduction" class="tocxref"><span class="secno">1. </span>Introduction</a></li><li class="tocline"><a href="#touch-interface" class="tocxref"><span class="secno">2. </span><span class="formerLink"><code>Touch</code></span> Interface</a><ul class="toc"><li class="tocline"><a href="#attributes" class="tocxref"><span class="secno">2.1 </span>Attributes</a></li></ul></li><li class="tocline"><a href="#touchlist-interface" class="tocxref"><span class="secno">3. </span><span class="formerLink"><code>TouchList</code></span> Interface</a><ul class="toc"><li class="tocline"><a href="#methods" class="tocxref"><span class="secno">3.1 </span>Methods</a></li></ul></li><li class="tocline"><a href="#issues" class="tocxref"><span class="secno">4. </span>Issues</a></li><li class="tocline"><a href="#acknowledgements" class="tocxref"><span class="secno">A. </span>Acknowledgements</a></li><li class="tocline"><a href="#references" class="tocxref"><span class="secno">B. </span>References</a><ul class="toc"><li class="tocline"><a href="#normative-references" class="tocxref"><span class="secno">B.1 </span>Normative references</a></li></ul></li></ul></section>


    <section id="introduction" class="informative" typeof="bibo:Chapter" resource="#ref" rel="bibo:Chapter">
      <!--OddPage--><h2 aria-level="1" role="heading" id="h2_introduction"><span class="secno">1. </span>Introduction</h2><p><em>This section is non-normative.</em></p>

      <p>This document defines <em>extensions</em> to the 
       <a href="http://www.w3.org/TR/touch-events/">Touch Events</a> specification
       that have been implemented by one or more browsers.</p>
    </section>

    <section id="touch-interface">
      <!--OddPage--><h2 aria-level="1" role="heading" id="h2_touch-interface"><span class="secno">2. </span><a href="#idl-def-Touch" class="idlType"><code>Touch</code></a> Interface</h2>
      <p>
        This section defines <em>extensions</em> to the <a href="#idl-def-Touch" class="idlType"><code>Touch</code></a> interface
	defined in [<cite><a class="bibref" href="#bib-TOUCH-EVENTS">TOUCH-EVENTS</a></cite>].
      </p>

      <pre class="idl"><span class="idlInterface" id="idl-def-Touch">partial interface <span class="idlInterfaceID">Touch</span> {
<span class="idlAttribute">    readonly    attribute <span class="idlAttrType">float</span> <span class="idlAttrName"><a href="#widl-Touch-radiusX">radiusX</a></span>;</span>
<span class="idlAttribute">    readonly    attribute <span class="idlAttrType">float</span> <span class="idlAttrName"><a href="#widl-Touch-radiusY">radiusY</a></span>;</span>
<span class="idlAttribute">    readonly    attribute <span class="idlAttrType">float</span> <span class="idlAttrName"><a href="#widl-Touch-rotationAngle">rotationAngle</a></span>;</span>
<span class="idlAttribute">    readonly    attribute <span class="idlAttrType">float</span> <span class="idlAttrName"><a href="#widl-Touch-force">force</a></span>;</span>
};</span></pre><section id="attributes"><h3 aria-level="2" role="heading" id="h3_attributes"><span class="secno">2.1 </span>Attributes</h3><dl class="attributes"><dt id="widl-Touch-force"><code>force</code> of type <span class="idlAttrType">float</span>, readonly   </dt><dd>
          a relative value of pressure applied, in the range <code>0</code> to
          <code>1</code>, where <code>0</code> is no pressure, and
          <code>1</code> is the highest level of pressure the touch device is
          capable of sensing; <code>0</code> if no value is known.  In
          environments where force is known, the absolute pressure
          represented by the force attribute, and the sensitivity in
          levels of pressure, may vary.

          <div class="issue"><div class="issue-title" aria-level="3" role="heading" id="h_issue_1"><span>Issue 1</span></div><p class="" id="issue-inkml">
            <strong>Issue:</strong>
            Consider aligning with other "channels" and values from
            <a href="http://www.w3.org/TR/InkML/#channelContents">Ink Markup
            Language (InkML)</a>, in addition to force, e.g. adding
            angle, clientZ, rotation, etc.
          </p></div>
        </dd><dt id="widl-Touch-radiusX"><code>radiusX</code> of type <span class="idlAttrType">float</span>, readonly   </dt><dd>
          the radius of the ellipse which most closely circumscribes the
          touching area (e.g. finger, stylus) along the axis indicated by rotationAngle, in CSS pixels of
          the same scale as screenX; <code>1</code> if no value is
          known.  The value must be positive.
        </dd><dt id="widl-Touch-radiusY"><code>radiusY</code> of type <span class="idlAttrType">float</span>, readonly   </dt><dd>
          the radius of the ellipse which most closely circumscribes the
          touching area (e.g. finger, stylus) along the axis perpendicular to that indicated by rotationAngle, in CSS pixels of
          the same scale as screenY; <code>1</code> if no value is
          known.  The value must be positive.
        </dd><dt id="widl-Touch-rotationAngle"><code>rotationAngle</code> of type <span class="idlAttrType">float</span>, readonly   </dt><dd>
          <p>
            the angle (in degrees) that the ellipse described by <a>radiusX</a>
            and <a>radiusY</a> is rotated clockwise about its center;
            <code>0</code> if no value is known.  The value must be greater
            than or equal to <code>0</code> and less than <code>90</code>.
          </p>
          <p>
            If the ellipse described by <a>radiusX</a> and <a>radiusY</a> is
            circular, then <a>rotationAngle</a> has no effect.  The user agent
            may use <code>0</code> as the value in this case, or it may use any
            other value in the allowed range.  (For example, the user agent may
            use the <a>rotationAngle</a> value from the previous touch event,
            to avoid sudden changes.)
          </p>
        </dd></dl></section>
    </section>

