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<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision: 1.13 $ -->
<refentry xml:id="function.imageline" xmlns="http://docbook.org/ns/docbook">
<refnamediv>
<refname>imageline</refname>
<refpurpose>Draw a line</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<methodsynopsis>
<type>bool</type><methodname>imageline</methodname>
<methodparam><type>resource</type><parameter>image</parameter></methodparam>
<methodparam><type>int</type><parameter>x1</parameter></methodparam>
<methodparam><type>int</type><parameter>y1</parameter></methodparam>
<methodparam><type>int</type><parameter>x2</parameter></methodparam>
<methodparam><type>int</type><parameter>y2</parameter></methodparam>
<methodparam><type>int</type><parameter>color</parameter></methodparam>
</methodsynopsis>
<para>
Draws a line between the two given points.
</para>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<para>
<variablelist>
&gd.image.description;
<varlistentry>
<term><parameter>x1</parameter></term>
<listitem>
<para>
x-coordinate for first point.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>y1</parameter></term>
<listitem>
<para>
y-coordinate for first point.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>x2</parameter></term>
<listitem>
<para>
x-coordinate for second point.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>y2</parameter></term>
<listitem>
<para>
y-coordinate for second point.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>color</parameter></term>
<listitem>
<para>
The line color. A color identifier created with
<function>imagecolorallocate</function>.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
&return.success;
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<para>
<example>
<title>Drawing a thick line</title>
<programlisting role="php">
<![CDATA[
<?php
function imagelinethick($image, $x1, $y1, $x2, $y2, $color, $thick = 1)
{
/* this way it works well only for orthogonal lines
imagesetthickness($image, $thick);
return imageline($image, $x1, $y1, $x2, $y2, $color);
*/
if ($thick == 1) {
return imageline($image, $x1, $y1, $x2, $y2, $color);
}
$t = $thick / 2 - 0.5;
if ($x1 == $x2 || $y1 == $y2) {
return imagefilledrectangle($image, round(min($x1, $x2) - $t), round(min($y1, $y2) - $t), round(max($x1, $x2) + $t), round(max($y1, $y2) + $t), $color);
}
$k = ($y2 - $y1) / ($x2 - $x1); //y = kx + q
$a = $t / sqrt(1 + pow($k, 2));
$points = array(
round($x1 - (1+$k)*$a), round($y1 + (1-$k)*$a),
round($x1 - (1-$k)*$a), round($y1 - (1+$k)*$a),
round($x2 + (1+$k)*$a), round($y2 - (1-$k)*$a),
round($x2 + (1-$k)*$a), round($y2 + (1+$k)*$a),
);
imagefilledpolygon($image, $points, 4, $color);
return imagepolygon($image, $points, 4, $color);
}
?>
]]>
</programlisting>
</example>
</para>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<para>
<simplelist>
<member><function>imagecreatetruecolor</function></member>
<member><function>imagecolorallocate</function></member>
</simplelist>
</para>
</refsect1>
</refentry>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"../../../../manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->
|
