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index.html
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<!doctype html><html lang="en">
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
<meta content="width=device-width, initial-scale=1, shrink-to-fit=no" name="viewport">
<title>WebXR Expression Tracking - Level 1</title>
<meta content="UD" name="w3c-status">
<link href="https://www.w3.org/StyleSheets/TR/2021/W3C-UD" rel="stylesheet">
<link href="https://www.w3.org/2008/site/images/favicon.ico" rel="icon">
<meta content="Bikeshed version 26e85e599, updated Thu Dec 8 15:29:31 2022 -0800" name="generator">
<link href="https://cabanier.github.io/webxr-expression-tracking-1/" rel="canonical">
<link href="favicon-32x32.png" rel="icon" sizes="32x32" type="image/png">
<link href="favicon-96x96.png" rel="icon" sizes="96x96" type="image/png">
<style>
<style>
.non-normative::before {
content: "This section is non-normative.";
font-style: italic;
}
.tg {
border-collapse: collapse;
border-spacing: 0;
}
.tg th {
border-style: solid;
border-width: 1px;
background: #90b8de;
color: #fff;
font-family: sans-serif;
font-weight: bold;
border-color: grey;
}
.tg td {
padding: 4px 5px;
background-color: rgb(221, 238, 255);
font-family: monospace;
border-style: solid;
border-width: 1px;
border-color: grey;
overflow: hidden;
word-break: normal;
}
.unstable::before {
content: "This section is not stable";
display: block;
font-weight: bold;
text-align: right;
color: red;
}
.unstable {
border: thin solid pink;
border-radius: .5em;
padding: .5em;
margin: .5em calc(-0.5em - 1px);
background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' width='300' height='290'><text transform='rotate(-45)' text-anchor='middle' font-family='sans-serif' font-weight='bold' font-size='70' y='210' opacity='.1' fill='white'>Unstable</text></svg>");
background-repeat: repeat;
background-color: #282828;
}
@media (prefers-color-scheme: light) {
.unstable {
background-image: url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' width='300' height='290'><text transform='rotate(-45)' text-anchor='middle' font-family='sans-serif' font-weight='bold' font-size='70' y='210' opacity='.1'>Unstable</text></svg>");
background-color: #FFF4F4;
}
}
.unstable h3:first-of-type {
margin-top: 0.5rem;
}
.unstable.example:not(.no-marker)::before {
content: "Example " counter(example) " (Unstable)";
float: none;
}
</style>
<style>/* style-autolinks */
.css.css, .property.property, .descriptor.descriptor {
color: var(--a-normal-text);
font-size: inherit;
font-family: inherit;
}
.css::before, .property::before, .descriptor::before {
content: "‘";
}
.css::after, .property::after, .descriptor::after {
content: "’";
}
.property, .descriptor {
/* Don't wrap property and descriptor names */
white-space: nowrap;
}
.type { /* CSS value <type> */
font-style: italic;
}
pre .property::before, pre .property::after {
content: "";
}
[data-link-type="property"]::before,
[data-link-type="propdesc"]::before,
[data-link-type="descriptor"]::before,
[data-link-type="value"]::before,
[data-link-type="function"]::before,
[data-link-type="at-rule"]::before,
[data-link-type="selector"]::before,
[data-link-type="maybe"]::before {
content: "‘";
}
[data-link-type="property"]::after,
[data-link-type="propdesc"]::after,
[data-link-type="descriptor"]::after,
[data-link-type="value"]::after,
[data-link-type="function"]::after,
[data-link-type="at-rule"]::after,
[data-link-type="selector"]::after,
[data-link-type="maybe"]::after {
content: "’";
}
[data-link-type].production::before,
[data-link-type].production::after,
.prod [data-link-type]::before,
.prod [data-link-type]::after {
content: "";
}
[data-link-type=element],
[data-link-type=element-attr] {
