188 lines
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188 lines
24 KiB
HTML
<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><title>Adding icon and text objects to the graph</title><link rel="stylesheet" type="text/css" href="manual.css"><meta name="generator" content="DocBook XSL Stylesheets V1.76.0"><link rel="home" href="index.html" title="JpGraph Manual"><link rel="up" href="ch21.html" title="Chapter 21. Windrose"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Adding icon and text objects to the graph</th></tr><tr><td width="20%" align="left"> </td><th width="60%" align="center">Chapter 21. Windrose</th><td width="20%" align="right"> </td></tr></table><hr></div><div class="sect1" title="Adding icon and text objects to the graph"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2590039"></a>Adding icon and text objects to the graph</h2></div></div></div>
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<p>Windrose plots supports the ordinary way of adding icon and text objects to the graph. </p>
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<div class="sect2" title="Adding a text object"><div class="titlepage"><div><div><h3 class="title"><a name="id2590083"></a>Adding a text object</h3></div></div></div>
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<p>Text objects are added by first creating an instance of <code class="code">class Text</code>
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for each text needed and then adding the text to the graph with the usual call to
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<code class="code">WindroseGraph::Add()</code>. </p>
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<p>A basic text will only require two additional lines of code</p>
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<p>
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</p><div class="hl-main"><table class="hl-table" width="100%"><tr><td class="hl-gutter" align="right" valign="top"><pre>1
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</pre></td><td class="hl-main" valign="top"><pre><span class="hl-inlinetags"><?php</span><span class="hl-code">
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</span><span class="hl-var">$txt</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">Text</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">Simple string</span><span class="hl-quotes">'</span><span class="hl-code">,</span><span class="hl-number">20</span><span class="hl-code">,</span><span class="hl-number">20</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">Add</span><span class="hl-brackets">(</span><span class="hl-var">$txt</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-inlinetags">?></span></pre></td></tr></table></div><p>
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</p>
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<p>The following code snippet is slightly more complicated and will create a boxed
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text in the upper right corner of the graph. </p>
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<p>
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</p><div class="hl-main"><table class="hl-table" width="100%"><tr><td class="hl-gutter" align="right" valign="top"><pre>1
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</pre></td><td class="hl-main" valign="top"><pre><span class="hl-inlinetags"><?php</span><span class="hl-code">
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</span><span class="hl-comment">//</span><span class="hl-comment"> Add a boxed text</span><span class="hl-comment"></span><span class="hl-code">
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</span><span class="hl-var">$txt</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">Text</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$txt</span><span class="hl-code">-></span><span class="hl-identifier">SetFont</span><span class="hl-brackets">(</span><span class="hl-identifier">FF_ARIAL</span><span class="hl-code">,</span><span class="hl-identifier">FS_NORMAL</span><span class="hl-code">,</span><span class="hl-number">10</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$txt</span><span class="hl-code">-></span><span class="hl-identifier">Set</span><span class="hl-brackets">(</span><span class="hl-quotes">"</span><span class="hl-string">Arbitrary text</span><span class="hl-special">\n</span><span class="hl-string">on a</span><span class="hl-special">\n</span><span class="hl-string">Widrose Plot</span><span class="hl-quotes">"</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$txt</span><span class="hl-code">-></span><span class="hl-identifier">SetParagraphAlign</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">center</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$txt</span><span class="hl-code">-></span><span class="hl-identifier">SetPos</span><span class="hl-brackets">(</span><span class="hl-number">0</span><span class="hl-number">.95</span><span class="hl-code">,</span><span class="hl-number">0</span><span class="hl-number">.15</span><span class="hl-code">,</span><span class="hl-quotes">'</span><span class="hl-string">right</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$txt</span><span class="hl-code">-></span><span class="hl-identifier">SetBox</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">lightyellow</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$txt</span><span class="hl-code">-></span><span class="hl-identifier">SetShadow</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">Add</span><span class="hl-brackets">(</span><span class="hl-var">$txt</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-inlinetags">?></span></pre></td></tr></table></div><p>
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</p>
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<p>An example of adding text to a graph can for example be seen in <a class="xref" href="ch21s07.html#fig.windrose_ex5" title="Figure 21.23. (windrose_ex5.php)">Figure 21.23. <code class="uri"><a class="uri" href="example_src/windrose_ex5.html" target="_top">(<code class="filename">windrose_ex5.php</code>)</a></code> </a>. The snippet above adds a text at coordinates
