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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html lang=en>
<head><meta content="text/html;charset=utf-8" http-equiv=Content-Type>
<title>CSS3 Module: Fonts</title>
<!--
FIXME when publishing: copy the current default.css and link to
"default.css" rather than "../default.css"
-->
<link href="../default.css" rel=stylesheet type="text/css">
<link href="http://www.w3.org/StyleSheets/TR/W3C-ED.css" rel=stylesheet
type="text/css">
<style type="text/css">
body {
padding: 2em 70px 2em 70px;
}
p + p, p.mtb {
margin-top: 0.8em;
text-indent: 0px;
}
#fontformats {
margin-left: 2em;
text-align: left;
}
#fontformats td {
padding-right: 2em;
}
dd {
margin-bottom: 1em;
}
pre {
font-size: 100%;
}
#authors dd {
margin-bottom: 0;
}
#fontstylematchingalg {
list-style-type: lower-alpha;
}
#fontmatchingalg ul, #fontmatchingalg ol {
margin-top: 0.8em;
}
#fontmatchingalg li + li {
margin-top: 0.8em;
}
div.example {
padding: 1em;
margin-top: 1em;
}
div.example + div.example {
margin-top: 2em;
}
div.figure {
page-break-inside: avoid;
}
</style>
<body>
<div class=head> <!--begin-logo-->
<p><a href="http://www.w3.org/"><img alt=W3C height=48
src="http://www.w3.org/Icons/w3c_home" width=72></a> <!--end-logo-->
<h1>CSS3 Module: Fonts</h1>
<h2 class="no-num no-toc" id=editors>Editor's Draft 19 January 2009</h2>
<dl id=authors>
<dt>This version:
<dd><a
href="http://dev.w3.org/csswg/css3-fonts/">http://dev.w3.org/csswg/css3-fonts/</a>
<dt>Latest version:
<dd><a
href="http://www.w3.org/TR/css3-fonts/">http://www.w3.org/TR/css3-fonts/</a>
<dt>Latest editor's draft:
<dd><a
href="http://dev.w3.org/csswg/css3-fonts/">http://dev.w3.org/csswg/css3-fonts/</a>
<dt>Previous version (CSS3 Fonts):
<dd><a
href="http://www.w3.org/TR/2002/WD-css3-fonts-20020802">http://www.w3.org/TR/2002/WD-css3-fonts-20020802</a>
<dt>Previous version (CSS3 Web Fonts):
<dd><a
href="http://www.w3.org/TR/2002/WD-css3-webfonts-20020802">http://www.w3.org/TR/2002/WD-css3-webfonts-20020802</a>
<dt>Editor:
<dd><a href="mailto:jdaggett@mozilla.com">John Daggett (Mozilla)</a>
</dl>
<!--begin-copyright-->
<p class=copyright><a
href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
rel=license>Copyright</a> © 2009 <a
href="http://www.w3.org/"><acronym title="World Wide Web
Consortium">W3C</acronym></a><sup>®</sup> (<a
href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute
of Technology">MIT</acronym></a>, <a
href="http://www.ercim.org/"><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
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>
<!--end-copyright-->
<hr title="Separator for header">
</div>
<!--
Note: this draft is still undergoing some major editing, so portions of
it may appear quite incoherent or inconsistent at times. Please wait a
month or so before sending out flames...
-->
<!--
To do:
- font matching examples
- polish font matching algorithm, deal with bolder/lighter matching
- clean up font-weight wording, better definition of bolder/lighter
- same for wider/narrower
- specifics of SVG font reference handling
- finish ex
9365
amples for unicode-range
- italic/oblique substitution issue
- font-size
- move font-variant into font rendering section
- font shorthand
- TrueType/OpenType nitty gritty
- make intro more concise and relevant to rest of the spec, point out specific general problems
- illustrations of localized bold, italic names?
-->
<h2 class="no-num no-toc" id=abstract>Abstract</h2>
<p>This CSS3 module describes how font properties are specified and how
font resources are loaded dynamically. The contents of this specification
are a consolidation of content previously divided into into CSS3 Fonts and
CSS3 Web Fonts.
