vertical.xml

GTK+-2.0源码之pango-1.15.6.tar.gz

<refentry id="pango-Vertical-Text">
<refmeta>
<refentrytitle id="top_of_page">Vertical Text</refentrytitle>
<manvolnum>3</manvolnum>
<refmiscinfo>PANGO Library</refmiscinfo>
</refmeta>

<refnamediv>
<refname>Vertical Text</refname>
<refpurpose>Laying text out in vertical directions</refpurpose>
<!--[<xref linkend="desc" endterm="desc.title"/>]-->
</refnamediv>

<refsynopsisdiv id="synopsis">
<title id="synopsis.title">Synopsis</title>

<synopsis>



enum        <link linkend="PangoGravity">PangoGravity</link>;
#define     <link linkend="PANGO-TYPE-GRAVITY:CAPS">PANGO_TYPE_GRAVITY</link>
enum        <link linkend="PangoGravityHint">PangoGravityHint</link>;
#define     <link linkend="PANGO-TYPE-GRAVITY-HINT:CAPS">PANGO_TYPE_GRAVITY_HINT</link>
#define     <link linkend="PANGO-GRAVITY-IS-VERTICAL:CAPS">PANGO_GRAVITY_IS_VERTICAL</link>       (gravity)
<link linkend="PangoGravity">PangoGravity</link> <link linkend="pango-gravity-get-for-matrix">pango_gravity_get_for_matrix</link>   (const <link linkend="PangoMatrix">PangoMatrix</link> *matrix);
<link linkend="PangoGravity">PangoGravity</link> <link linkend="pango-gravity-get-for-script">pango_gravity_get_for_script</link>   (<link linkend="PangoScript">PangoScript</link> script,
                                             <link linkend="PangoGravity">PangoGravity</link> base_gravity,
                                             <link linkend="PangoGravityHint">PangoGravityHint</link> hint);

</synopsis>
</refsynopsisdiv>









<refsect1 id="desc">
<title id="desc.title">Description</title>
<para>
Since 1.16, Pango is able to correctly lay vertical text out.  In fact, it can
set layouts of mixed vertical and non-vertical text.  This section describes
the types used for setting vertical text parameters.
</para>
</refsect1>

<refsect1 id="details">
<title id="details.title">Details</title>
<refsect2>
<title><anchor id="PangoGravity" role="enum" condition="since:1.16"/>enum PangoGravity</title>
<indexterm role="1.16"><primary>PangoGravity</primary></indexterm><programlisting>typedef enum {
  PANGO_GRAVITY_SOUTH,
  PANGO_GRAVITY_EAST,
  PANGO_GRAVITY_NORTH,
  PANGO_GRAVITY_WEST,
  PANGO_GRAVITY_AUTO
} PangoGravity;
</programlisting>
<para>
The <link linkend="PangoGravity"><type>PangoGravity</type></link> type represents the orientation of glyphs in a segment
of text.  This is useful when rendering vertical text layouts.  In
those situations, the layout is rotated using a non-identity PangoMatrix,
and then glyph orientation is controlled using <link linkend="PangoGravity"><type>PangoGravity</type></link>.
Not every value in this enumeration makes sense for every usage of
<link linkend="PangoGravity"><type>PangoGravity</type></link>; for example, <link linkend="PANGO-GRAVITY-AUTO:CAPS"><literal>PANGO_GRAVITY_AUTO</literal></link> only can be passed to
<link linkend="pango-context-set-base-gravity"><function>pango_context_set_base_gravity()</function></link> and can only be returned by
<link linkend="pango-context-get-base-gravity"><function>pango_context_get_base_gravity()</function></link>.
</para>
<para>
See also: <link linkend="PangoGravityHint"><type>PangoGravityHint</type></link></para>
<para>