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X=20, Y=20 using the default lower left corner as the text anchor point.</p>
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<p>
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</p><div class="note" title="Note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3>
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<p>To add a newline you must remember to use double-quotes to enclose the
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text otherwise the "\n" will only be interpreted literally. </p>
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</div><p>
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</p>
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<p>
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</p><div class="note" title="Note" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Note</h3>
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<p>Remember that the "text align", as adjusted with <code class="code">SetAlign()</code>,
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specifies the anchor point for the text, i.e. what part of the text is
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aligned with the specified position. </p>
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</div><p>
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</p>
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<p>To add many text strings it is often useful to specify them in an array and then
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have a loop creating the text object and add the text array of all the created
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objects to the graph as the following short snippet shows.</p>
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<p>
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</pre></td><td class="hl-main" valign="top"><pre><span class="hl-inlinetags"><?php</span><span class="hl-code">
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</span><span class="hl-comment">//</span><span class="hl-comment">--------------------------------------------------------------</span><span class="hl-comment"></span><span class="hl-code">
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</span><span class="hl-comment">//</span><span class="hl-comment"> Add texts to the graph</span><span class="hl-comment"></span><span class="hl-code">
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</span><span class="hl-comment">//</span><span class="hl-comment">--------------------------------------------------------------</span><span class="hl-comment"></span><span class="hl-code">
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</span><span class="hl-var">$txts</span><span class="hl-code"> = </span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-code">
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</span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">Textstring one ...</span><span class="hl-quotes">'</span><span class="hl-code">,</span><span class="hl-var">$tx1</span><span class="hl-code">,</span><span class="hl-var">$ty1</span><span class="hl-brackets">)</span><span class="hl-code">,
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</span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">Textstring two ...</span><span class="hl-quotes">'</span><span class="hl-code">,</span><span class="hl-var">$tx2</span><span class="hl-code">,</span><span class="hl-var">$ty2</span><span class="hl-brackets">)</span><span class="hl-code">,
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</span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">Textstring three ...</span><span class="hl-quotes">'</span><span class="hl-code">,</span><span class="hl-var">$tx3</span><span class="hl-code">,</span><span class="hl-var">$ty3</span><span class="hl-brackets">)</span><span class="hl-code">,
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</span><span class="hl-var">$n</span><span class="hl-code">=</span><span class="hl-identifier">count</span><span class="hl-brackets">(</span><span class="hl-var">$txts</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$t</span><span class="hl-code">=</span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-reserved">for</span><span class="hl-brackets">(</span><span class="hl-var">$i</span><span class="hl-code">=</span><span class="hl-number">0</span><span class="hl-code">; </span><span class="hl-var">$i</span><span class="hl-code"> < </span><span class="hl-var">$n</span><span class="hl-code">; ++</span><span class="hl-var">$i</span><span class="hl-brackets">)</span><span class="hl-brackets">{</span><span class="hl-code">
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</span><span class="hl-var">$t</span><span class="hl-brackets">[</span><span class="hl-var">$i</span><span class="hl-brackets">]</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">Text</span><span class="hl-brackets">(</span><span class="hl-var">$txts</span><span class="hl-brackets">[</span><span class="hl-var">$i</span><span class="hl-brackets">]</span><span class="hl-brackets">[</span><span class="hl-number">0</span><span class="hl-brackets">]</span><span class="hl-code">,</span><span class="hl-var">$txts</span><span class="hl-brackets">[</span><span class="hl-var">$i</span><span class="hl-brackets">]</span><span class="hl-brackets">[</span><span class="hl-number">1</span><span class="hl-brackets">]</span><span class="hl-code">,</span><span class="hl-var">$txts</span><span class="hl-brackets">[</span><span class="hl-var">$i</span><span class="hl-brackets">]</span><span class="hl-brackets">[</span><span class="hl-number">2</span><span class="hl-brackets">]</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$t</span><span class="hl-brackets">[</span><span