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diff --git a/freetype/docs/reference/ft2-cff_driver.html b/freetype/docs/reference/ft2-cff_driver.html index 7ae308de6..f1de5661a 100644 --- a/freetype/docs/reference/ft2-cff_driver.html +++ b/freetype/docs/reference/ft2-cff_driver.html @@ -3,50 +3,113 @@ <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> -<title>FreeType-2.5.3 API Reference</title> +<title>FreeType-2.5.5 API Reference</title> <style type="text/css"> + a:link { color: #0000EF; } + a:visited { color: #51188E; } + a:hover { color: #FF0000; } + body { font-family: Verdana, Geneva, Arial, Helvetica, serif; color: #000000; - background: #FFFFFF; } + background: #FFFFFF; + width: 87%; + margin: auto; } + + div.section { width: 75%; + margin: auto; } + div.section hr { margin: 4ex 0 1ex 0; } + div.section h4 { background-color: #EEEEFF; + font-size: medium; + font-style: oblique; + font-weight: bold; + margin: 3ex 0 1.5ex 9%; + padding: 0.3ex 0 0.3ex 1%; } + div.section p { margin: 1.5ex 0 1.5ex 10%; } + div.section pre { margin: 3ex 0 3ex 9%; + background-color: #D6E8FF; + padding: 2ex 0 2ex 1%; } + div.section table.fields { width: 90%; + margin: 1.5ex 0 1.5ex 10%; } + div.section table.toc { width: 95%; + margin: 1.5ex 0 1.5ex 5%; } + div.timestamp { text-align: center; + font-size: 69%; + margin: 1.5ex 0 1.5ex 0; } - p { text-align: justify; } h1 { text-align: center; } - li { text-align: justify; } - td { padding: 0 0.5em 0 0.5em; } - td.left { padding: 0 0.5em 0 0.5em; - text-align: left; } + h3 { font-size: medium; + margin: 4ex 0 1.5ex 0; } - a:link { color: #0000EF; } - a:visited { color: #51188E; } - a:hover { color: #FF0000; } + p { text-align: justify; } + + pre.colored { color: blue; } span.keyword { font-family: monospace; text-align: left; white-space: pre; color: darkblue; } - pre.colored { color: blue; } + table.fields td.val { font-weight: bold; + text-align: right; + width: 30%; + vertical-align: baseline; + padding: 1ex 1em 1ex 0; } + table.fields td.desc { vertical-align: baseline; + padding: 1ex 0 1ex 1em; } + table.fields td.desc p:first-child { margin: 0; } + table.fields td.desc p { margin: 1.5ex 0 0 0; } + table.index { margin: 6ex auto 6ex auto; + border: 0; + border-collapse: separate; + border-spacing: 1em 0.3ex; } + table.index tr { padding: 0; } + table.index td { padding: 0; } + table.index-toc-link { width: 100%; + border: 0; + border-spacing: 0; + margin: 1ex 0 1ex 0; } + table.index-toc-link td.left { padding: 0 0.5em 0 0.5em; + font-size: 83%; + text-align: left; } + table.index-toc-link td.middle { padding: 0 0.5em 0 0.5em; + font-size: 83%; + text-align: center; } + table.index-toc-link td.right { padding: 0 0.5em 0 0.5em; + font-size: 83%; + text-align: right; } + table.synopsis { margin: 6ex auto 6ex auto; + border: 0; + border-collapse: separate; + border-spacing: 2em 0.6ex; } + table.synopsis tr { padding: 0; } + table.synopsis td { padding: 0; } + table.toc td.link { width: 30%; + text-align: right; + vertical-align: baseline; + padding: 1ex 1em 1ex 0; } + table.toc td.desc { vertical-align: baseline; + padding: 1ex 0 1ex 1em; + text-align: left; } + table.toc td.desc p:first-child { margin: 0; + text-align: left; } + table.toc td.desc p { margin: 1.5ex 0 0 0; + text-align: left; } - ul.empty { list-style-type: none; } </style> </head> <body> -<table align=center><tr><td><font size=-1>[<a href="ft2-index.html">Index</a>]</font></td> -<td width="100%"></td> -<td><font size=-1>[<a href="ft2-toc.html">TOC</a>]</font></td></tr></table> -<center><h1>FreeType-2.5.3 API Reference</h1></center> +<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-2.5.5 API Reference</h1> -<center><h1> -The CFF driver -</h1></center> +<h1>The CFF driver</h1> <h2>Synopsis</h2> -<table align=center cellspacing=5 cellpadding=0 border=0> -<tr><td></td><td><a href="#hinting-engine">hinting-engine</a></td><td></td><td><a href="#no-stem-darkening">no-stem-darkening</a></td><td></td><td></td></tr> -<tr><td></td><td><a href="#FT_CFF_HINTING_XXX">FT_CFF_HINTING_XXX</a></td><td></td><td><a href="#darkening-parameters">darkening-parameters</a></td><td></td><td></td></tr> -</table><br><br> +<table class="synopsis"> +<tr><td><a href="#hinting-engine">hinting-engine</a></td><td><a href="#darkening-parameters">darkening-parameters</a></td><td><a href="#FT_CFF_HINTING_XXX">FT_CFF_HINTING_XXX</a></td></tr> +<tr><td><a href="#no-stem-darkening">no-stem-darkening</a></td><td> </td><td></td></tr> +</table> + -<table align=center width="87%"><tr><td> <p>While FreeType's CFF driver doesn't expose API functions by itself, it is possible to control its behaviour with <a href="ft2-module_management.html#FT_Property_Set">FT_Property_Set</a> and <a href="ft2-module_management.html#FT_Property_Get">FT_Property_Get</a>. The list below gives the available properties together with the necessary macros and structures.