</para><variablelist role="enum">
<varlistentry>
<term><anchor id="PANGO-GRAVITY-SOUTH:CAPS" role="constant"/><literal>PANGO_GRAVITY_SOUTH</literal></term>
<listitem><simpara> Glyphs stand upright (default)
</simpara></listitem>
</varlistentry>
<varlistentry>
<term><anchor id="PANGO-GRAVITY-EAST:CAPS" role="constant"/><literal>PANGO_GRAVITY_EAST</literal></term>
<listitem><simpara> Glyphs are rotated 90 degrees clockwise
</simpara></listitem>
</varlistentry>
<varlistentry>
<term><anchor id="PANGO-GRAVITY-NORTH:CAPS" role="constant"/><literal>PANGO_GRAVITY_NORTH</literal></term>
<listitem><simpara> Glyphs are upside-down
</simpara></listitem>
</varlistentry>
<varlistentry>
<term><anchor id="PANGO-GRAVITY-WEST:CAPS" role="constant"/><literal>PANGO_GRAVITY_WEST</literal></term>
<listitem><simpara> Glyphs are rotated 90 degrees counter-clockwise
</simpara></listitem>
</varlistentry>
<varlistentry>
<term><anchor id="PANGO-GRAVITY-AUTO:CAPS" role="constant"/><literal>PANGO_GRAVITY_AUTO</literal></term>
<listitem><simpara> Gravity is resolved from the context matrix
</simpara></listitem>
</varlistentry>
</variablelist><para>Since  1.16
</para></refsect2>
<refsect2>
<title><anchor id="PANGO-TYPE-GRAVITY:CAPS" role="macro"/>PANGO_TYPE_GRAVITY</title>
<indexterm><primary>PANGO_TYPE_GRAVITY</primary></indexterm><programlisting>#define PANGO_TYPE_GRAVITY (pango_gravity_get_type())
</programlisting>
<para>
The <link linkend="GObject"><type>GObject</type></link> type for <link linkend="PangoGravity"><type>PangoGravity</type></link>.
</para></refsect2>
<refsect2>
<title><anchor id="PangoGravityHint" role="enum" condition="since:1.16"/>enum PangoGravityHint</title>
<indexterm role="1.16"><primary>PangoGravityHint</primary></indexterm><programlisting>typedef enum {
  PANGO_GRAVITY_HINT_NATURAL,
  PANGO_GRAVITY_HINT_STRONG,
  PANGO_GRAVITY_HINT_LINE
} PangoGravityHint;
</programlisting>
<para>
The <link linkend="PangoGravityHint"><type>PangoGravityHint</type></link> defines how horizontal scripts should behave in a
vertical context.  That is, English excerpt in a vertical paragraph for
example.
</para>
<para>
See <link linkend="PangoGravity"><type>PangoGravity</type></link>.</para>
<para>

</para><variablelist role="enum">
<varlistentry>
<term><anchor id="PANGO-GRAVITY-HINT-NATURAL:CAPS" role="constant"/><literal>PANGO_GRAVITY_HINT_NATURAL</literal></term>
<listitem><simpara> scripts will take their natural gravity based
on the base gravity and the script.  This is the default.
</simpara></listitem>
</varlistentry>
<varlistentry>
<term><anchor id="PANGO-GRAVITY-HINT-STRONG:CAPS" role="constant"/><literal>PANGO_GRAVITY_HINT_STRONG</literal></term>
<listitem><simpara> always use the base gravity set, regardless of
the script.
</simpara></listitem>
</varlistentry>
<varlistentry>
<term><anchor id="PANGO-GRAVITY-HINT-LINE:CAPS" role="constant"/><literal>PANGO_GRAVITY_HINT_LINE</literal></term>
<listitem><simpara> for scripts not in their natural direction (eg.
Latin in East gravity), choose per-script gravity such that every script
respects the line progression.  This means, Latin and Arabic will take
opposite gravities and both flow top-to-bottom for example.
</simpara></listitem>
</varlistentry>
</variablelist><para>Since  1.16
</para></refsect2>
<refsect2>
<title><anchor id="PANGO-TYPE-GRAVITY-HINT:CAPS" role="macro"/>PANGO_TYPE_GRAVITY_HINT</title>
<indexterm><primary>PANGO_TYPE_GRAVITY_HINT</primary></indexterm><programlisting>#define PANGO_TYPE_GRAVITY_HINT (pango_gravity_hint_get_type())
</programlisting>
<para>
The <link linkend="GObject"><type>GObject</type></link> type for <link linkend="PangoGravity"><type>PangoGravity</type></link>.
</para></refsect2>
<refsect2>
<title><anchor id="PANGO-GRAVITY-IS-VERTICAL:CAPS" role="macro" condition="since:1.16"/>PANGO_GRAVITY_IS_VERTICAL()</title>
<indexterm role="1.16"><primary>PANGO_GRAVITY_IS_VERTICAL</primary></indexterm><programlisting>#define     PANGO_GRAVITY_IS_VERTICAL(gravity)</programlisting>
<para>
Whether a <link linkend="PangoGravity"><type>PangoGravity</type></link> represents vertical writing directions.</para>
<para>

