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1 files changed, 26 insertions, 52 deletions
diff --git a/Build/source/libs/freetype2/freetype-src/docs/reference/ft2-tt_driver.html b/Build/source/libs/freetype2/freetype-src/docs/reference/ft2-tt_driver.html
index aea3aa720a1..b3b905a41ef 100644
--- a/Build/source/libs/freetype2/freetype-src/docs/reference/ft2-tt_driver.html
+++ b/Build/source/libs/freetype2/freetype-src/docs/reference/ft2-tt_driver.html
@@ -3,7 +3,7 @@
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
-<title>FreeType-2.7.1 API Reference</title>
+<title>FreeType-2.8 API Reference</title>
<style type="text/css">
a:link { color: #0000EF; }
a:visited { color: #51188E; }
@@ -100,7 +100,7 @@
<body>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table>
-<h1>FreeType-2.7.1 API Reference</h1>
+<h1>FreeType-2.8 API Reference</h1>
<h1 id="tt_driver">The TrueType driver</h1>
<h2>Synopsis</h2>
@@ -122,61 +122,35 @@
<p>One of the earliest challenges with ClearType was allowing the implementation in GDI to be selected without requiring all UI and documents to reflow. To address this, a compatible method of rendering ClearType was added where the font hints are executed once to determine the width in bi-level rendering, and then re-run in ClearType, with the difference in widths being absorbed in the font hints for ClearType (mostly in the white space of hints); see <a href="http://www.beatstamm.com/typography/RTRCh4.htm#Sec20">http://www.beatstamm.com/typography/RTRCh4.htm#Sec20</a>. Somewhat by definition, compatible width ClearType allows for non-linear widths, but only when the bi-level version has non-linear widths.</p>
<p><i>ClearType</i> <i>Subpixel</i> <i>Positioning</i></p>
<p>One of the nice benefits of ClearType is the ability to more crisply display fractional widths; unfortunately, the GDI model of integer bitmaps did not support this. However, the WPF and Direct Write frameworks do support fractional widths. DWrite calls this &lsquo;natural mode&rsquo;, not to be confused with GDI's &lsquo;natural widths&rsquo;. Subpixel positioning, in the current implementation of Direct Write, unfortunately does not support hinted advance widths, see <a href="http://www.beatstamm.com/typography/RTRCh4.htm#Sec22">http://www.beatstamm.com/typography/RTRCh4.htm#Sec22</a>. Note that the TrueType interpreter fully allows the advance width to be adjusted in this mode, just the DWrite client will ignore those changes.</p>
-<p><i>ClearType</i> <i>Backwards</i> <i>Compatibility</i></p>
-<p>This is a set of exceptions made in the TrueType interpreter to minimize hinting techniques that were problematic with the extra resolution of ClearType; see <a href="http://www.beatstamm.com/typography/RTRCh4.htm#Sec1">http://www.beatstamm.com/typography/RTRCh4.htm#Sec1</a> and <a href="http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx">http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx</a>. This technique is not to be confused with ClearType compatible widths. ClearType backwards compatibility has no direct impact on changing advance widths, but there might be an indirect impact on disabling some deltas. This could be worked around in backwards compatibility mode.</p>
+<p><i>ClearType</i> <i>Backward</i> <i>Compatibility</i></p>
+<p>This is a set of exceptions made in the TrueType interpreter to minimize hinting techniques that were problematic with the extra resolution of ClearType; see <a href="http://www.beatstamm.com/typography/RTRCh4.htm#Sec1">http://www.beatstamm.com/typography/RTRCh4.htm#Sec1</a> and <a href="http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx">http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx</a>. This technique is not to be confused with ClearType compatible widths. ClearType backward compatibility has no direct impact on changing advance widths, but there might be an indirect impact on disabling some deltas. This could be worked around in backward compatibility mode.</p>
<p><i>Native</i> <i>ClearType</i> <i>Mode</i></p>
<p>(Not to be confused with &lsquo;natural widths&rsquo;.) This mode removes all the exceptions in the TrueType interpreter when running with ClearType. Any issues on widths would still apply, though.</p>
<div class="section">
<h3 id="interpreter-version">interpreter-version</h3>
-<p>Defined in FT_TRUETYPE_DRIVER_H (freetype/ftttdrv.h).</p>
-<pre>
- * Currently, three versions are available, two representing the
- * bytecode interpreter with subpixel hinting support (old `Infinality'
- * code and new stripped-down and higher performance `minimal' code) and
- * one without, respectively. The default is subpixel support if
- * TT_CONFIG_OPTION_SUBPIXEL_HINTING is defined, and no subpixel support
- * otherwise (since it isn't available then).
- *
- * If subpixel hinting is on, many TrueType bytecode instructions behave
- * differently compared to B/W or grayscale rendering (except if `native
- * ClearType' is selected by the font). Microsoft's main idea is to
- * render at a much increased horizontal resolution, then sampling down
- * the created output to subpixel precision. However, many older fonts
- * are not suited to this and must be specially taken care of by
- * applying (hardcoded) tweaks in Microsoft's interpreter.