</p> <p>The CFF driver's module name is ‘cff’.</p> <p><b>Hinting</b> <b>and</b> <b>antialiasing</b> <b>principles</b> <b>of</b> <b>the</b> <b>new</b> <b>engine</b></p> @@ -57,10 +120,10 @@ The CFF driver <p>2) Aligment in the vertical direction: Weights and spacing along the y axis are less critical; what is much more important is the visual alignment of related features (like cap-height and x-height). The sense of alignment for these is enhanced by the sharpness of grid-fit edges, while the cruder vertical resolution (full pixels instead of 1/3 pixels) is less of a problem.</p> <p>On the technical side, horizontal alignment zones for ascender, x-height, and other important height values (traditionally called ‘blue zones’) as defined in the font are positioned independently, each being rounded to the nearest pixel edge, taking care of overshoot suppression at small sizes, stem darkening, and scaling.</p> <p>Hstems (this is, hint values defined in the font to help align horizontal features) that fall within a blue zone are said to be ‘captured’ and are aligned to that zone. Uncaptured stems are moved in one of four ways, top edge up or down, bottom edge up or down. Unless there are conflicting hstems, the smallest movement is taken to minimize distortion.</p> -</td></tr></table><br> -<table align=center width="75%"><tr><td> -<h4><a name="hinting-engine">hinting-engine</a></h4> -<table align=center width="87%"><tr><td> + +<div class="section"> +<h3 id="hinting-engine">hinting-engine</h3> + <p>Thanks to Adobe, which contributed a new hinting (and parsing) engine, an application can select between ‘freetype’ and ‘adobe’ if compiled with CFF_CONFIG_OPTION_OLD_ENGINE. If this configuration macro isn't defined, ‘hinting-engine’ does nothing.</p> <p>The default engine is ‘freetype’ if CFF_CONFIG_OPTION_OLD_ENGINE is defined, and ‘adobe’ otherwise.</p> <p>The following example code demonstrates how to select Adobe's hinting engine (omitting the error handling).</p> @@ -74,51 +137,16 @@ The CFF driver FT_Property_Set( library, "cff", "hinting-engine", &hinting_engine ); </pre> -</td></tr></table><br> -<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>note</b></em></td></tr><tr><td> + +<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> -</td></tr></table> -</td></tr></table> -<hr width="75%"> -<table align=center width="75%"><tr><td><font size=-2>[<a href="ft2-index.html">Index</a>]</font></td> -<td width="100%"></td> -<td><font size=-2>[<a href="ft2-toc.html">TOC</a>]</font></td></tr></table> - -<table align=center width="75%"><tr><td> -<h4><a name="FT_CFF_HINTING_XXX">FT_CFF_HINTING_XXX</a></h4> -<table align=center width="87%"><tr><td> -Defined in FT_CFF_DRIVER_H (ftcffdrv.h). -</td></tr></table><br> -<table align=center width="87%"><tr bgcolor="#D6E8FF"><td><pre> - -#define <a href="ft2-cff_driver.html#FT_CFF_HINTING_XXX">FT_CFF_HINTING_FREETYPE</a> 0 -#define <a href="ft2-cff_driver.html#FT_CFF_HINTING_XXX">FT_CFF_HINTING_ADOBE</a> 1 - -</pre></table><br> -<table align=center width="87%"><tr><td> -<p>A list of constants used for the <a href="ft2-cff_driver.html#hinting-engine">hinting-engine</a> property to select the hinting engine for CFF fonts.</p> -</td></tr></table><br> -<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>values</b></em></td></tr><tr><td> -<p></p> -<table cellpadding=3 border=0> -<tr valign=top><td colspan=0><b>FT_CFF_HINTING_FREETYPE</b></td></tr> -<tr valign=top><td></td><td> -<p>Use the old FreeType hinting engine.</p> -</td></tr> -<tr valign=top><td><b>FT_CFF_HINTING_ADOBE</b></td><td> -<p>Use the hinting engine contributed by Adobe.