<h2 class="no-num no-toc" id=status>Status of this document</h2>
<!--begin-status-->
<p>This is a public copy of the editors' draft. It is provided for
discussion only and may change at any moment. Its publication here does
not imply endorsement of its contents by W3C. Don't cite this document
other than as 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 “css3-fonts” in the subject, preferably like this:
“[<!---->css3-fonts<!---->] <em>…summary of
comment…</em>”
<p>This document was produced by the <a href="/Style/CSS/members">CSS
Working Group</a> (part of the <a href="/Style/">Style Activity</a>).
<p>This document was produced by a group operating under the <a
href="/Consortium/Patent-Policy-20040205/">5 February 2004 W3C Patent
Policy</a>. W3C maintains a <a href="/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="/Consortium/Patent-Policy-20040205/#def-essential">Essential
Claim(s)</a> must disclose the information in accordance with <a
href="/Consortium/Patent-Policy-20040205/#sec-Disclosure">section 6 of the
W3C Patent Policy</a>.</p>
<!--end-status-->
<h2 class="no-num no-toc" id=contents>Table of contents</h2>
<!--begin-toc-->
<ul class=toc>
<li><a href="#introduction"><span class=secno>1 </span>Introduction</a>
<li><a href="#typography"><span class=secno>2 </span>Typography
Background</a>
<li><a href="#font-properties"><span class=secno>3 </span>Font
properties</a>
<ul class=toc>
<li><a href="#font-family"><span class=secno>3.1 </span>Font family: the
‘<code class=property>font-family</code>’ property</a>
<ul class=toc>
<li><a href="#generic"><span class=secno>3.1.1 </span>Generic font
families</a>
</ul>
<li><a href="#font-weight"><span class=secno>3.2 </span>Font weight: the
‘<code class=property>font-weight</code>’ property</a>
<li><a href="#font-proportion"><span class=secno>3.3 </span>Font
proportion: the ‘<code class=property>font-stretch</code>’
property</a>
<li><a href="#font-style"><span class=secno>3.4 </span>Font style: the
‘<code class=property>font-style</code>’ property</a>
<li><a href="#small"><span class=secno>3.5 </span>Small caps: the
‘<code class=property>font-variant</code>’ property</a>
<li><a href="#font-size"><span class=secno>3.6 </span>Font size: the
‘<code class=property>font-size</code>’ property</a>
<li><a href="#relative"><span class=secno>3.7 </span>Relative sizing:
the ‘<code class=property>font-size-adjust</code>’
property</a>
<li><a href="#shorthand"><span class=secno>3.8 </span>Shorthand font
property: the ‘<code class=property>font</code>’
property</a>
</ul>
<li><a href="#font-resources"><span class=secno>4 </span>Font
resources</a>
<ul class=toc>
<li><a href="#the-font-face"><span class=secno>4.1 </span>The @font-face
rule</a>
<li><a href="#font-family0"><span class=secno>4.2 </span>Font family:
the ‘<code class=property>font-family</code>’
descriptor</a>
<li><a href="#font-reference"><span class=secno>4.3 </span>Font
reference: the ‘<code class=property>src</code>’
descriptor</a>
<li><a href="#font-property"><span class=secno>4.4 </span>Font property
descriptors: the ‘<code class=property>font-style</code>’,
‘<code class=property>font-weight</code>’, ‘<code
class=property>font-stretch</code>’ descriptors</a>
<li><a href="#character"><span class=secno>4.5 </span>Character range:
the ‘<code class=property>unicode-range</code>’
descriptor</a>
</ul>
<li><a href="#font-matching"><span class=secno>5 </span>Font matching
algorithm</a>
<ul class=toc>
<li><a href="#examples"><span class=secno>5.1 </span>Examples of font
matching</a>
</ul>
<li><a href="#font-rendering"><span class=secno>6 </span>Font rendering
properties</a>
<li class=no-num><a href="#appendix">Appendix A: Mapping CSS properties to
font features</a>
<li class=no-num><a href="#appendix0">Appendix B: Font licensing
issues</a>
<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">Normative</a>
<li class=no-num><a href="#informative">Informative</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=introduction><span class=secno>1 </span>Introduction</h2>
<p>Font properties in CSS determine which fonts are used when rendering
text. Fonts represent collections of letterforms, or glyphs, that uniquely
describe the visual appearance of the underlying characters. Fonts are
often grouped into font families that share a common aesthetic. In CSS,
font families are specified by name but a particular face within a family
is selected based on the value of other font properties. To specify text
in bold Helvetica, one could use:
<pre>
p { font-family: Helvetica; font-weight: bold; }
</pre>
<p>When an exact match doesn't exist for a particular combination of style
attributes, CSS defines a specific way in which another face is chosen.
