<?php
include_once $_SERVER['DOCUMENT_ROOT'] . '/include/shared-manual.inc';
$TOC = array();
$TOC_DEPRECATED = array();
$PARENTS = array();
include_once dirname(__FILE__) ."/toc/ref.image.inc";
$setup = array (
  'home' => 
  array (
    0 => 'index.php',
    1 => 'PHP Manual',
  ),
  'head' => 
  array (
    0 => 'UTF-8',
    1 => 'it',
  ),
  'this' => 
  array (
    0 => 'function.imageline.php',
    1 => 'imageline',
    2 => 'Draw a line',
  ),
  'up' => 
  array (
    0 => 'ref.image.php',
    1 => 'GD and Image Funzioni',
  ),
  'prev' => 
  array (
    0 => 'function.imagelayereffect.php',
    1 => 'imagelayereffect',
  ),
  'next' => 
  array (
    0 => 'function.imageloadfont.php',
    1 => 'imageloadfont',
  ),
  'alternatives' => 
  array (
  ),
  'source' => 
  array (
    'lang' => 'en',
    'path' => 'reference/image/functions/imageline.xml',
  ),
  'history' => 
  array (
  ),
);
$setup["toc"] = $TOC;
$setup["toc_deprecated"] = $TOC_DEPRECATED;
$setup["parents"] = $PARENTS;
manual_setup($setup);

contributors($setup);

?>
<div id="function.imageline" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">imageline</h1>
  <p class="verinfo">(PHP 4, PHP 5, PHP 7, PHP 8)</p><p class="refpurpose"><span class="refname">imageline</span> &mdash; <span class="dc-title">Draw a line</span></p>

 </div>
 <div class="refsect1 description" id="refsect1-function.imageline-description">
  <h3 class="title">Descrizione</h3>
  <div class="methodsynopsis dc-description">
   <span class="methodname"><strong>imageline</strong></span>(<br>&nbsp;&nbsp;&nbsp;&nbsp;<span class="methodparam"><span class="type"><a href="class.gdimage.php" class="type GdImage">GdImage</a></span> <code class="parameter">$image</code></span>,<br>&nbsp;&nbsp;&nbsp;&nbsp;<span class="methodparam"><span class="type"><a href="language.types.integer.php" class="type int">int</a></span> <code class="parameter">$x1</code></span>,<br>&nbsp;&nbsp;&nbsp;&nbsp;<span class="methodparam"><span class="type"><a href="language.types.integer.php" class="type int">int</a></span> <code class="parameter">$y1</code></span>,<br>&nbsp;&nbsp;&nbsp;&nbsp;<span class="methodparam"><span class="type"><a href="language.types.integer.php" class="type int">int</a></span> <code class="parameter">$x2</code></span>,<br>&nbsp;&nbsp;&nbsp;&nbsp;<span class="methodparam"><span class="type"><a href="language.types.integer.php" class="type int">int</a></span> <code class="parameter">$y2</code></span>,<br>&nbsp;&nbsp;&nbsp;&nbsp;<span class="methodparam"><span class="type"><a href="language.types.integer.php" class="type int">int</a></span> <code class="parameter">$color</code></span><br>): <span class="type"><a href="language.types.singleton.php" class="type true">true</a></span></div>

  <p class="para rdfs-comment">
   Draws a line between the two given points.
  </p>
 </div>

 <div class="refsect1 parameters" id="refsect1-function.imageline-parameters">
  <h3 class="title">Elenco dei parametri</h3>
  <p class="para">
   <dl>
    <dt><code class="parameter">
image</code></dt><dd><p class="para">Una risorsa immagine, restituita da una delle funzioni di creazione immagine, 
come <span class="function"><a href="function.imagecreatetruecolor.php" class="function">imagecreatetruecolor()</a></span>.</p></dd>
    
     <dt><code class="parameter">x1</code></dt>
     <dd>
      <p class="para">
       x-coordinate for first point.
      </p>
     </dd>
    
    
     <dt><code class="parameter">y1</code></dt>
     <dd>
      <p class="para">
       y-coordinate for first point.
      </p>
     </dd>
    
    
     <dt><code class="parameter">x2</code></dt>
     <dd>
      <p class="para">
       x-coordinate for second point.
      </p>
     </dd>
    
    
     <dt><code class="parameter">y2</code></dt>
     <dd>
      <p class="para">
       y-coordinate for second point.
      </p>
     </dd>
    
    
     <dt><code class="parameter">color</code></dt>
     <dd>
      <p class="para">
       The line color. A color identifier created with <span class="function"><a href="function.imagecolorallocate.php" class="function">imagecolorallocate()</a></span>.
      </p>
     </dd>
    