class="hl-var">$i</span><span class="hl-brackets">]</span><span class="hl-code">-></span><span class="hl-identifier">SetFont</span><span class="hl-brackets">(</span><span class="hl-identifier">FF_ARIAL</span><span class="hl-code">,</span><span class="hl-identifier">FS_NORMAL</span><span class="hl-code">,</span><span class="hl-number">12</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$t</span><span class="hl-brackets">[</span><span class="hl-var">$i</span><span class="hl-brackets">]</span><span class="hl-code">-></span><span class="hl-identifier">SetColor</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">brown</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$t</span><span class="hl-brackets">[</span><span class="hl-var">$i</span><span class="hl-brackets">]</span><span class="hl-code">-></span><span class="hl-identifier">SetAlign</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">center</span><span class="hl-quotes">'</span><span class="hl-code">,</span><span class="hl-quotes">'</span><span class="hl-string">top</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-brackets">}</span><span class="hl-code">
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</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">Add</span><span class="hl-brackets">(</span><span class="hl-var">$t</span><span class="hl-brackets">)</span><span class="hl-code">;
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?></span></pre></td></tr></table></div><p>
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</p>
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</div>
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<div class="sect2" title="Adding icons to the graph"><div class="titlepage"><div><div><h3 class="title"><a name="id2590085"></a>Adding icons to the graph</h3></div></div></div>
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<p>Icons are added as instances of <code class="code">class IconPlot</code> to the graph (as usual
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with a call to <code class="code">WindroseGraph::Add()</code>). This means that to use icons the
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library module "<code class="filename">jpgraph_iconplot.php</code>" must first be included. </p>
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<p>The following example shows how to add a small "tornado" icon in the upper left
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corner of the graph. For more information on formatting icons that are added to a
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graph see <a class="xref" href="ch14s14.html" title="Adding icons (and small images) to the graph">Adding icons (and small images) to the graph</a></p>
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<p>
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</p><div class="caution" title="Caution" style="margin-left: 0.5in; margin-right: 0.5in;"><h3 class="title">Caution</h3>
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<p>Since Windrose graphs doesn't have a ny concept of linear scale the
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position of icons can only be specified as absolute pixels or fraction of
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the width/height.</p>
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</div><p>
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</p>
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<p>
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</p><div class="example"><a name="example.windrose_icon_ex1"></a><p class="title"><b>Example 21.5. Adding a "tornado" icon to the top left corner (<code class="filename">windrose_icon_ex1.php</code>) </b></p><div class="example-contents"> <div class="hl-main"><table class="hl-table" width="100%"><tr><td class="hl-gutter" align="right" valign="top"><pre>1
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</pre></td><td class="hl-main" valign="top"><pre><span class="hl-inlinetags"><?php</span><span class="hl-code">
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</span><span class="hl-reserved">require_once</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">jpgraph/jpgraph.php</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-reserved">require_once</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">jpgraph/jpgraph_windrose.php</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-reserved">require_once</span><span class="hl-code"> </span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">jpgraph/jpgraph_iconplot.php</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$data</span><span class="hl-code"> = </span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-code">
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</span><span class="hl-number">0</span><span class="hl-code"> => </span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-number">1</span><span class="hl-code">,</span><span class="hl-number">1</span><span class="hl-code">,</span><span class="hl-number">2</span><span class="hl-number">.5</span><span class="hl-code">,</span><span class="hl-number">4</span><span class="hl-brackets">)</span><span class="hl-code">,
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</span><span class="hl-number">1</span><span class="hl-code"> => </span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-number">3</span><span class="hl-code">,</span><span class="hl-number">4</span><span class="hl-code">,</span><span class="hl-number">1</span><span class="hl-code">,</span><span class="hl-number">4</span><span class="hl-brackets">)</span><span class="hl-code">,
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</span><span class="hl-quotes">'</span><span class="hl-string">wsw</span><span class="hl-quotes">'</span><span class="hl-code"> => </span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-number">1</span><span class="hl-code">,</span><span class="hl-number">5</span><span class="hl-code">,</span><span class="hl-number">5</span><span class="hl-code">,</span><span class="hl-number">3</span><span class="hl-brackets">)</span><span class="hl-code">,