Font properties are independent of each other, allowing text to be
rendered similarly even in environments where the set of available fonts
is different. In addition to the font properties defined in CSS2.1, CSS3
defines the @font-face rule which specifies font resources that can be
downloaded when needed, often referred to as "web fonts".
<h2 id=typography><span class=secno>2 </span>Typography Background</h2>
<!--
- Wide variation in character forms, glyphs
- Use of diacritics adds complications to even "simple" alphabets
- Examples from Czech, Slovak, African romanizations
- Vietnamese stacking example
- General use of ligatures
- Required for languages such as Arabic
- Problems with creating "universal fonts"
-->
<p><em>This section is included as background for some of the problems and
situations that are described in other sections. It should be viewed as
informative only.</em>
<p> Typographic traditions vary across the globe so there is no unique way
to classify all fonts across languages and cultures. For even common Latin
letters, wide variations are possible:
<div class=figure><img src=aaaaaa.png>
<p class=caption>One character, many glyph variations
</div>
<p>Differences in the anatomy of letterforms is one way to distinguish
fonts. For Latin fonts, flourishes at the ends of a character's main
strokes, or serifs, can distinguish a font from those without. Similar
comparisons exist in non-Latin fonts between fonts with tapered strokes
and those using primarily uniform strokes:
<div class=figure><img src=serifvssansserif.png>
<p class=caption>Letterforms with and without serifs
</div>
<div class=figure><img src=minchovsgothic.png>
<p class=caption>Similar groupings for Japanese typefaces
</div>
<p>Fonts contain letterforms and the data needed to map characters to these
letterforms. Often this may be a simple one-to-one mapping but more
complex mappings are also possible. The use of combining diacritic marks
creates many variations for an underlying letterform:
<div class=figure><img src=aaaaaa-diacritics.png>
<p class=caption>Variations with diacritic marks
</div>
<!-- Include stacking diacritics? Hmm, Vietnamese example? -->
<p>A sequence of characters can be represented by a single glyph known as a
ligature:
<div class=figure><img src=final-ligature.png>
<p class=caption>Ligature example
</div>
<p>Visual transformations based on textual context like this may be a
stylistic option for European langauges but are required to correctly
render languages like Arabic; the lam and alef characters below
<em>must</em> be combined when they exist in sequence:
<div class=figure><img src=lamaleflig.png>
<p class=caption>Required Arabic ligature
</div>
<p>The relative complexity of these shaping transformations requires
additional data within the font.
<p>Sets of font faces with various stylistic variations are often grouped
together into font families. In the simplest case a regular face is
supplemented with bold and italic faces but much more extensive groupings
are possible. Variations in the thickness of letterform strokes, or the
weight, or the overall proportions of the letterform, or the width, are
most common. In the example below, each letter uses a different font face
within the Univers font family. The width used increases from top to
bottom and the weight increases from left to right:
<div class=figure><img src=weightwidthvariations.png>
<p class=caption>Weight and width variations within a single font family
</div>
<p>Creating fonts that support multiple scripts is a difficult task;
designers need to understand the cultural traditions surronding the use of
type in different scripts and come up with letterforms that somehow share
a common theme. Many languages often share a common script and each of
these languages may have noticeable stylistic differences. The Arabic
script is shared by Persian and Urdu and Cyrillic is used with many
languages, not just Russian.
<p>Fonts provide a character map that details the set of characters for
they have glyphs. If a document contains characters not supported by a
specified font, a user agent may revert to a system font fallback
procedure to find glyphs to render these characters correctly. If no font
can be found, some form of "missing glyph" character is rendered by the
user agent. Often these are the result of authors failing to explicitly
indicate the encoding used by a document.