- *
- * Details on subpixel hinting and some of the necessary tweaks can be
- * found in Greg Hitchcock's whitepaper at
- * `http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx'.
- * Note that FreeType currently doesn't really `subpixel hint' (6x1, 6x2,
- * or 6x5 supersampling) like discussed in the paper. Depending on the
- * chosen interpreter, it simply ignores instructions on vertical stems
- * to arrive at very similar results.
- *
- * The following example code demonstrates how to deactivate subpixel
- * hinting (omitting the error handling).
- *
- * {
- * <a href="ft2-base_interface.html#FT_Library">FT_Library</a> library;
- * <a href="ft2-base_interface.html#FT_Face">FT_Face</a> face;
- * <a href="ft2-basic_types.html#FT_UInt">FT_UInt</a> interpreter_version = <a href="ft2-tt_driver.html#TT_INTERPRETER_VERSION_35">TT_INTERPRETER_VERSION_35</a>;
- *
- *
- * <a href="ft2-base_interface.html#FT_Init_FreeType">FT_Init_FreeType</a>( &amp;library );
- *
- * <a href="ft2-module_management.html#FT_Property_Set">FT_Property_Set</a>( library, "truetype",
- * "interpreter-version",
- * &amp;interpreter_version );
- * }
- *
- * @note:
- * This property can be used with @<a href="ft2-module_management.html#FT_Property_Get">FT_Property_Get</a> also.
- *
- * This property can be set via the `FREETYPE_PROPERTIES' environment
- * variable (using values `35', `38', or `40').
- */
+
+<p>Currently, three versions are available, two representing the bytecode interpreter with subpixel hinting support (old &lsquo;Infinality&rsquo; code and new stripped-down and higher performance &lsquo;minimal&rsquo; code) and one without, respectively. The default is subpixel support if TT_CONFIG_OPTION_SUBPIXEL_HINTING is defined, and no subpixel support otherwise (since it isn't available then).</p>
+<p>If subpixel hinting is on, many TrueType bytecode instructions behave differently compared to B/W or grayscale rendering (except if &lsquo;native ClearType&rsquo; is selected by the font). Microsoft's main idea is to render at a much increased horizontal resolution, then sampling down the created output to subpixel precision. However, many older fonts are not suited to this and must be specially taken care of by applying (hardcoded) tweaks in Microsoft's interpreter.</p>
+<p>Details on subpixel hinting and some of the necessary tweaks can be found in Greg Hitchcock's whitepaper at &lsquo;<a href="http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx">http://www.microsoft.com/typography/cleartype/truetypecleartype.aspx</a>&rsquo;. Note that FreeType currently doesn't really &lsquo;subpixel hint&rsquo; (6x1, 6x2, or 6x5 supersampling) like discussed in the paper. Depending on the chosen interpreter, it simply ignores instructions on vertical stems to arrive at very similar results.</p>
+<p>The following example code demonstrates how to deactivate subpixel hinting (omitting the error handling).</p>
+<pre class="colored">
+ FT_Library library;
+ FT_Face face;
+ FT_UInt interpreter_version = TT_INTERPRETER_VERSION_35;
+
+
+ FT_Init_FreeType( &amp;library );
+
+ FT_Property_Set( library, "truetype",
+ "interpreter-version",
+ &amp;interpreter_version );
</pre>
+
+<h4>note</h4>
+<p>This property can be used with <a href="ft2-module_management.html#FT_Property_Get">FT_Property_Get</a> also.</p>
+<p>This property can be set via the &lsquo;FREETYPE_PROPERTIES&rsquo; environment variable (using values &lsquo;35&rsquo;, &lsquo;38&rsquo;, or &lsquo;40&rsquo;).</p>
+
<hr>
<table class="index-toc-link"><tr><td class="left">[<a href="ft2-index.html">Index</a>]</td><td class="middle">[<a href="#">Top</a>]</td><td class="right">[<a href="ft2-toc.html">TOC</a>]</td></tr></table></div>
@@ -207,7 +181,7 @@
<h4>note</h4>
<p>This property controls the behaviour of the bytecode interpreter and thus how outlines get hinted. It does <b>not</b> control how glyph get rasterized! In particular, it does not control subpixel color filtering.</p>
-<p>If FreeType has not been compiled with the configuration option FT_CONFIG_OPTION_SUBPIXEL_HINTING, selecting version&nbsp;38 or&nbsp;40 causes an &lsquo;FT_Err_Unimplemented_Feature&rsquo; error.</p>
+<p>If FreeType has not been compiled with the configuration option TT_CONFIG_OPTION_SUBPIXEL_HINTING, selecting version&nbsp;38 or&nbsp;40 causes an &lsquo;FT_Err_Unimplemented_Feature&rsquo; error.</p>
<p>Depending on the graphics framework, Microsoft uses different bytecode and rendering engines. As a consequence, the version numbers returned by a call to the &lsquo;GETINFO&rsquo; bytecode instruction are more convoluted than desired.</p>
<p>Here are two tables that try to shed some light on the possible values for the MS rasterizer engine, together with the additional features introduced by it.</p>
<pre class="colored">