</p> -</td></tr> -</table> -</td></tr></table> -</td></tr></table> -<hr width="75%"> -<table align=center width="75%"><tr><td><font size=-2>[<a href="ft2-index.html">Index</a>]</font></td> -<td width="100%"></td> -<td><font size=-2>[<a href="ft2-toc.html">TOC</a>]</font></td></tr></table> - -<table align=center width="75%"><tr><td> -<h4><a name="no-stem-darkening">no-stem-darkening</a></h4> -<table align=center width="87%"><tr><td> + +<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> + +<div class="section"> +<h3 id="no-stem-darkening">no-stem-darkening</h3> + <p>By default, the Adobe CFF engine darkens stems at smaller sizes, regardless of hinting, to enhance contrast. This feature requires a rendering system with proper gamma correction. Setting this property, stem darkening gets switched off.</p> <p>Note that stem darkening is never applied if <a href="ft2-base_interface.html#FT_LOAD_XXX">FT_LOAD_NO_SCALE</a> is set.</p> <pre class="colored"> @@ -131,19 +159,16 @@ Defined in FT_CFF_DRIVER_H (ftcffdrv.h). FT_Property_Set( library, "cff", "no-stem-darkening", &no_stem_darkening ); </pre> -</td></tr></table><br> -<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>note</b></em></td></tr><tr><td> + +<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> -</td></tr></table> -</td></tr></table> -<hr width="75%"> -<table align=center width="75%"><tr><td><font size=-2>[<a href="ft2-index.html">Index</a>]</font></td> -<td width="100%"></td> -<td><font size=-2>[<a href="ft2-toc.html">TOC</a>]</font></td></tr></table> - -<table align=center width="75%"><tr><td> -<h4><a name="darkening-parameters">darkening-parameters</a></h4> -<table align=center width="87%"><tr><td> + +<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> + +<div class="section"> +<h3 id="darkening-parameters">darkening-parameters</h3> + <p>By default, the Adobe CFF engine darkens stems as follows (if the ‘no-stem-darkening’ property isn't set):</p> <pre class="colored"> stem width <= 0.5px: darkening amount = 0.4px @@ -151,7 +176,7 @@ Defined in FT_CFF_DRIVER_H (ftcffdrv.h). stem width = 1.667px: darkening amount = 0.275px stem width >= 2.333px: darkening amount = 0px </pre> -<p>and piecewise linear in-between. Using the ‘darkening-parameters’ property, these four control points can be changed, as the following example demonstrates.</p> +<p>and piecewise linear in-between. At configuration time, these four control points can be set with the macro ‘CFF_CONFIG_OPTION_DARKENING_PARAMETERS’. At runtime, the control points can be changed using the ‘darkening-parameters’ property, as the following example demonstrates.</p> <pre class="colored"> FT_Library library; FT_Int darken_params[8] = { 500, 300, // x1, y1 @@ -166,15 +191,35 @@ Defined in FT_CFF_DRIVER_H (ftcffdrv.h). "darkening-parameters", darken_params ); </pre> <p>The x values give the stem width, and the y values the darkening amount. The unit is 1000th of pixels. All coordinate values must be positive; the x values must be monotonically increasing; the y values must be monotonically decreasing and smaller than or equal to 500 (corresponding to half a pixel); the slope of each linear piece must be shallower than -1 (e.g., -.4).</p> -</td></tr></table><br> -<table align=center width="87%" cellpadding=5><tr bgcolor="#EEEEFF"><td><em><b>note</b></em></td></tr><tr><td> + +<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> -</td></tr></table> -</td></tr></table> -<hr width="75%"> -<table align=center width="75%"><tr><td><font size=-2>[<a href="ft2-index.html">Index</a>]</font></td> -<td width="100%"></td> -<td><font size=-2>[<a href="ft2-toc.html">TOC</a>]</font></td></tr></table> + +<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> + +<div class="section"> +<h3 id="FT_CFF_HINTING_XXX">FT_CFF_HINTING_XXX</h3> +<p>Defined in FT_CFF_DRIVER_H (ftcffdrv.h).</p> +<pre> +#define <a href="ft2-cff_driver.html#FT_CFF_HINTING_FREETYPE">FT_CFF_HINTING_FREETYPE</a> 0 +#define <a href="ft2-cff_driver.html#FT_CFF_HINTING_ADOBE">FT_CFF_HINTING_ADOBE</a> 1 +</pre> + +<p>A list of constants used for the <a href="ft2-cff_driver.html#hinting-engine">hinting-engine</a> property to select the hinting engine for CFF fonts.</p> + +<h4>values</h4> +<table class="fields"> +<tr><td class="val" id="FT_CFF_HINTING_FREETYPE">FT_CFF_HINTING_FREETYPE</td><td class="desc"> +<p>Use the old FreeType hinting engine.</p> +</td></tr> +<tr><td class="val" id="FT_CFF_HINTING_ADOBE">FT_CFF_HINTING_ADOBE</td><td class="desc"> +<p>Use the hinting engine contributed by Adobe.</p> +</td></tr> +</table> + +<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> </body> </html> |