Updated

[sdlgit/SDL-Site.git] / pages / blog-0009.html-inc

diff --git a/pages/blog-0009.html-inc b/pages/blog-0009.html-inc
index 0de3c83..2e202e7 100644 (file)
--- a/pages/blog-0009.html-inc
+++ b/pages/blog-0009.html-inc
@@ -1,59 +1,81 @@
 <div class="blog">
 <h1 id="NAME">
-Once in a while .... (set_event_filter)
+Providing direct memory access to SDL_Surface's pixels
 </h1>
 <div class="CONTENT">
-<div style="text-align: right;"><i> <br />
-Once in a while <br />
-Things just work! <br />
-</i><br />
-</div><br />
+<p>In an attempt to make pixel access easier on SDL_Surface pixels. I have started work on <a href="http://github.com/kthakore/SDL_perl/commit/7ee1a1a7f162080a6fa5274e95b80961486e21e5">SDLx::Surface</a>. So far I have only start on the 32 bpp surfaces.</p><br />
+<p>The general idea is to make Pointer Values (PV) of each pixel in the surface and place them into a 2D matrix. First I make pointer values like this: </p><br />
+<pre style='color:#d1d1d1;background:#000000;'>SV <span style='color:#d2cd86; '>*</span> get_pixel32 <span style='color:#d2cd86; '>(</span>SDL_Surface <span style='color:#d2cd86; '>*</span>surface<span style='color:#d2cd86; '>,</span> <span style='color:#e66170; font-weight:bold; '>int</span> x<span style='color:#d2cd86; '>,</span> <span style='color:#e66170; font-weight:bold; '>int</span> y<span style='color:#d2cd86; '>)</span>
+<span style='color:#b060b0; '>{</span>
+ <span style='color:#9999a9; '>//Convert the pixels to 32 bit </span>
+ Uint32 <span style='color:#d2cd86; '>*</span>pixels <span style='color:#d2cd86; '>=</span> <span style='color:#d2cd86; '>(</span>Uint32 <span style='color:#d2cd86; '>*</span><span style='color:#d2cd86; '>)</span>surface<span style='color:#d2cd86; '>-</span><span style='color:#d2cd86; '>></span>pixels<span style='color:#b060b0; '>;</span> 
+
+ <span style='color:#9999a9; '>//Get the requested pixel  </span>
+ Uint32<span style='color:#d2cd86; '>*</span> u_ptr <span style='color:#d2cd86; '>=</span>  pixels <span style='color:#d2cd86; '>+</span> <span style='color:#d2cd86; '>(</span> y <span style='color:#d2cd86; '>*</span> surface<span style='color:#d2cd86; '>-</span><span style='color:#d2cd86; '>></span>w <span style='color:#d2cd86; '>)</span> <span style='color:#d2cd86; '>+</span> x <span style='color:#b060b0; '>;</span> 
+
+        SV<span style='color:#d2cd86; '>*</span> sv <span style='color:#d2cd86; '>=</span> newSVpv<span style='color:#d2cd86; '>(</span><span style='color:#02d045; '>"</span><span style='color:#00c4c4; '>a</span><span style='color:#02d045; '>"</span><span style='color:#d2cd86; '>,</span><span style='color:#008c00; '>1</span><span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>//Make a temp SV* value on the go</span>
+        SvCUR_set<span style='color:#d2cd86; '>(</span>sv<span style='color:#d2cd86; '>,</span> <span style='color:#e66170; font-weight:bold; '>sizeof</span><span style='color:#d2cd86; '>(</span>Uint32<span style='color:#d2cd86; '>)</span><span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>//Specify the new CUR length</span>
+ SvLEN_set<span style='color:#d2cd86; '>(</span>sv<span style='color:#d2cd86; '>,</span> <span style='color:#e66170; font-weight:bold; '>sizeof</span><span style='color:#d2cd86; '>(</span>Uint32<span style='color:#d2cd86; '>)</span><span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>//Specify the LEN length</span>
+        SvPV_set<span style='color:#d2cd86; '>(</span>sv<span style='color:#d2cd86; '>,</span><span style='color:#d2cd86; '>(</span><span style='color:#e66170; font-weight:bold; '>char</span><span style='color:#d2cd86; '>*</span><span style='color:#d2cd86; '>)</span>u_ptr<span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>// set the actual pixel's pointer as the memory space to use</span>