font-family: Menlo, Consolas, "DejaVu Sans Mono", monospace;
font-size: .9em;
}
[data-link-type=element]::before { content: "<" }
[data-link-type=element]::after { content: ">" }
[data-link-type=biblio] {
white-space: pre;
}</style>
<style>/* style-colors */
/* Any --*-text not paired with a --*-bg is assumed to have a transparent bg */
:root {
color-scheme: light dark;
--text: black;
--bg: white;
--unofficial-watermark: url(https://www.w3.org/StyleSheets/TR/2016/logos/UD-watermark);
--logo-bg: #1a5e9a;
--logo-active-bg: #c00;
--logo-text: white;
--tocnav-normal-text: #707070;
--tocnav-normal-bg: var(--bg);
--tocnav-hover-text: var(--tocnav-normal-text);
--tocnav-hover-bg: #f8f8f8;
--tocnav-active-text: #c00;
--tocnav-active-bg: var(--tocnav-normal-bg);
--tocsidebar-text: var(--text);
--tocsidebar-bg: #f7f8f9;
--tocsidebar-shadow: rgba(0,0,0,.1);
--tocsidebar-heading-text: hsla(203,20%,40%,.7);
--toclink-text: var(--text);
--toclink-underline: #3980b5;
--toclink-visited-text: var(--toclink-text);
--toclink-visited-underline: #054572;
--heading-text: #005a9c;
--hr-text: var(--text);
--algo-border: #def;
--del-text: red;
--del-bg: transparent;
--ins-text: #080;
--ins-bg: transparent;
--a-normal-text: #034575;
--a-normal-underline: #bbb;
--a-visited-text: var(--a-normal-text);
--a-visited-underline: #707070;
--a-hover-bg: rgba(75%, 75%, 75%, .25);
--a-active-text: #c00;
--a-active-underline: #c00;
--blockquote-border: silver;
--blockquote-bg: transparent;
--blockquote-text: currentcolor;
--issue-border: #e05252;
--issue-bg: #fbe9e9;
--issue-text: var(--text);
--issueheading-text: #831616;
--example-border: #e0cb52;
--example-bg: #fcfaee;
--example-text: var(--text);
--exampleheading-text: #574b0f;
--note-border: #52e052;
--note-bg: #e9fbe9;
--note-text: var(--text);
--noteheading-text: hsl(120, 70%, 30%);
--notesummary-underline: silver;
--assertion-border: #aaa;
--assertion-bg: #eee;
--assertion-text: black;
--advisement-border: orange;
--advisement-bg: #fec;
--advisement-text: var(--text);
--advisementheading-text: #b35f00;
--warning-border: red;
--warning-bg: hsla(40,100%,50%,0.95);
--warning-text: var(--text);
--amendment-border: #330099;
--amendment-bg: #F5F0FF;
--amendment-text: var(--text);
--amendmentheading-text: #220066;
--def-border: #8ccbf2;
--def-bg: #def;
--def-text: var(--text);
--defrow-border: #bbd7e9;
--datacell-border: silver;
--indexinfo-text: #707070;
--indextable-hover-text: black;
--indextable-hover-bg: #f7f8f9;
--outdatedspec-bg: rgba(0, 0, 0, .5);
--outdatedspec-text: black;
--outdated-bg: maroon;
--outdated-text: white;
--outdated-shadow: red;
--editedrec-bg: darkorange;
}</style>
<style>/* style-counters */
body {
counter-reset: example figure issue;
}
.issue {
counter-increment: issue;
}
.issue:not(.no-marker)::before {
content: "Issue " counter(issue);
}
.example {
counter-increment: example;
}
.example:not(.no-marker)::before {
content: "Example " counter(example);
}
.invalid.example:not(.no-marker)::before,
.illegal.example:not(.no-marker)::before {
content: "Invalid Example" counter(example);
}
figcaption {
counter-increment: figure;
}
figcaption:not(.no-marker)::before {
content: "Figure " counter(figure) " ";
}</style>
<style>/* style-dfn-panel */
:root {
--dfnpanel-bg: #ddd;
--dfnpanel-text: var(--text);
}
.dfn-panel {
position: absolute;
z-index: 35;
height: auto;
width: -webkit-fit-content;
width: fit-content;
max-width: 300px;
max-height: 500px;
overflow: auto;
padding: 0.5em 0.75em;
font: small Helvetica Neue, sans-serif, Droid Sans Fallback;
background: var(--dfnpanel-bg);
color: var(--dfnpanel-text);
border: outset 0.2em;
}
.dfn-panel:not(.on) { display: none; }
.dfn-panel * { margin: 0; padding: 0; text-indent: 0; }
.dfn-panel > b { display: block; }
