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<h1 class="refname">imageline</h1>
<p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">imageline</span> — <span class="dc-title">Draw a line</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.imageline-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">bool</span> <span class="methodname"><strong>imageline</strong></span>
( <span class="methodparam"><span class="type">resource</span> <code class="parameter">$image</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$x1</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$y1</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$x2</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$y2</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$color</code></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">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">
image</code></em></span><dd>
<p class="para">An image resource, returned by one of the image creation functions,
such as <span class="function"><a href="function.imagecreatetruecolor.html" class="function">imagecreatetruecolor()</a></span>.</p></dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">x1</code></em></span>
<dd>
<p class="para">
x-coordinate for first point.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">y1</code></em></span>
<dd>
<p class="para">
y-coordinate for first point.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">x2</code></em></span>
<dd>
<p class="para">
x-coordinate for second point.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">y2</code></em></span>
<dd>
<p class="para">
y-coordinate for second point.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">color</code></em></span>
<dd>
<p class="para">
The line color. A color identifier created with
<span class="function"><a href="function.imagecolorallocate.html" class="function">imagecolorallocate()</a></span>.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.imageline-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns <strong><code>TRUE</code></strong> on success or <strong><code>FALSE</code></strong> on failure.
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.imageline-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-3259">
<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"><?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">?></span>
</span>
</code></div>
</div>
</div>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.imageline-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.imagecreatetruecolor.html" class="function" rel="rdfs-seeAlso">imagecreatetruecolor()</a> - Create a new true color image</span></li>
<li class="member"> <span class="function"><a href="function.imagecolorallocate.html" class="function" rel="rdfs-seeAlso">imagecolorallocate()</a> - Allocate a color for an image</span></li>
</ul>
</p>
</div>
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