+
+ <span style='color:#e66170; font-weight:bold; '>return</span> sv<span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>//make a modifiable reference using u_ptr's place as the memory :)</span>
+
+<span style='color:#b060b0; '>}</span>
+</pre><br />
+<p>Next I loop through all the pixels and put them in a 2D array format, shown below: </p><pre style='color:#d1d1d1;background:#000000;'>AV <span style='color:#d2cd86; '>*</span> construct_p_matrix <span style='color:#d2cd86; '>(</span> SDL_Surface <span style='color:#d2cd86; '>*</span>surface <span style='color:#d2cd86; '>)</span>
+<span style='color:#b060b0; '>{</span>
+    AV <span style='color:#d2cd86; '>*</span> matrix <span style='color:#d2cd86; '>=</span> newAV<span style='color:#d2cd86; '>(</span><span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span>
+     <span style='color:#e66170; font-weight:bold; '>int</span> i<span style='color:#d2cd86; '>,</span> j<span style='color:#b060b0; '>;</span>
+     <span style='color:#e66170; font-weight:bold; '>for</span><span style='color:#d2cd86; '>(</span>  i <span style='color:#d2cd86; '>=</span><span style='color:#008c00; '>0</span> <span style='color:#b060b0; '>;</span> i <span style='color:#d2cd86; '>&lt;</span> surface<span style='color:#d2cd86; '>-</span><span style='color:#d2cd86; '>></span>w<span style='color:#b060b0; '>;</span> i<span style='color:#d2cd86; '>+</span><span style='color:#d2cd86; '>+</span><span style='color:#d2cd86; '>)</span>
+      <span style='color:#b060b0; '>{</span>
+        AV <span style='color:#d2cd86; '>*</span> matrix_row <span style='color:#d2cd86; '>=</span> newAV<span style='color:#d2cd86; '>(</span><span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span>
+        <span style='color:#e66170; font-weight:bold; '>for</span><span style='color:#d2cd86; '>(</span> j <span style='color:#d2cd86; '>=</span><span style='color:#008c00; '>0</span> <span style='color:#b060b0; '>;</span> j <span style='color:#d2cd86; '>&lt;</span> surface<span style='color:#d2cd86; '>-</span><span style='color:#d2cd86; '>></span>h<span style='color:#b060b0; '>;</span> j<span style='color:#d2cd86; '>+</span><span style='color:#d2cd86; '>+</span><span style='color:#d2cd86; '>)</span>
+        <span style='color:#b060b0; '>{</span>
+           av_push<span style='color:#d2cd86; '>(</span>matrix_row<span style='color:#d2cd86; '>,</span> get_pixel32<span style='color:#d2cd86; '>(</span>surface<span style='color:#d2cd86; '>,</span> i<span style='color:#d2cd86; '>,</span>j<span style='color:#d2cd86; '>)</span> <span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span>
+        <span style='color:#b060b0; '>}</span>
+        av_push<span style='color:#d2cd86; '>(</span>matrix<span style='color:#d2cd86; '>,</span> newRV_noinc<span style='color:#d2cd86; '>(</span><span style='color:#d2cd86; '>(</span>SV<span style='color:#d2cd86; '>*</span><span style='color:#d2cd86; '>)</span> matrix_row<span style='color:#d2cd86; '>)</span> <span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span>
+      <span style='color:#b060b0; '>}</span>
+
+ <span style='color:#e66170; font-weight:bold; '>return</span> matrix<span style='color:#b060b0; '>;</span>
+<span style='color:#b060b0; '>}</span>
+</pre><br />
+<p>You can see the complete <a href="http://github.com/kthakore/SDL_perl/blob/7ee1a1a7f162080a6fa5274e95b80961486e21e5/src/SDLx/Surface.xs">here</a>.</p><br />
+<p>In Perl I can do a get access on this pixel using: </p><br />
 <br />
-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 />
-<br />
-<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>