<h2 id=font-properties><span class=secno>3 </span>Font properties</h2>
<p>The particular font face used to render a character is determined by the
font family and other font properties that apply to a given element. This
structure allows settings to be varied independent of each other.</p>
<!-- prop: font-family -->
<h3 id=font-family><span class=secno>3.1 </span>Font family: the
‘<code class=property><a
href="#font-family2">font-family</a></code>’ property</h3>
<table class=propdef id=namefont-family>
<tbody>
<tr>
<td>Name:
<td><dfn id=font-family1>font-family</dfn>
<tr>
<td>Value:
<td>[[ <family-name> | <generic-family> ] [, <family-name>|
<generic-family>]* ] | inherit
<tr>
<td>Initial:
<td>depends on user agent
<tr>
<td>Applies to:
<td>all elements
<tr>
<td>Inherited:
<td>yes
<tr>
<td>Percentages:
<td>N/A
<tr>
<td>Media:
<td>visual
<tr>
<td>Computed value:
<td>as specified
</table>
<p>This property specifies a prioritized list of font family names or
generic family names. A user agent iterates through the list of family
names until it matches an available font that contains a glyph for the
character to be rendered. This allows for differences in available fonts
across across platforms and for differences in the range of characters
supported by individual fonts.
<p>A font family name only specifies a name given to a set of font faces,
it does not specify an individual face. Given the availability of the
fonts below, Futura would match but Futura Medium would not:
<div class=figure><img src=familyvsfacename.png>
<p class=caption>Family and individual face names
</div>
<p>Some font formats support the use of multiple family names for different
localizations. User agents should recognize any of these names independent
of the underlying platform localization, system API used or document
encoding:
<div class=figure><img src=localizedfamilynames.png>
<p class=caption>Localized family names
</div>
<p>Consider the example below:
<div class=example>
<pre>body {
font-family: Helvetica, Verdana, sans-serif;
}</pre>
</div>
<p>If Helvetica is available it will be used when rendering. If neither
Helvetica or Verdana is present, then the user agent defined sans serif
font will be used.
<p>There are two types of font family names:
<dl>
<dt><family-name>
<dd>The name of a font family of choice such as Helvetica or Verdana in
the previous example. Font family names containing more than one word
should be quoted. If quoting is omitted, whitespace characters before and
after the font family name are ignored and any sequence of whitespace
characters inside the font name is converted to a single space. Depending
upon the font format used, font family names may be case-sensitive.
<dt><generic-family>
<dd> The following generic family keywords are defined: ‘<code
class=property><a href="#serif">serif</a></code>’, ‘<code
class=property><a href="#sans-serif">sans-serif</a></code>’,
‘<code class=property><a href="#cursive">cursive</a></code>’,
‘<code class=property><a href="#fantasy">fantasy</a></code>’,
and ‘<code class=property><a
href="#monospace">monospace</a></code>’. These keywords can be used
as a general fallback mechanism when an author's desired font choices are
not available. As keywords, they should not be quoted. Authors are
encouraged to append a generic font family as a last alternative for
improved robustness.
</dl>
<h4 id=generic><span class=secno>3.1.1 </span>Generic font families</h4>
<p>All five generic font families are defined to exist in all CSS
implementations (they need not necessarily map to five distinct actual
fonts). User agents should provide reasonable default choices for the
generic font families, which express the characteristics of each family as
well as possible within the limits allowed by the underlying technology.
User agents are encouraged to allow users to select alternative choices
for the generic fonts.
<h5 class="no-num no-toc"> <span class=ind
D45
ex-def id=serif0 title="serif,
definition of"><a name=serif-def><dfn id=serif>serif</dfn></a></span></h5>
<p>Glyphs of serif fonts, as the term is used in CSS, have finishing
strokes, flared or tapering ends, or have actual serifed endings
(including slab serifs). Serif fonts are typically proportionately-spaced.