    <section id="touchlist-interface">
      <!--OddPage--><h2 aria-level="1" role="heading" id="h2_touchlist-interface"><span class="secno">3. </span><a href="#idl-def-TouchList" class="idlType"><code>TouchList</code></a> Interface</h2>
      <p>
        This section defines an <em>extension</em> to the <a href="#idl-def-TouchList" class="idlType"><code>TouchList</code></a>
	interface defined in [<cite><a class="bibref" href="#bib-TOUCH-EVENTS">TOUCH-EVENTS</a></cite>].
      </p>

      <pre class="idl"><span class="idlInterface" id="idl-def-TouchList">partial interface <span class="idlInterfaceID">TouchList</span> {
<span class="idlMethod">    <span class="idlMethType"><a href="#idl-def-Touch" class="idlType"><code>Touch</code>?</a></span> <span class="idlMethName"><a href="#widl-TouchList-identifiedTouch-Touch-long-identifier">identifiedTouch</a></span> (<span class="idlParam"><span class="idlParamType">long</span> <span class="idlParamName">identifier</span></span>);</span>
};</span></pre><section id="methods"><h3 aria-level="2" role="heading" id="h3_methods"><span class="secno">3.1 </span>Methods</h3><dl class="methods"><dt id="widl-TouchList-identifiedTouch-Touch-long-identifier"><code>identifiedTouch</code></dt><dd>
          returns the first <a href="#idl-def-Touch" class="idlType"><code>Touch</code></a> item in the list whose identifier property matches the specified identifier or null if there is no match
        <table class="parameters"><tbody><tr><th>Parameter</th><th>Type</th><th>Nullable</th><th>Optional</th><th>Description</th></tr><tr><td class="prmName">identifier</td><td class="prmType"><code> <a>long</a></code></td><td class="prmNullFalse"><span role="img" aria-label="False">✘</span></td><td class="prmOptFalse"><span role="img" aria-label="False">✘</span></td><td class="prmDesc"></td></tr></tbody></table><div><em>Return type: </em><a href="#idl-def-Touch" class="idlType"><code> Touch</code></a>, <code>null</code></div></dd></dl></section>
    </section>

    <section id="issues" class="informative" typeof="bibo:Chapter" resource="#ref" rel="bibo:Chapter">
      <!--OddPage--><h2 aria-level="1" role="heading" id="h2_issues"><span class="secno">4. </span>Issues</h2><p><em>This section is non-normative.</em></p>
      <p>
        The working group maintains <a href="http://www.w3.org/2010/webevents/track/products/">a list of open issues for its documents</a>.
      </p>
    </section>

    <section class="appendix informative" id="acknowledgements">
      <!--OddPage--><h2 aria-level="1" role="heading" id="h2_acknowledgements"><span class="secno">A. </span>Acknowledgements</h2><p><em>This section is non-normative.</em></p>
      <p>
        Many thanks to the WebKit engineers for developing the model used as a
        basis for this document and to the members of the Web Events Working Group.
      </p>

    </section>
  

<section id="references" class="appendix" typeof="bibo:Chapter" resource="#ref" rel="bibo:Chapter"><!--OddPage--><h2 aria-level="1" role="heading" id="h2_references"><span class="secno">B. </span>References</h2><section id="normative-references" typeof="bibo:Chapter" resource="#ref" rel="bibo:Chapter"><h3 aria-level="2" role="heading" id="h3_normative-references"><span class="secno">B.1 </span>Normative references</h3><dl class="bibliography" about=""><dt id="bib-TOUCH-EVENTS">[TOUCH-EVENTS]</dt><dd rel="dcterms:requires">Doug Schepers; Sangwhan Moon; Matt Brubeck; Arthur Barstow. <a href="http://www.w3.org/TR/touch-events/"><cite>Touch Events</cite></a>. 10 October 2013. W3C Recommendation. URL: <a href="http://www.w3.org/TR/touch-events/">http://www.w3.org/TR/touch-events/</a>
</dd></dl></section></section></body></html>