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Once in a while .... (set_event_filter)
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<div style="text-align: right;"><i> <br />
Once in a while <br />
Things just work! <br />
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So I have been hacking for a while on SDL::Events::set_event_filter. The code below is an example usage. The magic behind this is <a href="http://github.com/kthakore/SDL_perl/blob/1712fe42d62c2a3e382e6bf91366eb2ce9d2f5f4/src/Core/Events.xs">here</a> <br />
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<pre><a href="" name="line1"> 1</a> <span style="color: #444444;">#!/usr/bin/perl -w
<a href="" name="line2"> 2</a> </span><b>use</b> strict;
<a href="" name="line3"> 3</a> <b>use</b> warnings;
<a href="" name="line4"> 4</a> <b>use</b> SDL v2.3; <span style="color: #444444;">#Require the redesign branch
<a href="" name="line5"> 5</a> </span><b>use</b> SDL::Video;
<a href="" name="line6"> 6</a> <b>use</b> SDL::Event;
<a href="" name="line7"> 7</a> <b>use</b> SDL::Events;
<a href="" name="line8"> 8</a> 
<a href="" name="line9"> 9</a> SDL::init<span style="color: #4444ff;"><b>(</b></span>SDL_INIT_VIDEO<span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line10">10</a> <b>my</b> <span style="color: #2040a0;">$display</span> = SDL::Video::set_video_mode<span style="color: #4444ff;"><b>(</b></span>640,480,32, SDL_SWSURFACE <span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line11">11</a> <b>my</b>  <span style="color: #2040a0;">$event</span> = SDL::Event-&gt;<b>new</b><span style="color: #4444ff;"><b>(</b></span><span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line12">12</a> 
<a href="" name="line13">13</a> <span style="color: #444444;">#This filters out all ActiveEvents
<a href="" name="line14">14</a> </span><b>my</b> <span style="color: #2040a0;">$filter</span> = sub <span style="color: #4444ff;"><b>{</b></span> 
<a href="" name="line15">15</a>      <b>my</b> <span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$e</span>, <span style="color: #2040a0;">$type</span><span style="color: #4444ff;"><b>)</b></span> = <span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$_</span><span style="color: #4444ff;"><b>[</b></span>0<span style="color: #4444ff;"><b>]</b></span>, <span style="color: #2040a0;">$_</span><span style="color: #4444ff;"><b>[</b></span>0<span style="color: #4444ff;"><b>]</b></span>-&gt;type<span style="color: #4444ff;"><b>)</b></span>; 
<a href="" name="line16">16</a>      <b>if</b><span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$type</span> == SDL_ACTIVEEVENT<span style="color: #4444ff;"><b>)</b></span><span style="color: #4444ff;"><b>{</b></span> <b>return</b> 0 <span style="color: #4444ff;"><b>}</b></span> 
<a href="" name="line17">17</a>      <b>elsif</b><span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$type</span> == SDL_MOUSEBUTTONDOWN &amp;&amp; <span style="color: #2040a0;">$e</span>-&gt;button_button == 1<span style="color: #4444ff;"><b>)</b></span><span style="color: #4444ff;"><b>{</b></span> <b>return</b> 0 <span style="color: #4444ff;"><b>}</b></span>
<a href="" name="line18">18</a>      <b>else</b> <span style="color: #4444ff;"><b>{</b></span> <b>return</b> 1; <span style="color: #4444ff;"><b>}</b></span>
<a href="" name="line19">19</a>       <span style="color: #4444ff;"><b>}</b></span>;
<a href="" name="line20">20</a> 
<a href="" name="line21">21</a> SDL::Events::set_event_filter<span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$filter</span><span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line22">22</a> 
<a href="" name="line23">23</a> <b>while</b><span style="color: #4444ff;"><b>(</b></span>1<span style="color: #4444ff;"><b>)</b></span>
<a href="" name="line24">24</a> <span style="color: #4444ff;"><b>{</b></span>
<a href="" name="line25">25</a> 
