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diff --git a/lib/gs/doc/src/gs_chapter5.xmlsrc b/lib/gs/doc/src/gs_chapter5.xmlsrc new file mode 100644 index 0000000000..fb60272598 --- /dev/null +++ b/lib/gs/doc/src/gs_chapter5.xmlsrc @@ -0,0 +1,69 @@ +<?xml version="1.0" encoding="latin1" ?> +<!DOCTYPE chapter SYSTEM "chapter.dtd"> + +<chapter> + <header> + <copyright> + <year>2000</year><year>2009</year> + <holder>Ericsson AB. All Rights Reserved.</holder> + </copyright> + <legalnotice> + The contents of this file are subject to the Erlang Public License, + Version 1.1, (the "License"); you may not use this file except in + compliance with the License. You should have received a copy of the + Erlang Public License along with this software. If not, it can be + retrieved online at http://www.erlang.org/. + + Software distributed under the License is distributed on an "AS IS" + basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See + the License for the specific language governing rights and limitations + under the License. + + </legalnotice> + + <title>Fonts</title> + <prepared></prepared> + <docno></docno> + <date></date> + <rev></rev> + <file>gs_chapter5.xml</file> + </header> + + <section> + <title>The Font Model</title> + <p>Text related objects can be handled with the font option <c><![CDATA[{font,Font}]]></c>. A <c><![CDATA[Font]]></c> is represented as a two or three tuple:</p> + <list type="bulleted"> + <item><c><![CDATA[{Family,Size}]]></c></item> + <item><c><![CDATA[{Family,Style,Size}]]></c></item> + </list> + <p>Examples of fonts are: <c><![CDATA[{times,12}]]></c>, <c><![CDATA[{symbol,bold,18}]]></c>, <c><![CDATA[{courier,[bold,italic],6}]]></c>, <c><![CDATA[{screen,12}]]></c>.</p> + <p>The most important requirement with the font model is to ensure that there is always a "best possible" font present. For example, if an application tries to use the font <c><![CDATA[{times,17}]]></c> on a computer system which does not have this font available, the <c><![CDATA[gs]]></c> font model automatically substitutes <c><![CDATA[{times,16}]]></c>.</p> + <p>Note that GS requires that the following fonts are available if using an X-server display:</p> + <list type="bulleted"> + <item>fixed</item> + <item>-*-courier-*</item> + <item>-*-times-*</item> + <item>-*-helvetica-*</item> + <item>-*-symbol-*</item> + <item>"-*-new century schoolbook-"</item> + <item>-*-screen-*</item> + </list> + <p>To find out which font is actually chosen by the <c><![CDATA[gs]]></c>, use the option <c><![CDATA[{choose_font,Font}]]></c>. For example, the following situation might occur:</p> + <pre><![CDATA[ +1> <input>G=gs:start().</input> +{1,<0.20.0>} +2><input>gs:read(G,{choose_font,{times,38}}).</input> +{times,[],38} +3> <input>gs:read(G,{choose_font,{screen,italic,6}}).</input> +{courier,italic,6} +4> + ]]></pre> + <p>When programming with fonts, it is often necessary to find the size of a string which uses a specific font. <c><![CDATA[{font_wh,Font}]]></c> returns the width and height of any string and any font. The following example illustrates its usage:</p> + <marker id="gs_fig6"></marker> + <image file="images/ex15.gif"> + <icaption>Font Examples</icaption> + </image> + <codeinclude file="examples/ex15.erl" tag="" type="erl"></codeinclude> + </section> +</chapter> + |