   </dl>
  </p>
 </div>

 <div class="refsect1 returnvalues" id="refsect1-function.imageline-returnvalues">
  <h3 class="title">Valori restituiti</h3>
  <p class="para">
   Always returns <strong><code><a href="reserved.constants.php#constant.true">true</a></code></strong>.
  </p>
 </div>


 <div class="refsect1 changelog" id="refsect1-function.imageline-changelog">
  <h3 class="title">Log delle modifiche</h3>
  <table class="doctable informaltable">
   
    <thead>
     <tr>
      <th>Versione</th>
      <th>Descrizione</th>
     </tr>

    </thead>

    <tbody class="tbody">
     <tr>
 <td>8.0.0</td>
 <td>
  <code class="parameter">image</code> expects a <span class="classname"><a href="class.gdimage.php" class="classname">GdImage</a></span>
  instance now; previously, a valid <code class="literal">gd</code> <span class="type"><a href="language.types.resource.php" class="type resource">resource</a></span> was expected.
 </td>
</tr>

    </tbody>
   
  </table>

 </div>


 <div class="refsect1 examples" id="refsect1-function.imageline-examples">
  <h3 class="title">Esempi</h3>
  <p class="para">
   <div class="example" id="example-1">
    <p><strong>Example #1 Drawing a thick line</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br /><br /></span><span style="color: #007700">function </span><span style="color: #0000BB">imagelinethick</span><span style="color: #007700">(</span><span style="color: #0000BB">$image</span><span style="color: #007700">, </span><span style="color: #0000BB">$x1</span><span style="color: #007700">, </span><span style="color: #0000BB">$y1</span><span style="color: #007700">, </span><span style="color: #0000BB">$x2</span><span style="color: #007700">, </span><span style="color: #0000BB">$y2</span><span style="color: #007700">, </span><span style="color: #0000BB">$color</span><span style="color: #007700">, </span><span style="color: #0000BB">$thick </span><span style="color: #007700">= </span><span style="color: #0000BB">1</span><span style="color: #007700">)<br />{<br />    </span><span style="color: #FF8000">/* this way it works well only for orthogonal lines<br />    imagesetthickness($image, $thick);<br />    return imageline($image, $x1, $y1, $x2, $y2, $color);<br />    */<br />    </span><span style="color: #007700">if (</span><span style="color: #0000BB">$thick </span><span style="color: #007700">== </span><span style="color: #0000BB">1</span><span style="color: #007700">) {<br />        return </span><span style="color: #0000BB">imageline</span><span style="color: #007700">(</span><span style="color: #0000BB">$image</span><span style="color: #007700">, </span><span style="color: #0000BB">$x1</span><span style="color: #007700">, </span><span style="color: #0000BB">$y1</span><span style="color: #007700">, </span><span style="color: #0000BB">$x2</span><span style="color: #007700">, </span><span style="color: #0000BB">$y2</span><span style="color: #007700">, </span><span style="color: #0000BB">$color</span><span style="color: #007700">);<br />    }<br />    </span><span style="color: #0000BB">$t </span><span style="color: #007700">= </span><span style="color: #0000BB">$thick </span><span style="color: #007700">/ </span><span style="color: #0000BB">2 </span><span style="color: #007700">- </span><span style="color: #0000BB">0.5</span><span style="color: #007700">;<br />    if (</span><span style="color: #0000BB">$x1 </span><span style="color: #007700">== </span><span style="color: #0000BB">$x2 </span><span style="color: #007700">|| </span><span style="color: #0000BB">$y1 </span><span style="color: #007700">== </span><span style="color: #0000BB">$y2</span><span style="color: #007700">) {<br />        return </span><span style="color: #0000BB">imagefilledrectangle</span><span style="color: #007700">(</span><span style="color: #0000BB">$image</span><span style="color: #007700">, </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">min</span><span style="color: #007700">(</span><span style="color: #0000BB">$x1</span><span style="color: #007700">, </span><span style="color: #0000BB">$x2</span><span style="color: #007700">) - </span><span style="color: #0000BB">$t</span><span style="color: #007700">), </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">min</span><span style="color: #007700">(</span><span style="color: #0000BB">$y1</span><span style="color: #007700">, </span><span style="color: #0000BB">$y2</span><span style="color: #007700">) - </span><span style="color: #0000BB">$t</span><span style="color: #007700">), </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">max</span><span style="color: #007700">(</span><span style="color: #0000BB">$x1</span><span style="color: #007700">, </span><span style="color: #0000BB">$x2</span><span style="color: #007700">) + </span><span style="color: #0000BB">$t</span><span style="color: #007700">), </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">max</span><span style="color: #007700">(</span><span style="color: #0000BB">$y1</span><span style="color: #007700">, </span><span style="color: #0000BB">$y2</span><span style="color: #007700">) + </span><span style="color: #0000BB">$t</span><span style="color: #007700">), </span><span style="color: #0000BB">$color</span><span style="color: #007700">);<br />    }<br />    </span><span style="color: #0000BB">$k </span><span style="color: #007700">= (</span><span style="color: #0000BB">$y2 </span><span style="color: #007700">- </span><span style="color: #0000BB">$y1</span><span style="color: #007700">) / (</span><span style="color: #0000BB">$x2 </span><span style="color: #007700">- </span><span style="color: #0000BB">$x1</span><span style="color: #007700">); </span><span style="color: #FF8000">//y = kx + q<br />    </span><span style="color: #0000BB">$a </span><span style="color: #007700">= </span><span style="color: #0000BB">$t </span><span style="color: #007700">/ </span><span style="color: #0000BB">sqrt</span><span style="color: #007700">(</span><span style="color: #0000BB">1 </span><span style="color: #007700">+ </span><span style="color: #0000BB">pow</span><span style="color: #007700">(</span><span style="color: #0000BB">$k</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">));<br />    </span><span style="color: #0000BB">$points </span><span style="color: #007700">= array(<br />        </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">$x1 </span><span style="color: #007700">- (</span><span style="color: #0000BB">1</span><span style="color: #007700">+</span><span style="color: #0000BB">$k</span><span style="color: #007700">)*</span><span style="color: #0000BB">$a</span><span style="color: #007700">), </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">$y1 </span><span style="color: #007700">+ (</span><span style="color: #0000BB">1</span><span style="color: #007700">-</span><span style="color: #0000BB">$k</span><span style="color: #007700">)*</span><span style="color: #0000BB">$a</span><span style="color: #007700">),<br />        </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">$x1 </span><span style="color: #007700">- (</span><span style="color: #0000BB">1</span><span style="color: #007700">-</span><span style="color: #0000BB">$k</span><span style="color: #007700">)*</span><span style="color: #0000BB">$a</span><span style="color: #007700">), </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">$y1 </span><span style="color: #007700">- (</span><span style="color: #0000BB">1</span><span style="color: #007700">+</span><span style="color: #0000BB">$k</span><span style="color: #007700">)*</span><span style="color: #0000BB">$a</span><span style="color: #007700">),<br />        </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">$x2 </span><span style="color: #007700">+ (</span><span style="color: #0000BB">1</span><span style="color: #007700">+</span><span style="color: #0000BB">$k</span><span style="color: #007700">)*</span><span style="color: #0000BB">$a</span><span style="color: #007700">), </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">$y2 </span><span style="color: #007700">- (</span><span style="color: #0000BB">1</span><span style="color: #007700">-</span><span style="color: #0000BB">$k</span><span style="color: #007700">)*</span><span style="color: #0000BB">$a</span><span style="color: #007700">),<br />        </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">$x2 </span><span style="color: #007700">+ (</span><span style="color: #0000BB">1</span><span style="color: #007700">-</span><span style="color: #0000BB">$k</span><span style="color: #007700">)*</span><span style="color: #0000BB">$a</span><span style="color: #007700">), </span><span style="color: #0000BB">round</span><span style="color: #007700">(</span><span style="color: #0000BB">$y2 </span><span style="color: #007700">+ (</span><span style="color: #0000BB">1</span><span style="color: #007700">+</span><span style="color: #0000BB">$k</span><span style="color: #007700">)*</span><span style="color: #0000BB">$a</span><span style="color: #007700">),<br />    );<br />    </span><span style="color: #0000BB">imagefilledpolygon</span><span style="color: #007700">(</span><span style="color: #0000BB">$image</span><span style="color: #007700">, </span><span style="color: #0000BB">$points</span><span style="color: #007700">, </span><span style="color: #0000BB">4</span><span style="color: #007700">, </span><span style="color: #0000BB">$color</span><span style="color: #007700">);<br />    return </span><span style="color: #0000BB">imagepolygon</span><span style="color: #007700">(</span><span style="color: #0000BB">$image</span><span style="color: #007700">, </span><span style="color: #0000BB">$points</span><span style="color: #007700">, </span><span style="color: #0000BB">4</span><span style="color: #007700">, </span><span style="color: #0000BB">$color</span><span style="color: #007700">);<br />}<br /><br /></span><span style="color: #0000BB">?&gt;</span></span></code></div>
    </div>

   </div>
  </p>
 </div>

 <div class="refsect1 seealso" id="refsect1-function.imageline-seealso">
  <h3 class="title">Vedere anche:</h3>
  <ul class="simplelist">
   <li><span class="function"><a href="function.imagecreatetruecolor.php" class="function" rel="rdfs-seeAlso">imagecreatetruecolor()</a> - Create a new true color image</span></li>
   <li><span class="function"><a href="function.imagecolorallocate.php" class="function" rel="rdfs-seeAlso">imagecolorallocate()</a> - Allocate a color for an image</span></li>
  </ul>
 </div>

</div><?php manual_footer($setup); ?>