.dfn-panel a { color: var(--dfnpanel-text); }
.dfn-panel a:not(:hover) { text-decoration: none !important; border-bottom: none !important; }
.dfn-panel > b + b { margin-top: 0.25em; }
.dfn-panel ul { padding: 0; }
.dfn-panel li { list-style: inside; }
.dfn-panel.activated {
display: inline-block;
position: fixed;
left: .5em;
bottom: 2em;
margin: 0 auto;
max-width: calc(100vw - 1.5em - .4em - .5em);
max-height: 30vh;
}
.dfn-paneled { cursor: pointer; }
</style>
<style>/* style-issues */
a[href].issue-return {
float: right;
float: inline-end;
color: var(--issueheading-text);
font-weight: bold;
text-decoration: none;
}
</style>
<style>/* style-md-lists */
/* This is a weird hack for me not yet following the commonmark spec
regarding paragraph and lists. */
[data-md] > :first-child {
margin-top: 0;
}
[data-md] > :last-child {
margin-bottom: 0;
}</style>
<style>/* style-selflinks */
:root {
--selflink-text: white;
--selflink-bg: gray;
--selflink-hover-text: black;
}
.heading, .issue, .note, .example, li, dt {
position: relative;
}
a.self-link {
position: absolute;
top: 0;
left: calc(-1 * (3.5rem - 26px));
width: calc(3.5rem - 26px);
height: 2em;
text-align: center;
border: none;
transition: opacity .2s;
opacity: .5;
}
a.self-link:hover {
opacity: 1;
}
.heading > a.self-link {
font-size: 83%;
}
.example > a.self-link,
.note > a.self-link,
.issue > a.self-link {
/* These blocks are overflow:auto, so positioning outside
doesn't work. */
left: auto;
right: 0;
}
li > a.self-link {
left: calc(-1 * (3.5rem - 26px) - 2em);
}
dfn > a.self-link {
top: auto;
left: auto;
opacity: 0;
width: 1.5em;
height: 1.5em;
background: var(--selflink-bg);
color: var(--selflink-text);
font-style: normal;
transition: opacity .2s, background-color .2s, color .2s;
}
dfn:hover > a.self-link {
opacity: 1;
}
dfn > a.self-link:hover {
color: var(--selflink-hover-text);
}
a.self-link::before { content: "¶"; }
.heading > a.self-link::before { content: "§"; }
dfn > a.self-link::before { content: "#"; }
</style>
<style>/* style-syntax-highlighting */
pre.idl.highlight {
background: var(--borderedblock-bg, var(--def-bg));
}
code.highlight { padding: .1em; border-radius: .3em; }
pre.highlight, pre > code.highlight { display: block; padding: 1em; margin: .5em 0; overflow: auto; border-radius: 0; }
.highlight:not(.idl) { background: rgba(0, 0, 0, .03); }
c-[a] { color: #990055 } /* Keyword.Declaration */
c-[b] { color: #990055 } /* Keyword.Type */
c-[c] { color: #708090 } /* Comment */
c-[d] { color: #708090 } /* Comment.Multiline */
c-[e] { color: #0077aa } /* Name.Attribute */
c-[f] { color: #669900 } /* Name.Tag */
c-[g] { color: #222222 } /* Name.Variable */
c-[k] { color: #990055 } /* Keyword */
c-[l] { color: #000000 } /* Literal */
c-[m] { color: #000000 } /* Literal.Number */
c-[n] { color: #0077aa } /* Name */
c-[o] { color: #999999 } /* Operator */
c-[p] { color: #999999 } /* Punctuation */
c-[s] { color: #a67f59 } /* Literal.String */
c-[t] { color: #a67f59 } /* Literal.String.Single */
c-[u] { color: #a67f59 } /* Literal.String.Double */
c-[cp] { color: #708090 } /* Comment.Preproc */
c-[c1] { color: #708090 } /* Comment.Single */
c-[cs] { color: #708090 } /* Comment.Special */
c-[kc] { color: #990055 } /* Keyword.Constant */
c-[kn] { color: #990055 } /* Keyword.Namespace */
c-[kp] { color: #990055 } /* Keyword.Pseudo */
c-[kr] { color: #990055 } /* Keyword.Reserved */
c-[ld] { color: #000000 } /* Literal.Date */
c-[nc] { color: #0077aa } /* Name.Class */
c-[no] { color: #0077aa } /* Name.Constant */
c-[nd] { color: #0077aa } /* Name.Decorator */
c-[ni] { color: #0077aa } /* Name.Entity */
c-[ne] { color: #0077aa } /* Name.Exception */
c-[nf] { color: #0077aa } /* Name.Function */
