<div class="blog">
<h1 id="NAME">
-Quick Game for Toronto Perl Mongers
+The Build Process of SDL Perl
</h1>
<div class="CONTENT">
-<i><br />
-<div style="text-align: right;">Beep ... Boop<br />
-</div></i><br />
+<p>A while ago I had a long chat with mst on why SDL uses Module::Build rather then Make. I told him it is a simple matter of code inertia. The existing Module::Build system has worked well for us so far. Never the less, he convinced me that switching to Make will improve debugging the Build system. But to be able to switch we will need to completely replace the Build system. I am not prepared to do that so I will just present the requirements so mst or someone else can at least attempt to switch.</p><br />
<br />
-So I am preparing a presentation of the new SDL perl for February's Toronto Perl Mongers meeting. What better way to so off SDL perl then with a game? <br />
+<h3>The Build Process </h3><br />
+<b> Alien::SDL </b><br />
<br />
-I started hacking a small point an click game a few days back. I really didn't have a idea in mind, but I did have a goal. I wanted to make a game that shows the basics of a game in SDL. Drawing to screen, game loops, physics and so on. I think I have accomplished it so far. <br />
+<p>SDL Perl depends on a few C libraries for a complete install. This is handled by Alien::SDL. First we look for existing SDL libraries and dependencies by doing a <a href="http://github.com/kthakore/Alien_SDL/blob/master/inc/My/Utility.pm#L581">File::Find</a> for headers. If these headers are found we present and option for the user to use those. We then store these locations in Alien::SDL->config options 'cflags', 'prefix' and 'libs'. If we do not have libraries available even for a minimum SDL installed ( SDL.h is not found). We provide several platform specific options. </p><br />
+<p>For windows we have a simpler process. We download<a href="http://github.com/kthakore/Alien_SDL/blob/master/inc/My/Utility.pm#L7"> prebuilt </a>binaries ( and checksum ) based on the user's selection and just copy them in to the right location. Again the 'prefix', 'cflags', and 'libs' is saved in Alien::SDL->config. </p><br />
+<p>For *nix/MacOSX we download sources and attempt to compile them. To be able to do this we download several other dependencies like libpng, jpeg and pango. You can see how we do this using hashes <a href="http://github.com/kthakore/Alien_SDL/blob/master/inc/My/Utility.pm#L404">here</a>. During the compile process we also apply patches as needed for the <a href="http://github.com/kthakore/Alien_SDL/blob/master/inc/My/Utility.pm#L430">sources</a>. Once this is done we can head to SDL Build.PL </p><br />
+<b> SDL Perl dependency resolution </b><br />
<br />
-Take a look at it <a alt="Click the balls to win" href="http://gist.github.com/301949">here</a>. Download that and call it<a alt="Click the balls to win" href="http://gist.github.com/301949">[Shooter.pl]</a>. To win click the balls.<br />
+SDL's Build is responsible for linking the right libraries to the correct XS. If libraries are missing it will disable the component (not put it in SDL->config). <br />
<br />
-To play this game you need the following:<br />
+<p>For example to build <a href="http://github.com/kthakore/SDL_perl/blob/master/Build.PL#L342">Image.xs</a> we require libsdl, libsdl_image and lib[jpg|png|tiff]. So we would check for these headers in the prefix provided by Alien::SDL->config. If they are not provided we will disable the SDL::Image module. </p><br />
+<p>More over the availability of each library is specified as a -DMACRO to the gcc compiler. This way we can prevent XS failures due to missing libraries using #DEFINES. Here the SDL_image macro is <a href="http://github.com/kthakore/SDL_perl/blob/master/Build.PL#L422">defined</a> and <a href="http://github.com/kthakore/SDL_perl/blob/master/src/Image.xs#L13">used</a>. The availability of the module is then available from <a href="http://github.com/kthakore/SDL_perl/blob/master/t/image.t#L20">SDL::Config->has()</a> <br />
<br />
-<ul><li> <b>Only for Linux)</b> sudo apt-get install libsdl-dev libsdl_gfx-dev </li>
-<li> cpan Alien::SDL </li>
-<li> Click Download Source http://github.com/kthakore/SDL_perl/tree/redesign </li>
-<li> Extract it </li>
-<li> perl Build.PL; perl Build; perl Build install </li>
-<li> perl Shooter.pl </li>
-</ul><br />
-I will put up binaries soon-ish.<br />
<br />
-It is a playable (albeit hard) game right now. All 7 seven levels of it. The purpose of the game is simple click the balls to win. Sounds easy but it isn't. You also get a time in milliseconds after each level. Share your scores on here! I will leave it up to you guys to be honest. <br />
-<br />
-I do have to tidy it up and right documentation for it. This way I will be able to present it clearly to my fellow mongers. I am also still looking for ideas to make this a more polished game. FROGGS recommend I make it a classic NES duck hunt game. I thought since I am using gravity I could do a UFO game out of it where you shoot the UFOs. I am open to your ideas.<div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/3102167581424744259-1585061047069454098?l=yapgh.blogspot.com' alt='' /></div>
-<p><a href="http://feedads.g.doubleclick.net/~a/xSNM-fJPtTMLn88P3vJeOy3aoV4/0/da"><img src="http://feedads.g.doubleclick.net/~a/xSNM-fJPtTMLn88P3vJeOy3aoV4/0/di" border="0" ismap="true"></img></a><br/>
-<a href="http://feedads.g.doubleclick.net/~a/xSNM-fJPtTMLn88P3vJeOy3aoV4/1/da"><img src="http://feedads.g.doubleclick.net/~a/xSNM-fJPtTMLn88P3vJeOy3aoV4/1/di" border="0" ismap="true"></img></a></p><img src="http://feeds.feedburner.com/~r/YetAnotherPerlGameHackeryapgh/~4/oR6t0trX8yM" height="1" width="1"/></div></div>
\ No newline at end of file
+<b> Conclusion </b> <br />
+<p>This is a high level overview of our Build process, because frankly I hate traumatizing my brain with this again. Credits have to go to FROGGS and kmx for helping with this Build scheme. Hopefully my post have helped people at the very least appreciate the problem scope of this Build system. That said I believe a fresh written build system, with these requirements in mind, will be more then welcome.<br />
+</p><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/3102167581424744259-4514794130108689562?l=yapgh.blogspot.com' alt='' /></div>
+<p><a href="http://feedads.g.doubleclick.net/~a/SHI8waMCUMOT4LmhUSkV3-Y1cK8/0/da"><img src="http://feedads.g.doubleclick.net/~a/SHI8waMCUMOT4LmhUSkV3-Y1cK8/0/di" border="0" ismap="true"></img></a><br/>
+<a href="http://feedads.g.doubleclick.net/~a/SHI8waMCUMOT4LmhUSkV3-Y1cK8/1/da"><img src="http://feedads.g.doubleclick.net/~a/SHI8waMCUMOT4LmhUSkV3-Y1cK8/1/di" border="0" ismap="true"></img></a></p><img src="http://feeds.feedburner.com/~r/YetAnotherPerlGameHackeryapgh/~4/fTwVmM222rA" height="1" width="1"/></div></div>
\ No newline at end of file
projects / sdlgit/SDL-Site.git / blobdiff