<a href="" name="line26">26</a>   SDL::Events::pump_events<span style="color: #4444ff;"><b>(</b></span><span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line27">27</a>   <b>if</b><span style="color: #4444ff;"><b>(</b></span>SDL::Events::poll_event<span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$event</span><span style="color: #4444ff;"><b>)</b></span><span style="color: #4444ff;"><b>)</b></span>
<a href="" name="line28">28</a>   <span style="color: #4444ff;"><b>{</b></span>
<a href="" name="line29">29</a> 
<a href="" name="line30">30</a>   <b>if</b><span style="color: #4444ff;"><b>(</b></span>  <span style="color: #2040a0;">$event</span>-&gt;type == SDL_ACTIVEEVENT<span style="color: #4444ff;"><b>)</b></span>
<a href="" name="line31">31</a>  <span style="color: #4444ff;"><b>{</b></span>
<a href="" name="line32">32</a>  <span style="color: brown;"><b>print</b></span> <span style="color: green;">"Hello Mouse!!!<span style="color: #77dd77;">\n</span>"</span> <b>if</b> <span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$event</span>-&gt;active_gain &amp;&amp; <span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$event</span>-&gt;active_state == SDL_APPMOUSEFOCUS<span style="color: #4444ff;"><b>)</b></span> <span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line33">33</a>  <span style="color: brown;"><b>print</b></span> <span style="color: green;">"Bye Mouse!!!<span style="color: #77dd77;">\n</span>"</span> <b>if</b> <span style="color: #4444ff;"><b>(</b></span>!<span style="color: #2040a0;">$event</span>-&gt;active_gain &amp;&amp; <span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$event</span>-&gt;active_state == SDL_APPMOUSEFOCUS<span style="color: #4444ff;"><b>)</b></span> <span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line34">34</a>         <span style="color: #4444ff;"><b>}</b></span>
<a href="" name="line35">35</a>   <b>if</b><span style="color: #4444ff;"><b>(</b></span> <span style="color: #2040a0;">$event</span>-&gt;type == SDL_MOUSEBUTTONDOWN<span style="color: #4444ff;"><b>)</b></span>
<a href="" name="line36">36</a>    <span style="color: #4444ff;"><b>{</b></span>
<a href="" name="line37">37</a>  <b>my</b> <span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$x</span>, <span style="color: #2040a0;">$y</span>, <span style="color: #2040a0;">$but</span> <span style="color: #4444ff;"><b>)</b></span> = <span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$event</span>-&gt;button_x, <span style="color: #2040a0;">$event</span>-&gt;button_y, <span style="color: #2040a0;">$event</span>-&gt;button_button<span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line38">38</a>  <span style="color: brown;"><b>warn</b></span> <span style="color: green;">"<span style="color: #2040a0;">$but</span> CLICK!!! at <span style="color: #2040a0;">$x</span> and <span style="color: #2040a0;">$y</span> <span style="color: #77dd77;">\n</span>"</span>;
<a href="" name="line39">39</a>  <span style="color: #4444ff;"><b>}</b></span>
<a href="" name="line40">40</a> 
<a href="" name="line41">41</a>       <b>last</b> <b>if</b><span style="color: #4444ff;"><b>(</b></span><span style="color: #2040a0;">$event</span>-&gt;type == SDL_QUIT<span style="color: #4444ff;"><b>)</b></span>;
<a href="" name="line42">42</a>   <span style="color: #4444ff;"><b>}</b></span>
<a href="" name="line43">43</a> <span style="color: #4444ff;"><b>}</b></span>
<a href="" name="line44">44</a> SDL::quit<span style="color: #4444ff;"><b>(</b></span><span style="color: #4444ff;"><b>)</b></span>;&nbsp;</pre><pre>&nbsp;</pre><pre>&nbsp;</pre><pre>Tinker with $filter and look at perldoc lib/SDL/pods/Event.pod.&nbsp;</pre><pre>&nbsp;</pre><pre>Have fun,</pre><pre>--yapgh</pre><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/3102167581424744259-2301663122914111362?l=yapgh.blogspot.com' alt='' /></div>
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