c-[nl] { color: #0077aa } /* Name.Label */
c-[nn] { color: #0077aa } /* Name.Namespace */
c-[py] { color: #0077aa } /* Name.Property */
c-[ow] { color: #999999 } /* Operator.Word */
c-[mb] { color: #000000 } /* Literal.Number.Bin */
c-[mf] { color: #000000 } /* Literal.Number.Float */
c-[mh] { color: #000000 } /* Literal.Number.Hex */
c-[mi] { color: #000000 } /* Literal.Number.Integer */
c-[mo] { color: #000000 } /* Literal.Number.Oct */
c-[sb] { color: #a67f59 } /* Literal.String.Backtick */
c-[sc] { color: #a67f59 } /* Literal.String.Char */
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<h1 class="p-name no-ref" id="title">WebXR Expression Tracking - Level 1</h1>
<p id="w3c-state"><a href="https://www.w3.org/standards/types#UD">Unofficial Proposal Draft</a>, <time class="dt-updated" datetime="2022-12-13">13 December 2022</time></p>
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<summary>More details about this document</summary>
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<dl>
<dt>This version:
<dd><a class="u-url" href="https://cabanier.github.io/webxr-expression-tracking-1/">https://cabanier.github.io/webxr-expression-tracking-1/</a>
<dt>Issue Tracking:
<dd><a href="https://github.com/cabanier/webxr-expression-tracking-1/issues/">GitHub</a>
<dt class="editor">Editor:
<dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:[email protected]">Rik Cabanier</a> (<span class="p-org org">Meta</span>)
</dl>
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</details>
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<p class="copyright" data-fill-with="copyright"><a href="https://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 2022 <a href="https://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="https://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>, <a href="https://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="https://www.keio.ac.jp/">Keio</a>, <a href="https://ev.buaa.edu.cn/">Beihang</a>). W3C <a href="https://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="https://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document" rel="license">permissive document license</a> rules apply. </p>
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</div>
<div class="p-summary" data-fill-with="abstract">
<h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
<p>The WebXR Expression Tracking module expands the <a href="https://www.w3.org/TR/webxr/">WebXR Device API</a> with the functionality to track expressions.</p>
</div>
<h2 class="no-num no-toc no-ref heading settled" id="sotd"><span class="content">Status of this document</span></h2>
<div data-fill-with="status">
<p></p>
<p>This WebXR Module is designed as a module to be implemented in addition to <a href="https://www.w3.org/TR/webxr/">WebXR Device API</a>, and is originally included in WebXR Device API which was divided into core and modules.</p>
</div>
<div data-fill-with="at-risk"></div>
<nav data-fill-with="table-of-contents" id="toc">
<h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
<ol class="toc" role="directory">
<li><a href="#intro"><span class="secno">1</span> <span class="content">Introduction</span></a>
<li><a href="#initialization"><span class="secno">2</span> <span class="content">Initialization</span></a>
<li>
<a href="#expression-access"><span class="secno">3</span> <span class="content">Access to expressions</span></a>
<ol class="toc">
<li><a href="#expressions"><span class="secno">3.1</span> <span class="content">Expressions</span></a>
<li><a href="#expression-visuals"><span class="secno">3.2</span> <span class="content">Visual examples of expressions</span></a>
<li><a href="#xrexpressions-type"><span class="secno">3.3</span> <span class="content">XRExpressions</span></a>