</para><variablelist role="params">
<varlistentry><term><parameter>gravity</parameter>&nbsp;:</term>
<listitem><simpara> the <link linkend="PangoGravity"><type>PangoGravity</type></link> to check
</simpara></listitem></varlistentry>
</variablelist><para>Since  1.16
</para></refsect2>
<refsect2>
<title><anchor id="pango-gravity-get-for-matrix" role="function" condition="since:1.16"/>pango_gravity_get_for_matrix ()</title>
<indexterm role="1.16"><primary>pango_gravity_get_for_matrix</primary></indexterm><programlisting><link linkend="PangoGravity">PangoGravity</link> pango_gravity_get_for_matrix   (const <link linkend="PangoMatrix">PangoMatrix</link> *matrix);</programlisting>
<para>
Finds the gravity that best matches the rotation component
in a <link linkend="PangoMatrix"><type>PangoMatrix</type></link>.</para>
<para>

</para><variablelist role="params">
<varlistentry><term><parameter>matrix</parameter>&nbsp;:</term>
<listitem><simpara> a <link linkend="PangoMatrix"><type>PangoMatrix</type></link>
</simpara></listitem></varlistentry>
<varlistentry><term><emphasis>Returns</emphasis>&nbsp;:</term><listitem><simpara> the gravity of <parameter>matrix</parameter>, which will never be
<link linkend="PANGO-GRAVITY-AUTO:CAPS"><literal>PANGO_GRAVITY_AUTO</literal></link>, or <link linkend="PANGO-GRAVITY-SOUTH:CAPS"><literal>PANGO_GRAVITY_SOUTH</literal></link> if <parameter>matrix</parameter> is <link linkend="NULL:CAPS"><literal>NULL</literal></link>

</simpara></listitem></varlistentry>
</variablelist><para>Since  1.16
</para></refsect2>
<refsect2>
<title><anchor id="pango-gravity-get-for-script" role="function" condition="since:1.16"/>pango_gravity_get_for_script ()</title>
<indexterm role="1.16"><primary>pango_gravity_get_for_script</primary></indexterm><programlisting><link linkend="PangoGravity">PangoGravity</link> pango_gravity_get_for_script   (<link linkend="PangoScript">PangoScript</link> script,
                                             <link linkend="PangoGravity">PangoGravity</link> base_gravity,
                                             <link linkend="PangoGravityHint">PangoGravityHint</link> hint);</programlisting>
<para>
Based on the script, base gravity, and hint, returns actual gravity
to use in laying out a single <link linkend="PangoItem"><type>PangoItem</type></link>.
</para>
<para>
If <parameter>base_gravity</parameter> is <link linkend="PANGO-GRAVITY-AUTO:CAPS"><literal>PANGO_GRAVITY_AUTO</literal></link>, it is first replaced with the
preferred gravity of <parameter>script</parameter>.  To get the preferred gravity of a script,
pass <link linkend="PANGO-GRAVITY-AUTO:CAPS"><literal>PANGO_GRAVITY_AUTO</literal></link> and <link linkend="PANGO-GRAVITY-HINT-STRONG:CAPS"><literal>PANGO_GRAVITY_HINT_STRONG</literal></link> in.</para>
<para>

</para><variablelist role="params">
<varlistentry><term><parameter>script</parameter>&nbsp;:</term>
<listitem><simpara> <link linkend="PangoScript"><type>PangoScript</type></link> to query
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>base_gravity</parameter>&nbsp;:</term>
<listitem><simpara> base gravity of the paragraph
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>hint</parameter>&nbsp;:</term>
<listitem><simpara> orientation hint
</simpara></listitem></varlistentry>
<varlistentry><term><emphasis>Returns</emphasis>&nbsp;:</term><listitem><simpara> resolved gravity suitable to use for a run of text

</simpara></listitem></varlistentry>
</variablelist><para>Since  1.16
</para></refsect2>

</refsect1>




</refentry>