-<p><a href="http://feedads.g.doubleclick.net/~a/e5FjkjzCKI5FggkvV6c3mlOMCG4/0/da"><img src="http://feedads.g.doubleclick.net/~a/e5FjkjzCKI5FggkvV6c3mlOMCG4/0/di" border="0" ismap="true"></img></a><br/>
-<a href="http://feedads.g.doubleclick.net/~a/e5FjkjzCKI5FggkvV6c3mlOMCG4/1/da"><img src="http://feedads.g.doubleclick.net/~a/e5FjkjzCKI5FggkvV6c3mlOMCG4/1/di" border="0" ismap="true"></img></a></p><img src="http://feeds.feedburner.com/~r/YetAnotherPerlGameHackeryapgh/~4/nw1gIYSWG5M" height="1" width="1"/></div></div>
\ No newline at end of file
+<pre style='color:#d1d1d1;background:#000000;'><span style='color:#e66170; font-weight:bold; '>my</span> $surf32_matrix <span style='color:#d2cd86; '>=</span> <span style='color:#904050; '>SDLx</span><span style='color:#d2cd86; '>::</span><span style='color:#904050; '>Surface</span><span style='color:#d2cd86; '>:</span><span style='color:#d2cd86; '>:</span>pixel_array<span style='color:#d2cd86; '>(</span>$screen_surface<span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span>
+   <span style='color:#e66170; font-weight:bold; '>print</span> <span style='color:#e66170; font-weight:bold; '>unpack</span> <span style='color:#00c4c4; '>'b*'</span><span style='color:#d2cd86; '>,</span> $surf32_matrix<span style='color:#d2cd86; '>-></span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span><span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '># pixel value at x = 0 and y =0</span>
+<span style='color:#9999a9; '>#OUTPUT:</span>
+<span style='color:#9999a9; '># 11111111000000000000000000000000</span>
+</pre><br />
+<p>The structure of the PV is using Devel::Peek is : </p><br />
+<pre style='color:#d1d1d1;background:#000000;'><span style='color:#e66170; font-weight:bold; '>print</span> Dump $surf32_matrix<span style='color:#d2cd86; '>-></span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span><span style='color:#b060b0; '>;</span>
+<span style='color:#9999a9; '>#OUTPUT:</span>
+<span style='color:#9999a9; '>#SV = PV(0xed0dbc) at 0xeb5344</span>
+<span style='color:#9999a9; '>#  REFCNT = 1</span>
+<span style='color:#9999a9; '>#  FLAGS = (POK,pPOK)</span>
+<span style='color:#9999a9; '>#  PV = 0x9e04ac "\0\0\377\0"</span>
+<span style='color:#9999a9; '>#  CUR = 4</span>
+<span style='color:#9999a9; '>#  LEN = 4</span>
+</pre><br />
+<p>The problem is in setting the value of this pointer value. I have tried the following things with no success:</p><br />
+<pre style='color:#d1d1d1;background:#000000;'><span style='color:#e66170; font-weight:bold; '>if</span> <span style='color:#d2cd86; '>(</span> <span style='color:#904050; '>SDL</span><span style='color:#d2cd86; '>::</span><span style='color:#904050; '>Video</span><span style='color:#d2cd86; '>:</span><span style='color:#d2cd86; '>:</span>MUSTLOCK<span style='color:#d2cd86; '>(</span>$screen_surface<span style='color:#d2cd86; '>)</span> <span style='color:#d2cd86; '>)</span> <span style='color:#b060b0; '>{</span>
+    <span style='color:#e66170; font-weight:bold; '>return</span> <span style='color:#e66170; font-weight:bold; '>if</span> <span style='color:#d2cd86; '>(</span> <span style='color:#904050; '>SDL</span><span style='color:#d2cd86; '>::</span><span style='color:#904050; '>Video</span><span style='color:#d2cd86; '>:</span><span style='color:#d2cd86; '>:</span>lock_surface<span style='color:#d2cd86; '>(</span>$screen_surface<span style='color:#d2cd86; '>)</span> <span style='color:#d2cd86; '>&lt;</span> <span style='color:#00a800; '>0</span> <span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>#required for pixel operations</span>
+<span style='color:#b060b0; '>}</span>
+
+<span style='color:#9999a9; '>#USING pack</span>
+