</ol>
<li>
<a href="#frame-loop"><span class="secno">4</span> <span class="content">Frame Loop</span></a>
<ol class="toc">
<li><a href="#xrframe-interface"><span class="secno">4.1</span> <span class="content">XRFrame</span></a>
</ol>
<li><a href="#privacy-security"><span class="secno">5</span> <span class="content">Privacy & Security Considerations</span></a>
<li>
<a href="#w3c-conformance"><span class="secno"></span> <span class="content">Conformance</span></a>
<ol class="toc">
<li><a href="#w3c-conventions"><span class="secno"></span> <span class="content">Document conventions</span></a>
<li><a href="#w3c-conformant-algorithms"><span class="secno"></span> <span class="content">Conformant Algorithms</span></a>
</ol>
<li>
<a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
<ol class="toc">
<li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
<li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
</ol>
<li>
<a href="#references"><span class="secno"></span> <span class="content">References</span></a>
<ol class="toc">
<li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
<li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
</ol>
<li><a href="#idl-index"><span class="secno"></span> <span class="content">IDL Index</span></a>
</ol>
</nav>
<main>
<h2 class="heading settled" data-level="1" id="intro"><span class="secno">1. </span><span class="content">Introduction</span><a class="self-link" href="#intro"></a></h2>
<section class="non-normative"> This API exposes the expressions of the user’s face and the position of their eyes. This can be used to render a more immersive avatar. </section>
<h2 class="heading settled" data-level="2" id="initialization"><span class="secno">2. </span><span class="content">Initialization</span><a class="self-link" href="#initialization"></a></h2>
<p>If an application wants to get expressions during an immersive session, the session MUST be requested with an appropriate <a data-link-type="dfn" href="https://immersive-web.github.io/webxr/#feature-descriptor" id="ref-for-feature-descriptor">feature descriptor</a>. The string "<dfn class="dfn-paneled" data-dfn-for="feature descriptor" data-dfn-type="dfn" data-noexport id="feature-descriptor-expression-tracking">expression-tracking</dfn>" is introduced
by this module as a new valid <a data-link-type="dfn" href="https://immersive-web.github.io/webxr/#feature-descriptor" id="ref-for-feature-descriptor①">feature descriptor</a> for face expressions.</p>
<p>The "<a data-link-type="dfn" href="#feature-descriptor-expression-tracking" id="ref-for-feature-descriptor-expression-tracking">expression-tracking</a>" <a data-link-type="dfn" href="https://immersive-web.github.io/webxr/#feature-descriptor" id="ref-for-feature-descriptor②">feature descriptor</a> should only be granted for an <code class="idl"><a data-link-type="idl" href="https://immersive-web.github.io/webxr/#xrsession" id="ref-for-xrsession">XRSession</a></code> when its <a data-link-type="dfn" href="https://immersive-web.github.io/webxr/#xrsession-xr-device" id="ref-for-xrsession-xr-device">XR device</a> has sensor data to support reporting of expressions.</p>
<h2 class="heading settled" data-level="3" id="expression-access"><span class="secno">3. </span><span class="content">Access to expressions</span><a class="self-link" href="#expression-access"></a></h2>
<h3 class="heading settled" data-level="3.1" id="expressions"><span class="secno">3.1. </span><span class="content">Expressions</span><a class="self-link" href="#expressions"></a></h3>
<p>An expression MUST be one of the <code class="idl"><a data-link-type="idl" href="#enumdef-xrexpression" id="ref-for-enumdef-xrexpression">XRExpression</a></code> types.