They often display a greater variation between thick and thin strokes than
fonts from the ‘<code class=property><a
href="#sans-serif">sans-serif</a></code>’ generic font family. CSS
uses the term ‘<code class=property><a
href="#serif">serif</a></code>’ to apply to a font for any script,
although other names may be more familiar for particular scripts, such as
Mincho (Japanese), Sung or Song (Chinese), Batang (Korean). Any font that
is so described may be used to represent the generic ‘<code
class=property><a href="#serif">serif</a></code>’ family.
<div class=figure><img src=serifexamples.png>
<p class=caption>Sample serif fonts
</div>
<h5 class="no-num no-toc"> <span class=index-def id=sans-serif0
title="sans-serif, definition of"> <a name=sans-serif-def><dfn
id=sans-serif>sans-serif</dfn></a></span></h5>
<p>Glyphs in sans-serif fonts, as the term is used in CSS, have stroke
endings that are plain -- without any flaring, cross stroke, or other
ornamentation. Sans-serif fonts are typically proportionately-spaced. They
often have little variation between thick and thin strokes, compared to
fonts from the ‘<code class=property><a
href="#serif">serif</a></code>’ family. CSS uses the term
‘<code class=property><a
href="#sans-serif">sans-serif</a></code>’ to apply to a font for any
script, although other names may be more familiar for particular scripts,
such as Gothic (Japanese), Kai (Chinese), or Gulim (Korean). Any font that
is so described may be used to represent the generic ‘<code
class=property><a href="#sans-serif">sans-serif</a></code>’ family.
<p class=issue>Kai for Chinese looks wrong, looks to be a serif-like face.
<div class=figure><img src=sansserifexamples.png>
<p class=caption>Sample sans-serif fonts
</div>
<h5 class="no-num no-toc"> <span class=index-def id=cursive0
title="cursive, definition of"> <a name=cursive-def><dfn
id=cursive>cursive</dfn></a></span></h5>
<p>Glyphs in cursive fonts generally have either joining strokes or other
cursive characteristics beyond those of italic typefaces. The glyphs are
partially or completely connected, and the result looks more like
handwritten pen or brush writing than printed letterwork. Some scripts,
such as Arabic, are almost always cursive. CSS uses the term ‘<code
class=property><a href="#cursive">cursive</a></code>’ to apply to a
font for any script, although other names such as Chancery, Brush, Swing
and Script are also used in font names.
<div class=figure><img src=cursiveexamples.png>
<p class=caption>Sample cursive fonts
</div>
<h5 class="no-num no-toc"> <span class=index-def id=fantasy0
title="fantasy, definition of"> <a name=fantasy-def><dfn
id=fantasy>fantasy</dfn></a></span></h5>
<p>Fantasy fonts are primarily decorative fonts that contain playful
representations of characters. These do not include Pi or Picture fonts
which do not represent actual characters.
<div class=figure><img src=fantasyexamples.png>
<p class=caption>Sample fantasy fonts
</div>
<h5 class="no-num no-toc"> <span class=index-def id=monospace0
title="monospace, definition of"> <a name=monospace-def><dfn
id=monospace>monospace</dfn></a></span></h5>
<p>The sole criterion of a monospace font is that all glyphs have the same
fixed width. This is often used to render samples of computer code.
<div class=figure><img src=monospaceexamples.png>
<p class=caption>Sample monospace fonts
</div>
<!-- prop: font-weight -->
<h3 id=font-weight><span class=secno>3.2 </span>Font weight: the
‘<code class=property><a
href="#font-weight1">font-weight</a></code>’ property</h3>
<table class=propdef id=namefont-weight>
<tbody>
<tr>
<td>Name:
<td><dfn id=font-weight0>font-weight</dfn>
<tr>
<td>Value:
<td>normal | bold | bolder | lighter | 100 | 200 | 300 | 400 | 500 | 600
| 700 | 800 | 900 | inherit
<tr>
<td>Initial:
<td>normal
<tr>
<td>Applies to:
<td>all elements
<tr>
<td>Inherited:
<td>yes
<tr>
<td>Percentages:
<td>N/A
<tr>
<td>Media:
<td>visual
<tr>
<td>Computed value:
<td>see description
</table>
<p>The <a class=noxref href="#font-weight"><span
class=property>‘<code
class=property>font-weight</code>’</span></a> property specifies
weight of glyphs in the font, their degree of blackness or stroke
thickness.