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</span><span class="hl-quotes">'</span><span class="hl-string">N</span><span class="hl-quotes">'</span><span class="hl-code"> => </span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-number">2</span><span class="hl-code">,</span><span class="hl-number">7</span><span class="hl-code">,</span><span class="hl-number">5</span><span class="hl-code">,</span><span class="hl-number">4</span><span class="hl-code">,</span><span class="hl-number">2</span><span class="hl-brackets">)</span><span class="hl-code">,
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</span><span class="hl-number">15</span><span class="hl-code"> => </span><span class="hl-reserved">array</span><span class="hl-brackets">(</span><span class="hl-number">2</span><span class="hl-code">,</span><span class="hl-number">7</span><span class="hl-code">,</span><span class="hl-number">12</span><span class="hl-brackets">)</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-comment">//</span><span class="hl-comment"> First create a new windrose graph with a title</span><span class="hl-comment"></span><span class="hl-code">
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</span><span class="hl-var">$graph</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">WindroseGraph</span><span class="hl-brackets">(</span><span class="hl-number">400</span><span class="hl-code">,</span><span class="hl-number">400</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-comment">//</span><span class="hl-comment"> Creta an icon to be added to the graph</span><span class="hl-comment"></span><span class="hl-code">
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</span><span class="hl-var">$icon</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">IconPlot</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">tornado.jpg</span><span class="hl-quotes">'</span><span class="hl-code">,</span><span class="hl-number">10</span><span class="hl-code">,</span><span class="hl-number">10</span><span class="hl-code">,</span><span class="hl-number">1</span><span class="hl-number">.3</span><span class="hl-code">,</span><span class="hl-number">50</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$icon</span><span class="hl-code">-></span><span class="hl-identifier">SetAnchor</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">left</span><span class="hl-quotes">'</span><span class="hl-code">,</span><span class="hl-quotes">'</span><span class="hl-string">top</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">Add</span><span class="hl-brackets">(</span><span class="hl-var">$icon</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-comment">//</span><span class="hl-comment"> Setup title</span><span class="hl-comment"></span><span class="hl-code">
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</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">title</span><span class="hl-code">-></span><span class="hl-identifier">Set</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">Windrose icon example</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">title</span><span class="hl-code">-></span><span class="hl-identifier">SetFont</span><span class="hl-brackets">(</span><span class="hl-identifier">FF_VERDANA</span><span class="hl-code">,</span><span class="hl-identifier">FS_BOLD</span><span class="hl-code">,</span><span class="hl-number">12</span><span class="hl-brackets">)</span><span class="hl-code">;
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||
</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">title</span><span class="hl-code">-></span><span class="hl-identifier">SetColor</span><span class="hl-brackets">(</span><span class="hl-quotes">'</span><span class="hl-string">navy</span><span class="hl-quotes">'</span><span class="hl-brackets">)</span><span class="hl-code">;
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||
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||
</span><span class="hl-comment">//</span><span class="hl-comment"> Create the windrose plot.</span><span class="hl-comment"></span><span class="hl-code">
|
||
</span><span class="hl-var">$wp</span><span class="hl-code"> = </span><span class="hl-reserved">new</span><span class="hl-code"> </span><span class="hl-identifier">WindrosePlot</span><span class="hl-brackets">(</span><span class="hl-var">$data</span><span class="hl-brackets">)</span><span class="hl-code">;
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||
|
||
</span><span class="hl-comment">//</span><span class="hl-comment"> Add to graph and send back to client</span><span class="hl-comment"></span><span class="hl-code">
|
||
</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">Add</span><span class="hl-brackets">(</span><span class="hl-var">$wp</span><span class="hl-brackets">)</span><span class="hl-code">;
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||
</span><span class="hl-var">$graph</span><span class="hl-code">-></span><span class="hl-identifier">Stroke</span><span class="hl-brackets">(</span><span class="hl-brackets">)</span><span class="hl-code">;
|
||
</span><span class="hl-inlinetags">?></span></pre></td></tr></table></div></div></div><p><br class="example-break"> </p><div class="figure"><a name="fig.windrose_icon_ex1"></a><p class="title"><b>Figure 21.16. Adding a "tornado" icon to the top left corner <code class="uri"><a class="uri" href="example_src/windrose_icon_ex1.html" target="_top">(<code class="filename">windrose_icon_ex1.php</code>)</a></code> </b></p><div class="figure-contents"> <span class="inlinemediaobject"><img src="images/windrose_icon_ex1.png" alt='Adding a "tornado" icon to the top left corner (windrose_icon_ex1.php)'></span> </div></div><p><br class="figure-break">
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||
</p>
|
||
</div>
|
||
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