A user agent MAY support a subset of <code class="idl"><a data-link-type="idl" href="#enumdef-xrexpression" id="ref-for-enumdef-xrexpression①">XRExpression</a></code> types and this subset is allowed to change during an <code class="idl"><a data-link-type="idl" href="https://immersive-web.github.io/webxr/#xrsession" id="ref-for-xrsession①">XRSession</a></code></p>
<p>Following is the <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="list-of-expressions">list of expressions</dfn> and their order:</p>
<pre class="idl highlight def"><c- b>enum</c-> <dfn class="dfn-paneled idl-code" data-dfn-type="enum" data-export id="enumdef-xrexpression"><code><c- g>XRExpression</c-></code></dfn> {
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-brow_lowerer_left"><code><c- s>"brow_lowerer_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-brow_lowerer_right"><code><c- s>"brow_lowerer_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-cheek_puff_left"><code><c- s>"cheek_puff_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-cheek_puff_right"><code><c- s>"cheek_puff_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-cheek_raiser_left"><code><c- s>"cheek_raiser_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-cheek_raiser_right"><code><c- s>"cheek_raiser_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-cheek_suck_left"><code><c- s>"cheek_suck_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-cheek_suck_right"><code><c- s>"cheek_suck_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-chin_raiser_bottom"><code><c- s>"chin_raiser_bottom"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-chin_raiser_top"><code><c- s>"chin_raiser_top"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-dimpler_left"><code><c- s>"dimpler_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-dimpler_right"><code><c- s>"dimpler_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_closed_left"><code><c- s>"eyes_closed_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_closed_right"><code><c- s>"eyes_closed_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_look_down_left"><code><c- s>"eyes_look_down_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_look_down_right"><code><c- s>"eyes_look_down_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_look_left_left"><code><c- s>"eyes_look_left_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_look_left_right"><code><c- s>"eyes_look_left_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_look_right_left"><code><c- s>"eyes_look_right_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_look_right_right"><code><c- s>"eyes_look_right_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_look_up_left"><code><c- s>"eyes_look_up_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-eyes_look_up_right"><code><c- s>"eyes_look_up_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-inner_brow_raiser_left"><code><c- s>"inner_brow_raiser_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-inner_brow_raiser_right"><code><c- s>"inner_brow_raiser_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-jaw_drop"><code><c- s>"jaw_drop"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-jaw_sideways_left"><code><c- s>"jaw_sideways_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-jaw_sideways_right"><code><c- s>"jaw_sideways_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-jaw_thrust"><code><c- s>"jaw_thrust"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lid_tightener_left"><code><c- s>"lid_tightener_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lid_tightener_right"><code><c- s>"lid_tightener_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_corner_depressor_left"><code><c- s>"lip_corner_depressor_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_corner_depressor_right"><code><c- s>"lip_corner_depressor_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_corner_puller_left"><code><c- s>"lip_corner_puller_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_corner_puller_right"><code><c- s>"lip_corner_puller_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_funneler_left_bottom"><code><c- s>"lip_funneler_left_bottom"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_funneler_left_top"><code><c- s>"lip_funneler_left_top"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_funneler_right_bottom"><code><c- s>"lip_funneler_right_bottom"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_funneler_right_top"><code><c- s>"lip_funneler_right_top"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_pressor_left"><code><c- s>"lip_pressor_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_pressor_right"><code><c- s>"lip_pressor_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_pucker_left"><code><c- s>"lip_pucker_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_pucker_right"><code><c- s>"lip_pucker_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_stretcher_left"><code><c- s>"lip_stretcher_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_stretcher_right"><code><c- s>"lip_stretcher_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_suck_left_bottom"><code><c- s>"lip_suck_left_bottom"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_suck_left_top"><code><c- s>"lip_suck_left_top"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_suck_right_bottom"><code><c- s>"lip_suck_right_bottom"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_suck_right_top"><code><c- s>"lip_suck_right_top"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_tightener_left"><code><c- s>"lip_tightener_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lip_tightener_right"><code><c- s>"lip_tightener_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lips_toward"><code><c- s>"lips_toward"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lower_lip_depressor_left"><code><c- s>"lower_lip_depressor_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