<p>Values have the following meanings:
<dl>
<dt>100 to 900
<dd>These values form an ordered sequence, where each number indicates a
weight that is at least as dark as its predecessor. These roughly
correspond to the commonly used weight names below:
</dl>
<ul>
<li>100 - Thin
<li>200 - Extra Light (Ultra Light)
<li>300 - Light
<li>400 - Normal
<li>500 - Medium
<li>600 - Semi Bold (Demi Bold)
<li>700 - Bold
<li>800 - Extra Bold (Ultra Bold)
<li>900 - Black (Heavy)
</ul>
<dl>
<dt><strong>normal</strong>
<dd>Same as ‘<code class=css>400</code>’.
<dt><strong>bold</strong>
<dd>Same as ‘<code class=css>700</code>’.
<dt><strong>bolder</strong>
<dd>Specifies the weight of the face bolder than the inherited value.
<dt><strong>lighter</strong>
<dd>Specifies the weight of the face lighter than the inherited value.
</dl>
<p>Font formats that use a scale other than a nine step scale should map
their scale onto the CSS scale so that 400 roughly corresponds with a face
that would be labeled as Regular, Book, Roman and 700 roughly matches a
face that would be labeled as Bold. Or weights may be inferred from the
style names, ones that correspond roughly with the scale above. The scale
is relative, so a face with a larger weight should never appear lighter.
If style names are used to infer weights, care should be taken to handle
common variations in different locales:
<p>Quite often there are only a few weights available for a particular font
family. When a weight is specified for which no face exists, a face with a
nearby weight is used. In general, bold weights map to faces with heavier
weights and light weights map to faces with lighter weights (see the font
matching section below for a precise definition). The examples here
illustrate which face is used for different weights, grey indicates a face
for that weight does not exist so a face with a nearby weight is used:
<div class=figure><img src=optimaweights.png>
<p class=caption>Weight mappings for a font family with 400, 700 and 900
weight faces
</div>
<div class=figure><img src=hiraginoweights.png>
<p class=caption>Weight mappings for a font family with 300 and 600 weight
faces
</div>
<p>Description of how bolder and lighter work. They are relative to an
inherited value and "accumulate". Child elements inherit the given weight
plus the accumulated relative bolder/lighter values.
<p>Although not well-loved by typographers, bold faces are often
synthesized by user agents for faces that lack actual bold faces. The use
of the lighter/bolder can lead to strange interactions with synthetic
bolding.</p>
<!-- prop: font-stretch -->
<h3 id=font-proportion><span class=secno>3.3 </span>Font proportion: the
‘<code class=property><a
href="#font-stretch0">font-stretch</a></code>’ property</h3>
<table class=propdef id=namefont-stretch>
<tbody>
<tr>
<td>Name:
<td><dfn id=font-stretch>font-stretch</dfn>
<tr>
<td>Value:
<td>normal | wider | narrower | ultra-condensed | extra-condensed |
condensed | semi-condensed | semi-expanded | expanded | extra-expanded
| ultra-expanded | inherit
<tr>
<td>Initial:
<td>normal
<tr>
<td>Applies to:
<td>all elements
<tr>
<td>Inherited:
<td>yes
<tr>
<td>Percentages:
<td>N/A
<tr>
<td>Media:
<td>visual
<tr>
<td>Computed value:
<td>as specified
</table>
<p>The <a class=noxref href="#font-stretch"><span
class=property>‘<code
class=property>font-stretch</code>’</span></a> property selects a
normal, condensed, or expanded face from a font family. Absolute keyword
values have the following ordering, from narrowest to widest:
<ul>
<li>Ultra Condensed
<li>Extra Condensed
<li>Condensed
<li>Semi Condensed
<li>Normal
<li>Semi Expanded
<li>Expanded
<li>Extra Expanded
<li>Ultra Expanded
</ul>
<p>The relative keyword ‘<code class=property>wider</code>’
sets the value to the next expanded value above the inherited value (while
not increasing it above ‘<code
class=property>ultra-expanded</code>’); the relative keyword
‘<code class=property>narrower</code>’ sets the value to the
next condensed value below the inherited value (while not decreasing it
below ‘<code class=property>ultra-condensed</code>’).