+<span style='color:#e66170; font-weight:bold; '>my</span> $green <span style='color:#d2cd86; '>=</span> <span style='color:#e66170; font-weight:bold; '>pack</span> <span style='color:#00c4c4; '>'b*'</span><span style='color:#d2cd86; '>,</span> <span style='color:#00c4c4; '>'11111111000000000000000000000000'</span><span style='color:#b060b0; '>;</span>
+<span style='color:#e66170; font-weight:bold; '>substr</span><span style='color:#d2cd86; '>(</span> $surf32_matrix<span style='color:#d2cd86; '>-></span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span><span style='color:#d2cd86; '>,</span> <span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>,</span> <span style='color:#00a800; '>8</span> <span style='color:#d2cd86; '>*</span> <span style='color:#00a800; '>4</span><span style='color:#d2cd86; '>,</span> $green<span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>#no change</span>
+<span style='color:#9999a9; '>#substr( $surf32_matrix->[0][0], 0, 8 * 4, 0xFF000000); segfault</span>
+<span style='color:#e66170; font-weight:bold; '>substr</span><span style='color:#d2cd86; '>(</span> ${$surf32_matrix<span style='color:#d2cd86; '>-></span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span>}<span style='color:#d2cd86; '>,</span> <span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>,</span> <span style='color:#00a800; '>8</span> <span style='color:#d2cd86; '>*</span> <span style='color:#00a800; '>4</span><span style='color:#d2cd86; '>,</span> <span style='color:#00a800; '>0xFF000000</span><span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>#no change</span>
+<span style='color:#9999a9; '>#$surf32_matrix->[0][0] = $green; SEGFAULT's cannot write to memory</span>
+${$surf32_matrix<span style='color:#d2cd86; '>-></span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span><span style='color:#d2cd86; '>[</span><span style='color:#00a800; '>0</span><span style='color:#d2cd86; '>]</span>} <span style='color:#d2cd86; '>=</span> $green<span style='color:#b060b0; '>;</span> <span style='color:#9999a9; '>#no change</span>
+
+
+<span style='color:#904050; '>SDL</span><span style='color:#d2cd86; '>::</span><span style='color:#904050; '>Video</span><span style='color:#d2cd86; '>:</span><span style='color:#d2cd86; '>:</span>unlock_surface<span style='color:#d2cd86; '>(</span>$screen_surface<span style='color:#d2cd86; '>)</span>
+  <span style='color:#e66170; font-weight:bold; '>if</span> <span style='color:#d2cd86; '>(</span> <span style='color:#904050; '>SDL</span><span style='color:#d2cd86; '>::</span><span style='color:#904050; '>Video</span><span style='color:#d2cd86; '>:</span><span style='color:#d2cd86; '>:</span>MUSTLOCK<span style='color:#d2cd86; '>(</span>$screen_surface<span style='color:#d2cd86; '>)</span> <span style='color:#d2cd86; '>)</span><span style='color:#b060b0; '>;</span>
+</pre><br />
+<p>You can see an example <a href="http://paste.scsys.co.uk/45111">here</a>.</p><br />
+<p>Any help will be greatly appreciated. </p><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/3102167581424744259-1929043568015240773?l=yapgh.blogspot.com' alt='' /></div>
+<p><a href="http://feedads.g.doubleclick.net/~a/1Rx7lBLzyC2ksXyZwl9Q_nlI6iE/0/da"><img src="http://feedads.g.doubleclick.net/~a/1Rx7lBLzyC2ksXyZwl9Q_nlI6iE/0/di" border="0" ismap="true"></img></a><br/>
+<a href="http://feedads.g.doubleclick.net/~a/1Rx7lBLzyC2ksXyZwl9Q_nlI6iE/1/da"><img src="http://feedads.g.doubleclick.net/~a/1Rx7lBLzyC2ksXyZwl9Q_nlI6iE/1/di" border="0" ismap="true"></img></a></p><img src="http://feeds.feedburner.com/~r/YetAnotherPerlGameHackeryapgh/~4/q5F5dgfg5Fg" height="1" width="1"/></div></div>
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