-lower_lip_depressor_right"><code><c- s>"lower_lip_depressor_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-mouth_left"><code><c- s>"mouth_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-mouth_right"><code><c- s>"mouth_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-nose_wrinkler_left"><code><c- s>"nose_wrinkler_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-nose_wrinkler_right"><code><c- s>"nose_wrinkler_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-outer_brow_raiser_left"><code><c- s>"outer_brow_raiser_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-outer_brow_raiser_right"><code><c- s>"outer_brow_raiser_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-upper_lid_raiser_left"><code><c- s>"upper_lid_raiser_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-upper_lid_raiser_right"><code><c- s>"upper_lid_raiser_right"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-upper_lip_raiser_left"><code><c- s>"upper_lip_raiser_left"</c-></code></dfn>,
<dfn class="dfn-paneled idl-code" data-dfn-for="XRExpression" data-dfn-type="enum-value" data-export id="dom-xrexpression-upper_lip_raiser_right"><code><c- s>"upper_lip_raiser_right"</c-></code></dfn>
};
</pre>
<h3 class="heading settled" data-level="3.2" id="expression-visuals"><span class="secno">3.2. </span><span class="content">Visual examples of expressions</span><a class="self-link" href="#expression-visuals"></a></h3>
<section class="non-normative">
<figure>
<img src="media/neutral.png">
<figcaption align="center"><b>neutral</b> </figcaption>
</figure>
<figure>
<img src="media/brow_lowerer_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-brow_lowerer_left" id="ref-for-dom-xrexpression-brow_lowerer_left">brow_lowerer_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/brow_lowerer_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-brow_lowerer_right" id="ref-for-dom-xrexpression-brow_lowerer_right">brow_lowerer_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/cheek_puff_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-cheek_puff_left" id="ref-for-dom-xrexpression-cheek_puff_left">cheek_puff_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/cheek_puff_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-cheek_puff_right" id="ref-for-dom-xrexpression-cheek_puff_right">cheek_puff_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/cheek_raiser_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-cheek_raiser_left" id="ref-for-dom-xrexpression-cheek_raiser_left">cheek_raiser_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/cheek_raiser_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-cheek_raiser_right" id="ref-for-dom-xrexpression-cheek_raiser_right">cheek_raiser_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/cheek_suck_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-cheek_suck_left" id="ref-for-dom-xrexpression-cheek_suck_left">cheek_suck_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/cheek_suck_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-cheek_suck_right" id="ref-for-dom-xrexpression-cheek_suck_right">cheek_suck_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/chin_raiser_bottom.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-chin_raiser_bottom" id="ref-for-dom-xrexpression-chin_raiser_bottom">chin_raiser_bottom</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/chin_raiser_top.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-chin_raiser_top" id="ref-for-dom-xrexpression-chin_raiser_top">chin_raiser_top</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/dimpler_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-dimpler_left" id="ref-for-dom-xrexpression-dimpler_left">dimpler_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/dimpler_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-dimpler_right" id="ref-for-dom-xrexpression-dimpler_right">dimpler_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_closed_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_closed_left" id="ref-for-dom-xrexpression-eyes_closed_left">eyes_closed_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_closed_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_closed_right" id="ref-for-dom-xrexpression-eyes_closed_right">eyes_closed_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_look_down_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_look_down_left" id="ref-for-dom-xrexpression-eyes_look_down_left">eyes_look_down_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_look_down_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_look_down_right" id="ref-for-dom-xrexpression-eyes_look_down_right">eyes_look_down_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_look_left_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_look_left_left" id="ref-for-dom-xrexpression-eyes_look_left_left">eyes_look_left_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_look_left_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_look_left_right" id="ref-for-dom-xrexpression-eyes_look_left_right">eyes_look_left_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_look_right_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_look_right_left" id="ref-for-dom-xrexpression-eyes_look_right_left">eyes_look_right_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_look_right_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_look_right_right" id="ref-for-dom-xrexpression-eyes_look_right_right">eyes_look_right_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_look_up_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_look_up_left" id="ref-for-dom-xrexpression-eyes_look_up_left">eyes_look_up_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/eyes_look_up_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-eyes_look_up_right" id="ref-for-dom-xrexpression-eyes_look_up_right">eyes_look_up_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/inner_brow_raiser_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-inner_brow_raiser_left" id="ref-for-dom-xrexpression-inner_brow_raiser_left">inner_brow_raiser_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/inner_brow_raiser_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-inner_brow_raiser_right" id="ref-for-dom-xrexpression-inner_brow_raiser_right">inner_brow_raiser_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/jaw_drop.