<p class=issue>Do we really need all these keywords?!? Would
ultra-expanded, expanded, normal, condensed, ultra-condensed suffice?
<p class=issue>What about synthesized condensed/expanded? What are the
"filling in the holes" rules, non-normal values map away from normal?</p>
<!-- prop: font-style -->
<h3 id=font-style><span class=secno>3.4 </span>Font style: the ‘<code
class=property><a href="#font-style1">font-style</a></code>’
property</h3>
<table class=propdef id=namefont-style>
<tbody>
<tr>
<td>Name:
<td><dfn id=font-style0>font-style</dfn>
<tr>
<td>Value:
<td>normal | italic | oblique | inherit
<tr>
<td>Initial:
<td>normal
<tr>
<td>Applies to:
<td>all elements
<tr>
<td>Inherited:
<td>yes
<tr>
<td>Percentages:
<td>N/A
<tr>
<td>Media:
<td>visual
<tr>
<td>Computed value:
<td>as specified
</table>
<p>The <a class=noxref href="#font-style"><span class=property>‘<code
class=property>font-style</code>’</span></a> property allows italic
or oblique faces to be selected. Italic forms are generally cursive in
nature while oblique faces are typically sloped versions of the regular
face. Oblique faces can be simulated by artificially sloping the glyphs of
the regular face. Compare the artificially sloped renderings of Palatino
‘<code class=property>a</code>’ and Baskerville ‘<code
class=property>N</code>’ in grey with the actual italic versions:
<div class=figure><img src=realvsfakeitalics.png>
<p class=caption>Artificial sloping versus real italics
</div>
<p>A value of ‘<code class=property>normal</code>’ selects a
face that is classified as ‘<code
class=property>normal</code>’, while ‘<code
class=property>oblique</code>’ selects a font that is labeled
‘<code class=property>oblique</code>’. A value of ‘<code
class=property>italic</code>’ selects a font that is labeled
‘<code class=property>italic</code>’, or, if that is not
available, one labeled ‘<code class=property>oblique</code>’.
If no italic or oblique faces is available, an oblique face can by
synthesized by rendering the normal face with a sloping transformation
applied.
<div class=figure>
<p class=caption>Common localizations of italic and oblique names
</div>
<p>Many scripts lack the tradition of mixing a cursive form within text
rendered with a normal face. Chinese, Japanese and Korean fonts almost
always lack italic or oblique faces. Fonts that support a mixture of
scripts will sometimes omit specific scripts such as Arabic from the set
of glyphs supported in the italic face. User agents should be careful
about making character map assumptions across faces.
<p class=issue>What is the existing behavior for oblique? Is it actually
<em>ever</em> relevant, i.e. is there a font that defines both italic and
oblique faces? Or is it effectively an alias for italic?</p>
<!-- prop: font-variant -->
<h3 id=small><span class=secno>3.5 </span>Small caps: the ‘<code
class=property><a href="#font-variant">font-variant</a></code>’
property</h3>
<table class=propdef id=namefont-variant>
<tbody>
<tr>
<td>Name:
<td><dfn id=font-variant>font-variant</dfn>
<tr>
<td>Value:
<td>normal | small-caps | inherit
<tr>
<td>Initial:
<td>normal
<tr>
<td>Applies to:
<td>all elements
<tr>
<td>Inherited:
<td>yes
<tr>
<td>Percentages:
<td>N/A
<tr>
<td>Media:
<td>visual
<tr>
<td>Computed value:
<td>as specified
</table>
<ul>
<li>small-caps
<li>used to select alternate glyphs if available in font
<li>can be simulated using sized versions of uppercase glyphs
</ul>
<p>In a small-caps font, the glyphs for lowercase letters look similar to
the uppercase ones, but in a smaller size and with slightly different
proportions. The <a class=noxref href="#font-variant"><span
class=property>‘<code