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-jaw_drop" id="ref-for-dom-xrexpression-jaw_drop">jaw_drop</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/jaw_sideways_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-jaw_sideways_left" id="ref-for-dom-xrexpression-jaw_sideways_left">jaw_sideways_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/jaw_sideways_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-jaw_sideways_right" id="ref-for-dom-xrexpression-jaw_sideways_right">jaw_sideways_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/jaw_thrust.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-jaw_thrust" id="ref-for-dom-xrexpression-jaw_thrust">jaw_thrust</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lid_tightener_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lid_tightener_left" id="ref-for-dom-xrexpression-lid_tightener_left">lid_tightener_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lid_tightener_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lid_tightener_right" id="ref-for-dom-xrexpression-lid_tightener_right">lid_tightener_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_corner_depressor_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_corner_depressor_left" id="ref-for-dom-xrexpression-lip_corner_depressor_left">lip_corner_depressor_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_corner_depressor_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_corner_depressor_right" id="ref-for-dom-xrexpression-lip_corner_depressor_right">lip_corner_depressor_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_corner_puller_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_corner_puller_left" id="ref-for-dom-xrexpression-lip_corner_puller_left">lip_corner_puller_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_corner_puller_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_corner_puller_right" id="ref-for-dom-xrexpression-lip_corner_puller_right">lip_corner_puller_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_funneler_left_bottom.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_funneler_left_bottom" id="ref-for-dom-xrexpression-lip_funneler_left_bottom">lip_funneler_left_bottom</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_funneler_left_top.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_funneler_left_top" id="ref-for-dom-xrexpression-lip_funneler_left_top">lip_funneler_left_top</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_funneler_right_bottom.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_funneler_right_bottom" id="ref-for-dom-xrexpression-lip_funneler_right_bottom">lip_funneler_right_bottom</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_funneler_right_top.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_funneler_right_top" id="ref-for-dom-xrexpression-lip_funneler_right_top">lip_funneler_right_top</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_pressor_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_pressor_left" id="ref-for-dom-xrexpression-lip_pressor_left">lip_pressor_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_pressor_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_pressor_right" id="ref-for-dom-xrexpression-lip_pressor_right">lip_pressor_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_pucker_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_pucker_left" id="ref-for-dom-xrexpression-lip_pucker_left">lip_pucker_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_pucker_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_pucker_right" id="ref-for-dom-xrexpression-lip_pucker_right">lip_pucker_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_stretcher_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_stretcher_left" id="ref-for-dom-xrexpression-lip_stretcher_left">lip_stretcher_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_stretcher_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_stretcher_right" id="ref-for-dom-xrexpression-lip_stretcher_right">lip_stretcher_right</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_suck_left_bottom.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_suck_left_bottom" id="ref-for-dom-xrexpression-lip_suck_left_bottom">lip_suck_left_bottom</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_suck_left_top.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_suck_left_top" id="ref-for-dom-xrexpression-lip_suck_left_top">lip_suck_left_top</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_suck_right_bottom.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_suck_right_bottom" id="ref-for-dom-xrexpression-lip_suck_right_bottom">lip_suck_right_bottom</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_suck_right_top.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_suck_right_top" id="ref-for-dom-xrexpression-lip_suck_right_top">lip_suck_right_top</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_tightener_left.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_tightener_left" id="ref-for-dom-xrexpression-lip_tightener_left">lip_tightener_left</a></code></b> </figcaption>
</figure>
<figure>
<img src="media/lip_tightener_right.png">
<figcaption align="center"><b><code class="idl"><a data-link-type="idl" href="#dom-xrexpression-lip_tightener_right" id="ref-for-dom-xrexpression-lip_tightener_right">lip_tightener_right</a></code></b> </figcaption>
</figure>